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1. "Ag8SnTe6" — Ein neuer stabiler Vertreter der Argyrodite ? "Ag8SnTe6" -a New Stable Argyrodite ?

Author:
Bernd Gather; Roger Blachnik
Source:
Zeitschrift für Naturforschung 2014 v.38 no.6 pp. 786-787
ISSN:
0932-0776
Subject:
X-radiation; chemical compounds; chemical reactions; chemical structure
Abstract:
... DTA, X-ray and microprobe measurements show, that the compound "Ag₈SnTe₆" seems not to be a stable argyrodite. ...
DOI:
10.1515/znb-1983-0622

2. (+)- and (−)-Cajanusine, a Pair of New Enantiomeric Stilbene Dimers with a New Skeleton from the Leaves of Cajanus cajan

Author:
Li Xiao-Long; Zhao Bing-Xin; Huang Xiao-Jun; Zhang Dong-Mei; Jiang Ren-Wang; Li Ying-Jie; Jian Yu-Qing; Wang Ying; Li Yao-Lan; Ye Wen-Cai
Source:
Organic letters 2014 v.16 no.1 pp. 224-227
ISSN:
1523-7052
Subject:
Cajanus cajan; X-ray diffraction; chemical reactions; chemical structure; hepatoma; humans; leaves; neoplasm cells; organic compounds; spectroscopy
Abstract:
... A pair of new enantiomeric stilbene dimers, (+)- and (−)-cajanusine [(+)-1 and (−)-1], with a unique coupling pattern were isolated from the leaves of Cajanus cajan. Their structures including absolute configurations were elucidated on the basis of comprehensive spectroscopic and single-crystal X-ray diffraction analyses, as well as CD calculations. The plausible biogenetic pathway of 1 was also p ...
DOI:
10.1021/ol403211a

3. (+)- and (−)-Pestaloxazine A, a Pair of Antiviral Enantiomeric Alkaloid Dimers with a Symmetric Spiro[oxazinane-piperazinedione] Skeleton from Pestalotiopsis sp.

Author:
Jia Yan-Lai; Wei Mei-Yan; Chen Hai-Yan; Guan Fei-Fei; Wang Chang-Yun; Shao Chang-Lun
Source:
Organic letters 2015 v.17 no.17 pp. 4216-4219
ISSN:
1523-7052
Subject:
Pestalotiopsis; X-ray diffraction; alkaloids; antiviral properties; chemical reactions; chemical structure; corals; fungi; high performance liquid chromatography; inhibitory concentration 50; spectroscopy
Abstract:
... A pair of new enantiomeric alkaloid dimers, (+)- and (−)-pestaloxazine A (1), with an unprecedented symmetric spiro[oxazinane-piperazinedione] skeleton, consisting of 22 carbons and 12 heteroatoms, were isolated from a Pestalotiopsis sp. fungus derived from a soft coral. Separation of the enantiomeric alkaloid dimers was achieved by chiral HPLC. Their structures including absolute configurations w ...
DOI:
10.1021/acs.orglett.5b01995

4. (+)- and (−)-Petromyroxols: Antipodal Tetrahydrofurandiols from Larval Sea Lamprey (Petromyzon marinus L.) That Elicit Enantioselective Olfactory Responses

Author:
Li Ke; Huertas Mar; Brant Cory; Chung-Davidson Yu-Wen; Bussy Ugo; Hoye Thomas R.; Li Weiming
Source:
Organic letters 2015 v.17 no.2 pp. 286-289
ISSN:
1523-7052
Subject:
Petromyzon marinus; chemical reactions; chromatography; enantiomers; enantioselectivity; fatty acids; larvae; synthetic products; tetrahydrofuran
Abstract:
... (+)- and (−)-Petromyroxol [(+)-1 and (−)-1, respectively], two novel tetrahydrofuran (THF)-diol fatty acid enantiomers, were isolated from water conditioned with larval sea lamprey. We herein describe their isolation and subsequent resolution using chiral chromatography. The absolute configuration of each enantiomer was determined by a combination of Mosher ester analysis and comparison with relat ...
DOI:
10.1021/ol5033893

5. (+)- and (−)-Preuisolactone A: A Pair of Caged Norsesquiterpenoidal Enantiomers with a Tricyclo[4.4.0¹,⁶.0²,⁸]decane Carbon Skeleton from the Endophytic Fungus Preussia isomera

Author:
Lu-Lin Xu; Hai-Li Chen; Ping Hai; Yuan Gao; Chuan-Dong Xie; Xiao-Long Yang; Ikuro Abe
Source:
Organic letters 2019 v.21 no.4 pp. 1078-1081
ISSN:
1523-7052
Subject:
Micrococcus luteus; Preussia; X-ray diffraction; antibacterial properties; biochemical pathways; carbon; chemical reactions; decane; enantiomers; endophytes; fungi; spectroscopy
Abstract:
... A pair of enantiomeric norsesquiterpenoids, (+)- and (−)-preuisolactone A (1) [(+)-1 and (−)-1)] featuring an unprecedented tricyclo[4.4.0¹,⁶.0²,⁸]decane carbon scaffold were isolated from Preussia isomera. Their structures were determined by spectroscopic and computed methods and X-ray crystallography. Compounds (+)-1 and (−)-1 are two rare naturally occurring sesquiterpenoidal enantiomers. A pla ...
DOI:
10.1021/acs.orglett.8b04123

6. (+)- and (−)-Spiroreticulatine, A Pair of Unusual Spiro Bisheterocyclic Quinoline-imidazole Alkaloids from the South China Sea Sponge Fascaplysinopsis reticulata

Author:
Wang Qi; Tang Xuli; Luo Xiangchao; de Voogd Nicole J.; Li Pinglin; Li Guoqiang
Source:
Organic letters 2015 v.17 no.14 pp. 3458-3461
ISSN:
1523-7052
Subject:
X-ray diffraction; alkaloids; chemical reactions; chemical structure; interleukin-2; neoplasm cells; spectral analysis; tryptophan; South China Sea
Abstract:
... A pair of novel bisheterocyclic quinoline-imidazole alkaloids, (+)- and (−)-spiroreticulatine (1), were isolated from the South China Sea sponge Fascaplysinopsis reticulata. The structures and absolute configurations were elucidated by comprehensive spectroscopic analysis, single-crystal X-ray diffraction, and quantum chemical calculation methods. Spiroreticulatine is the first example of a sponge ...
DOI:
10.1021/acs.orglett.5b01503

7. (+)-Abscisic acid 8'-hydroxylase is a cytochrome P450 monooxygenase

Author:
Krochko, J.E.; Abrams, G.D.; Loewen, M.K.; Abrams, S.R.; Cutler, A.J.
Source:
Plant physiology 1998 v.118 no.3 pp. 849-860
ISSN:
0032-0889
Subject:
Zea mays; cell suspension culture; cell membranes; protein composition; cytochrome P-450; oxygenases; abscisic acid; metabolism; enzyme activity; light; oxygen; cytochrome c; carbon monoxide; dose response; chemical reactions; biochemical pathways; NADP (coenzyme)
Abstract:
... Abscisic acid (ABA) 8'-hydroxylase catalyzes the first step in the oxidative degradation of (+)-ABA. The development of a robust in vitro assay has now permitted detailed examination and characterization of this enzyme. Although several factors (buffer, cofactor, and source tissue) were critical in developing the assay, the most important of these was the identification of a tissue displaying high ...

8. (+)-Camphor Derivative Induced Asymmetric [2 + 2] Photoaddition Reaction

Author:
Zhao Guolei; Yang Chao; Sun Hongnan; Lin Run; Xia Wujiong
Source:
Organic letters 2012 v.14 no.3 pp. 776-779
ISSN:
1523-7052
Subject:
chemical reactions; chemical structure; diastereoselectivity; organic compounds
Abstract:
... An efficient approach to construct an enantiomerically pure cyclobutane skeleton by means of the chiral auxiliary induced [2 + 2] photoaddition reactions has been described. This asymmetric photoreaction exhibited high diastereoselectivity and provided the photoadducts in excellent yields. ...
DOI:
10.1021/ol203314y

9. (+)-Catechin-aldehyde condensations: competition between acetaldehyde and glyoxylic acid

Author:
Drinkine, J.; Glories, Y.; Saucier, C.
Source:
Journal of agricultural and food chemistry 2005 v.53 no.19 pp. 7552-7558
ISSN:
0021-8561
Subject:
acetaldehyde; glyoxylic acid; chemical reactions; catechin; model food systems; wines; winemaking; food chemistry
Abstract:
... (+)-Catechin reaction with two aldehydes (acetaldehyde and glyoxylic acid) was studied in winelike model solution. The two aldehydes were reacted either individually or together with (+)-catechin and in molar excess. The reactions were followed by HLPC-UV and HPLC-ESI/MS to monitor (+)-catechin disappearance as well as dimer and polymer appearance. In all reactions a reaction order of close to 1 f ...
DOI:
10.1021/jf0504723

10. (+)-Episesaminone, a Sesamum indicum furofuran lignan. Isolation and hemisynthesis

Author:
Marchand, P.A.; Kato, M.J.; Lewis, N.G.
Source:
Journal of natural products 1997 v.60 no.11 pp. 1189-1192
ISSN:
0163-3864
Subject:
Sesamum indicum; seeds; furans; lignans; spectral analysis; chemical structure; biosynthesis; biochemical pathways; chemical reactions; chemical constituents of plants
DOI:
10.1021/np9702953

11. (+)-Neplanocin F, 2′-fluoroneplanocin, and a 6′-isoneplanocin via a common versatile cyclopentenol precursor

Author:
Chong Liu; Qi Chen; Stewart W. Schneller
Source:
Tetrahedron letters 2011 v.52 no.38 pp. 4931-4933
ISSN:
0040-4039
Subject:
chemical reactions; chemical structure; hydrides; nucleosides; organic compounds
Abstract:
... Reductive (diisobutylaluminum hydride) ring opening of an acetal protected cyclopentenol has provided a precursor adaptable to uniquely substituted carbocyclic nucleosides. To illustrate the broad implication of this process the preparation of unnatural (+)-neplanocin F, an ara-like 2′-fluoroneplanocin, and a 6′- isomeric l-like neplanocin analog is described. ...
DOI:
10.1016/j.tetlet.2011.07.059

12. (+/−)-Lucidumone, a COX-2 Inhibitory Caged Fungal Meroterpenoid from Ganoderma lucidum

Author:
Yong-Ming Yan; Hao-Xing Zhang; Huan Liu; Yan Wang; Jing-Bo Wu; Yan-Peng Li; Yong-Xian Cheng
Source:
Organic letters 2019 v.21 no.21 pp. 8523-8527
ISSN:
1523-7052
Subject:
Ganoderma lucidum; X-ray diffraction; amino acids; biochemical pathways; chemical reactions; chemical structure; meroterpenoids
Abstract:
... (±)-Lucidumone (1), an enantiomeric meroterpenoid possessing an unprecedented skeleton comprising a fused 6/5/6/6/5 polycyclic system, was isolated from Ganoderma lucidum and structurally identified. The absolute configuration of (−)-1 was assigned by single-crystal X-ray crystallography. A plausible biosynthetic pathway for 1 is proposed. A chemical biology approach reveals that (−)-1 selectively ...
DOI:
10.1021/acs.orglett.9b02840

13. (1,2-Diaminoethane-1,2-diyl)bis(N-methylpyridinium) Salts as a Prospective Platform for Designing Recyclable Prolinamide-Based Organocatalysts

Author:
Lisnyak Vladislav G.; Kucherenko Alexander S.; Valeev Edward F.; Zlotin Sergei G.
Source:
Journal of organic chemistry 2015 v.80 no.19 pp. 9570-9577
ISSN:
1520-6904
Subject:
catalysts; chemical reactions; chemical structure; organic chemistry; organic compounds; salts
Abstract:
... A new efficient and highly recyclable organocatalyst has been developed for asymmetric cross-aldol reactions under neat conditions in ketone–ketone, ketone–aldehyde, and aldehyde–aldehyde systems. The catalyst features two prolinamide fragments and a C₂-symmetrical (1,2-diaminoethane-1,2-diyl)bis(N-methylpyridinium) group. The catalyst retained high activity and excellent stereoselection over the ...
DOI:
10.1021/acs.joc.5b01555

14. (1H-Tetrazol-5-yl)-Allenes: Building Blocks for Tetrazolyl Heterocycles

Author:
Cardoso Ana L.; Henriques Marta S. C.; Paixão José A.; Pinho e Melo Teresa M. V. D.
Source:
Journal of organic chemistry 2016 v.81 no.19 pp. 9028-9036
ISSN:
1520-6904
Subject:
aziridines; chemical bonding; chemical reactions; chlorides; cleavage (chemistry); ethylene; ketones; microwave treatment; organic chemistry; phosphorus; pyrroles; triethylamine
Abstract:
... (1H-Tetrazol-5-yl)-allenes have been prepared for the first time, and their reactivity toward aziridines explored. Reaction of a (1-benzyl-1H-tetrazol-5-yl)-phosphonium chloride and acyl chlorides in the presence of triethylamine afforded the target allenes via Wittig reaction of the in situ generated phosphorus ylide and ketenes. 1-(1-Benzyl-1H-tetrazol-5-yl)propa-1,2-diene and 3-methyl-, 3-ethyl ...
DOI:
10.1021/acs.joc.6b01679

15. (1R,2R)-DPEN-derived triazolium salts for enantioselective oxodiene Diels–Alder reactions

Author:
Zi-Qiang Rong; Min-Qiang Jia; Shu-Li You
Source:
Tetrahedron 2011 v.67 no.48 pp. 9329-9333
ISSN:
0040-4020
Subject:
chemical reactions; enantiomers; organic compounds; salts
Abstract:
... Enantioselective oxodiene Diels–Alder reactions catalyzed by (1R,2R)-DPEN-derived triazolium salts were realized successfully. With 0.5 mol % of (1R,2R)-DPEN-derived triazolium salt C and 150 mol % of Et₃N, the reactions of various α-chloroaldehydes (α-bromoaldehyde) with substituted enones led to 3,4-dihydropyridinones and their derivatives in good yields, diastereoselectivities, and enantioselec ...
DOI:
10.1016/j.tet.2011.09.129

16. (1R,6R)-2,2,6-Trimethyl-3-oxabicyclo[4.2.0]octan-4-one, a new monoterpene lactone produced by males of the cocoa borer Conotrachelus humeropictus (Col.: Curculionidae)

Author:
Daiane Szczerbowski; Gabriela G. Torrens; Mauro A.C.M. Rodrigues; Olzeno Trevisan; Sandra M.S. Gomes; Armin Tröger; Kenji Mori; Wittko Francke; Paulo H.G. Zarbin
Source:
Tetrahedron letters 2016 v.57 pp. 2842-2844
ISSN:
0040-4039
Subject:
Conotrachelus; Theobroma cacao; Theobroma grandiflorum; chemical reactions; chemical structure; headspace analysis; insects; integrated pest management; males; monoterpenoids; pests; pheromones
Abstract:
... The cocoa weevil Conotrachelus humeropictus is an economically most important pest on cocoa (Theobroma cacao) and cupuaçu (Theobroma grandiflorum) cultures. Knowledge on the pheromone system of this insect is prerequisite for the development of an integrated pest management system. GC/MS-analysis of headspace volatiles revealed the presence of three male specific compounds, which were identified t ...
DOI:
10.1016/j.tetlet.2016.05.036

17. (2+1)-Cycloaddition Reactions Give Further Evidence of the Nitrenium-like Character of 1-Aza-2-azoniaallene Salts

Author:
Al-Bataineh Nezar; Houk K. N.; Brewer Matthias; Hong Xin
Source:
Journal of organic chemistry 2017 v.82 no.7 pp. 4001-4005
ISSN:
1520-6904
Subject:
alkenes; chemical reactions; chemical structure; organic chemistry; salts
Abstract:
... Cationic 1-aza-2-azoniaallene salts react with structurally constrained alkenes in intramolecular reactions by C–H insertion at the allylic position, or by (2+1)-cycloaddition with the alkene followed by ring opening. The latter reaction gives further evidence of the nitrenium-like character of 1-aza-2-azoniaallene salts. DFT calculations show that alkene addition is intrinsically more favorable, ...
DOI:
10.1021/acs.joc.7b00407

18. (2-Formyl-1-phenylcyclopropyl)phosphonates as building blocks for (2-aminomethyl-cyclopropyl)phosphonates

Author:
Ahmed El-Gokha; Gerhard Maas
Source:
Tetrahedron 2011 v.67 no.16 pp. 2849-2857
ISSN:
0040-4020
Subject:
chemical reactions; chemical structure; esters; phosphonates; proline
Abstract:
... A diastereomeric mixture of dimethyl (2-formyl-2-methyl-1-phenylcyclopropyl)phosphonate ((Z)-6, (E)-6) was obtained by thermally induced cyclopropanation of α-methylacrolein with α-diazobenzylphosphonate 5. Application of proline or proline-derived organocatalysts accelerated the reaction, but had a minor effect on the Z/E ratio of 6. By reaction with benzylamine or methyl esters of glycine, (S)-a ...
DOI:
10.1016/j.tet.2011.02.068

19. (2S)-1-(4-Methoxyphenyl)-N-[(1R)-2-(4-methoxyphenyl)-1- methylethyl]-2-propanamine in Crude p-Methoxyamphetamine (PMA) Produced by the Leuckart Method

Author:
Dariusz Błachut; Jan K. Maurin; Wojciech Starosta; Krystyna Wojtasiewicz; Zbigniew Czarnocki
Source:
Zeitschrift für Naturforschung B 2014 v.57 no.5 pp. 593-598
ISSN:
1865-7117
Subject:
chemical compounds; chemical reactions; diastereomers; stereochemistry
Abstract:
... The synthesis and separation of both diastereoisomers of 1-(4-methoxyphenyl)-N-[2- (4-methoxyphenyl)-1-methylethyl]-2-propanamine as markers of clandestine p-methoxyamphetamine have been described. The stereochemistry of the meso diastereomer was established by crystallographic method. ...
DOI:
10.1515/znb-2002-0518

20. (2S,4R)-Hyp-(S)-Phe-OMe dipeptide supported on imidazolium tagged molecules as recoverable organocatalysts for asymmetric aldol reactions using water as reaction medium

Author:
Arturo Obregón-Zúñiga; Eusebio Juaristi
Source:
Tetrahedron 2017 v.73 pp. 5373-5380
ISSN:
0040-4020
Subject:
catalysts; chemical elements; chemical reactions; chemical structure; organic compounds; solvents; stereochemistry
Abstract:
... Four novel chiral imidazolium tagged molecules derived from dipeptide (2S,4R)-Hyp-(S)-Phe-OMe were prepared and evaluated as organocatalysts in the asymmetric aldol reaction using water as solvent. It was found that catalysts incorporating the hexanoyl linker are active down to 5 mol% and afford aldol products with up to 94% yield, up to 98:2 dr and up to 97:3 er. This chiral imidazolium catalyst ...
DOI:
10.1016/j.tet.2017.07.037

21. (2S,5R)-2-Methylaminomethyl-1-methyl-5-phenylpyrrolidine, a chiral diamine ligand for copper(ii)-catalysed Henry reactions with superb enantiocontrol

Author:
Dagmar Scharnagel; Felix Prause; Johannes Kaldun; Robert G. Haase; Matthias Breuning
Source:
Chemical communications 2014 v.50 no.50 pp. 6623-6625
ISSN:
1364-548X
Subject:
aldehydes; catalytic activity; chemical reactions; copper; heterocyclic compounds; ligands
Abstract:
... A cis-2-aminomethyl-5-phenylpyrrolidine, which is easily available from methyl Boc-l-pyroglutamate, was found to be a highly efficient chiral ligand for Cu(ii)-catalysed Henry reactions. Excellent yields (>90%) and superb levels of enantiocontrol (98.5–99.6% ee) were reached with aromatic, heteroaromatic, vinylic, and aliphatic aldehydes (36 examples). ...
DOI:
10.1039/c4cc02429j

22. (3 + 1) Annulation/Rearrangement Cascade of C,N-Cyclic Azomethine Imines and 3-Chlorooxindoles: Construction of Hexahydroindeno[2,1-c]pyrazole Spirooxindole Frameworks

Author:
Peng-Fei Zheng; Rong Zeng; Kun Jiang; Hong-Wei Li; Ying Ye; Chao Mu; Li Shuai; Qin Ouyang; Ying-Chun Chen
Source:
Organic letters 2019 v.21 no.24 pp. 10052-10056
ISSN:
1523-7052
Subject:
ambient temperature; chemical reactions; chemical structure; imines; pyrazoles
Abstract:
... The Brønsted base promoted (3 + 1) annulation reaction of C,N-cyclic azomethine imines and 3-chlorooxindoles was investigated, finally delivering complex hexahydroindeno[2,1-c] pyrazoles incorporating a spirocyclic oxindole motif after an unexpected rearrangement process. The asymmetric version of this new transformation could be accomplished, but slow racemization of the chiral product was observ ...
DOI:
10.1021/acs.orglett.9b03996

23. (3 + 2)-Annulation of p-Quinamine and Aryne: A Strategy To Construct the Multisubstituted Hydrocarbazoles

Author:
Xu Dengyu; Zhao Yulong; Song Dengpeng; Zhong Zhuliang; Feng Shangbiao; Xie Xingang; Wang Xiaolei; She Xuegong
Source:
Organic letters 2017 v.19 no.13 pp. 3600-3603
ISSN:
1523-7052
Subject:
carbon; chemical reactions; chemical structure; organic compounds
Abstract:
... A strategy for the synthesis of multisubstituted hydrocarbazoles has been developed through (3 + 2)-annulation of p-quinamines and arynes. In this way, new analogs of hydrocarbazoles with quaternary carbon center can be synthesized in satisfactory yield under mild conditions. Furthermore, this (3 + 2)-annulation can be easily scaled-up, and the products can be modified through simple transformatio ...
DOI:
10.1021/acs.orglett.7b01578

24. (3 + 3) Annulation of Nitroallylic Acetates with Stabilized Sulfur Ylides for the Synthesis of 2-Aryl Terephthalates

Author:
Lakshminarayana Satham; Irishi N. N. Namboothiri
Source:
Journal of organic chemistry 2018 v.83 no.16 pp. 9471-9477
ISSN:
1520-6904
Subject:
acetates; acetonitrile; ambient temperature; chemical reactions; enzyme inhibitors; geranylgeranyl diphosphate synthase; moieties; organic chemistry; polymers; sulfur
Abstract:
... A novel (3 + 3) annulation approach has been developed for the synthesis of 2-aryl terephthalates from nitroallylic acetates and stabilized sulfur ylides. The 2-aryl terephthalates, which are also biaryls bearing a terephthalate moiety, are formed through a cascade of reactions such as a γ-selective SN2′ reaction, γ-selective intramolecular Michael addition, and two eliminations in the presence of ...
DOI:
10.1021/acs.joc.8b00917

25. (3E,7E)-3,7-Bis(2-oxoindolin-3-ylidene)-5,7-dihydropyrrolo[2,3-f]indole-2,6(1H,3H)-dione based polymers for ambipolar organic thin film transistors

Author:
Yinghui He; Chang Guo; Bin Sun; Jesse Quinn; Yuning Li
Source:
Chemical communications 2015 v.51 no.38 pp. 8093-8096
ISSN:
1364-548X
Subject:
chemical reactions; films (materials); polymers; transistors
Abstract:
... A novel acceptor, (3E,7E)-3,7-bis(2-oxoindolin-3-ylidene)-5,7-dihydropyrrolo[2,3-f]indole-2,6(1H,3H)-dione, was reported. Donor–acceptor (D–A) polymer semiconductors using this new building block showed high ambipolar charge transport performance with hole and electron mobilities up to 0.19 and 0.09 cm² V⁻¹ s⁻¹, respectively, in thin film transistors. ...
DOI:
10.1039/c5cc01021g

26. (3E,8E)-3,8-Bis(2-oxoindolin-3-ylidene)naphtho-[1,2-b:5,6-b′]difuran-2,7(3H,8H)-dione (INDF) based polymers for organic thin-film transistors with highly balanced ambipolar charge transport characteristics

Author:
Yunfeng Deng; Bin Sun; Yinghui He; Jesse Quinn; Chang Guo; Yuning Li
Source:
Chemical communications 2015 v.51 no.70 pp. 13515-13518
ISSN:
1364-548X
Subject:
chemical reactions; films (materials); polymers; transistors
Abstract:
... Two donor–acceptor (D–A) conjugated polymers, PINDFTT and PINDFBT, based on a novel electron acceptor, (3E,8E)-3,8-bis(2-oxoindolin-3-ylidene)naphtho-[1,2-b:5,6-b′]difuran-2,7(3H,8H)-dione (INDF), are synthesized for solution processed organic thin-film transistors. Both polymers exhibited highly balanced ambipolar characteristics with hole and electron mobilities up to 0.51 cm² V⁻¹ s⁻¹ and 0.50 c ...
DOI:
10.1039/c5cc03917g

27. (4 + 3)-Cycloaddition of Donor–Acceptor Cyclopropanes with Thiochalcones: A Diastereoselective Access to Tetrahydrothiepines

Author:
André U. Augustin; J. Luca Merz; Peter G. Jones; Grzegorz Mlostoń; Daniel B. Werz
Source:
Organic letters 2019 v.21 no.23 pp. 9405-9409
ISSN:
1523-7052
Subject:
Lewis acids; catalytic activity; chemical reactions; diastereoselectivity; moieties; organic compounds; stereospecificity
Abstract:
... A general approach is described for the formation of tetrahydrothiepines using donor–acceptor cyclopropanes. Thiochalcones, functioning as sulfur-containing four-atom building blocks, were reacted in a Lewis acid catalyzed formal (4 + 3)-cycloaddition reaction with donor–acceptor cyclopropanes as three-atom building blocks. Under mild conditions various tetrahydrothiepines were synthesized in good ...
DOI:
10.1021/acs.orglett.9b03623

28. (5E/Z,7E,9)-Decatrien-2-ones, Pineapple-like Flavors from Fomitopsis betulina—Structure Elucidation and Sensorial Properties

Author:
Miriam Grosse; Tim Pendzialeck; Jörg Fohrer; Ralf G. Berger; Ulrich Krings
Source:
Journal of agricultural and food chemistry 2019 v.68 no.38 pp. 10329-10335
ISSN:
1520-5118
Subject:
Fomitopsis; carbon; chemical reactions; energy; flavor; food chemistry; fungal culture; mass spectrometry; mushrooms; nuclear magnetic resonance spectroscopy; odors; pineapples
Abstract:
... During the cultivation of the edible mushroom Fomitopsis betulina on agro-industrial side streams, a pleasant flavor strongly reminiscent of pineapple was perceived. Aroma extract dilution analyses identified two flavor components with a distinct pineapple odor. On the basis of mass spectrometric data, a Wittig reaction of (E)-penta-2,4-dien-1-yltriphosphonium bromide with ethyl levulinate was con ...
DOI:
10.1021/acs.jafc.9b06105

29. (5R,7R)-5-Methylheptadecan-7-ol: a novel sex pheromone component produced by a female lichen moth, Miltochrista calamina, in the family Arctiidae

Author:
Rei Yamakawa; Ryutaro Kiyota; Tomonori Taguri; Tetsu Ando
Source:
Tetrahedron letters 2011 v.52 no.44 pp. 5808-5811
ISSN:
0040-4039
Subject:
moths; lichens; chemical reactions; sex pheromones; alcohols; males; high performance liquid chromatography; Arctiinae; females; stereoisomers; gas chromatography-mass spectrometry
Abstract:
... A methyl-branched heptadecanol was found in the pheromone gland extract of a female lichen moth, Miltochrista calamina (Arctiidae, Lithosiinae). GC–MS analyses of the alcohol and a hydrocarbon derived from it by subsequent treatments with methanesulfonyl chloride and LiAlD₄ in microscale reactions indicated 5-methylheptadecan-7-ol (1) as one possible structure. The four stereoisomers of 1 in a rat ...
DOI:
10.1016/j.tetlet.2011.08.136

30. (6-4)-Photolyase activity requires a charge shift reaction

Author:
Thorsten Stafforst; Ulf Diederichsen
Source:
Chemical communications 2005 v. no.27 pp. 3430-3432
ISSN:
1364-548X
Subject:
chemical reactions; enzyme activity; kinetics; models; moieties; pH; thymine
Abstract:
... A model compound containing a thymine oxetane moiety linked to a flavin chromophore was investigated regarding (6-4)-photolyase activity. The need for a charge shift reaction was demonstrated by a detailed pH-dependent kinetic analysis. ...
DOI:
10.1039/b503699b

31. (6R,10S)-Pallantione: The First Ketone Identified as Sex Pheromone in Stink Bugs

Author:
Fávaro Carla F.; Soldi Rafael A.; Ando Tetsu; Aldrich Jeffrey R.; Zarbin Paulo H. G.
Source:
Organic letters 2013 v.15 no.8 pp. 1822-1825
ISSN:
1523-7052
Subject:
Pentatomidae; bioactive properties; chemical reactions; chemical structure; organic compounds; sex pheromones; soybeans; synthetic pheromones
Abstract:
... This work describes the structural elucidation of the sex pheromone of the soybean stink bug, Pallantia macunaima. The biological activity of the synthetic pheromone was demonstrated by behavioral and EAD experiments. Furthermore, the absolute configuration of the natural pheromone was determined as (6R,10S)-6,10,13-trimethyltetradecan-2-one. This is the first ketone identified as a male-produced ...
DOI:
10.1021/ol400413w

32. (AEDPH₃)·(BtaH): a novel supramolecular plaster with formaldehyde adsorption and formaldehyde/ultraviolet ray-induced luminescence switching performance

Author:
Shuo-ping Chen; Le Hu; Yu-qin Zhang; Pu Deng; Cong Li; Xi Chen; Liang-jie Yuan
Source:
Chemical communications 2011 v.48 no.4 pp. 552-554
ISSN:
1364-548X
Subject:
adsorption; chemical communication; chemical reactions; formaldehyde; luminescence; mechanical properties; plaster
Abstract:
... A novel supramolecular plaster, (AEDPH₃)·(BtaH) (1), is synthesised and characterized. The supramolecular plaster is easy to synthesise and process, and displays good mechanical properties. It can adsorb and eliminate formaldehyde (HCHO) with high efficiency and exhibits very interesting HCHO/ultraviolet ray-induced luminescence switching. ...
DOI:
10.1039/c1cc16415e

33. (Anti)aromaticity of dehydroannulenes of various ring size proved by the ring current effect in 1H NMR spectra

Author:
Erich Kleinpeter; Andreas Koch
Source:
Tetrahedron 2013 v.69 pp. 1481-1488
ISSN:
0040-4020
Subject:
chemical reactions; chemical structure; magnetic properties; nuclear magnetic resonance spectroscopy; organic compounds; protons
Abstract:
... The spatial magnetic properties (Through-Space NMR Shieldings—TSNMRS) of already synthesized dehydro[n]annulenes of various ring size (from C12 to C20) have been computed, visualized as Isochemical Shielding Surfaces (ICSS) of various size and direction, and were examined subject to present (anti)aromaticity. For this purpose the thus quantified ring current effect of the macro cycles on proximate ...
DOI:
10.1016/j.tet.2012.12.019

34. (Ar-tpy)Ruᴵᴵ(ACN)₃: A Water-Soluble Catalyst for Aldehyde Amidation, Olefin Oxo-Scissoring, and Alkyne Oxygenation

Author:
Dripta De Joarder; Subrata Gayen; Rajarshi Sarkar; Rajarshi Bhattacharya; Sima Roy; Dilip K. Maiti
Source:
Journal of organic chemistry 2019 v.84 no.13 pp. 8468-8480
ISSN:
1520-6904
Subject:
acids; aldehydes; alkynes; amides; carbon-hydrogen bond activation; catalysts; catalytic activity; chemical reactions; chemical structure; ketones; olefin; organic chemistry; ruthenium; water solubility
Abstract:
... The synthetic chemists always look for developing new catalysts, sustainable catalysis, and their applications in various organic transformations. Herein, we report a new class of water-soluble complexes, (Ar-tpy)Ruᴵᴵ(ACN)₃, utilizing designed terpyridines possessing electron-donating and -withdrawing aromatic residues for tuning the catalytic activity of the Ru(II) complex. These complexes displa ...
DOI:
10.1021/acs.joc.9b00487

35. (BEDT-TTF)₃Cu₂(C₂O₄)₃(CH₃OH)₂: an organic–inorganic hybrid antiferromagnetic semiconductor

Author:
Bin Zhang; Yan Zhang; Daoben Zhu
Source:
Chemical communications 2011 v.48 no.2 pp. 197-199
ISSN:
1364-548X
Subject:
chemical communication; chemical reactions; ferrimagnetic materials; methanol; semiconductors
Abstract:
... An organic–inorganic hybrid combining a semiconducting BEDT-TTF layer and a Jahn–Teller distorted oxalato-bridged honeycomb antiferromagnetic layer [Cu₂(C₂O₄)₃²⁻]ₙ was obtained and characterized. ...
DOI:
10.1039/c1cc15227k

36. (Bio)chemical reactions during high pressure/high temperature processing affect safety and quality of plant-based foods

Author:
Iesel Van der Plancken; Lise Verbeyst; Kristel De Vleeschouwer; Tara Grauwet; Raija-Liisa Heiniö; Fiona A. Husband; Martina Lille; Alan R. Mackie; Ann Van Loey; Kaarina Viljanen; Marc Hendrickx
Source:
Trends in food science & technology 2012 v.23 no.1 pp. 28-38
ISSN:
0924-2244
Subject:
vegetable products; food processing quality; chemical reactions; pasteurization; fruit quality; European Union; markets
Abstract:
... In recent years, the range of equipment and applications for high pressure pasteurisation has gradually increased on the European market. Sterilization under conditions of elevated pressures is in the pipeline, albeit at the research level. Knowledge on the effect of high pressure/high temperature processing on food safety and quality attributes is still too limited. This review discusses recent p ...
DOI:
10.1016/j.tifs.2011.08.004

37. (Bu₃Sn)₂–TBAF: a new combination reagent for the reduction and deuteration of aryl bromides and iodides

Author:
David C. Harrowven; Ian L. Guy; Michael I. T. Nunn
Source:
Chemical communications 2004 v. no.17 pp. 1966-1967
ISSN:
1364-548X
Subject:
bromides; chemical reactions; deuterium; deuterium oxide; halogens; iodides; new combination; organobromine compounds
Abstract:
... The combination of (Bu₃Sn)₂ and TBAF has been shown to reduce aromatic bromides and iodides in excellent yields under mild conditions. When the residual water in TBAF is exchanged for D₂O, the halogen is replaced by a deuterium atom. ...
DOI:
10.1039/b406103a

38. (CH₃)₂CuLi/Cu(OTf)₂ Mediated N- or O-Cyclization of Urea-Tethered Cyclobuta[b]indolines

Author:
Leyi Tao; Min Shi
Source:
Organic letters 2018 v.21 no.1 pp. 129-133
ISSN:
1523-7052
Subject:
chemical reactions; chemical structure; organic compounds; reaction mechanisms
Abstract:
... A (CH₃)₂CuLi/Cu(OTf)₂ mediated N- or O-cyclization of urea-tethered cyclobuta[b]indolines has been reported in this paper, giving a new synthetic protocol for the construction of pyrimido[1,6-a]indolone and cyclic imidate derivatives in moderate to good yields with a broad substrate scope under mild conditions. A plausible reaction mechanism has been also proposed on the basis of previous reports ...
DOI:
10.1021/acs.orglett.8b03565

39. (Ce,Gd)O2−δ-based dual phase membranes for oxygen separation

Author:
Alfred Junio Samson; Martin Søgaard; Peter Vang Hendriksen
Source:
Journal of membrane science 2014 v.470 pp. 178-188
ISSN:
0376-7388
Subject:
X-ray diffraction; air; asymmetric membranes; chemical reactions; liquids; microstructure; mixing; oxygen; temperature
Abstract:
... Composite membranes based on selected combinations of the ionic conductor Ce0.9Gd0.1O1.95 (CGO) and electronic/mixed conductors (Ag–CuO, LaCoO3 (LC), La0.6Sr0.4CoO3−δ (LSC), La0.6Sr0.4FeO3−δ (LSF), (La0.6Sr0.4)0.99Co0.2Fe0.8O3−δ (LSCF), and La0.75Sr0.25Cr0.97V0.03O3−δ (LSCrV)) were prepared and characterized with respect to sinterability, oxygen permeation rate, phase interaction, and microstructu ...
DOI:
10.1016/j.memsci.2014.07.028

40. (Chiral) lithium–(magnesium–)zinc and lithium–cobalt combinations as dual reagents for aromatic deproto-metalation and aryl transfer to aldehydes

Author:
David Tilly; Katia Snégaroff; Gandrath Dayaker; Floris Chevallier; Philippe C. Gros; Florence Mongin
Source:
Tetrahedron 2012 v.68 no.42 pp. 8761-8766
ISSN:
0040-4020
Subject:
alcohols; aldehydes; chemical reactions; enantiomers; iodine; temperature; tetrahydrofuran; zinc
Abstract:
... The deprotonating ability of mixed lithium–zinc or lithium–magnesium–zinc combinations containing amido and alkyl ligands in tetrahydrofuran were compared using anisole as substrate and iodine to quantitatively trap the formed arylmetal species. The results showed that the deprotonating ability is hampered if a Grignard reagent is employed to introduce the alkyl ligand, and is reduced when 2,2,6,6 ...
DOI:
10.1016/j.tet.2012.08.008

41. (C₃H₉NI)₄AgBiI₈: a direct-bandgap layered double perovskite based on a short-chain spacer cation for light absorption

Author:
Yunpeng Yao; Bo Kou; Yu Peng; Zhenyue Wu; Lina Li; Sasa Wang; Xinyuan Zhang; Xitao Liu; Junhua Luo
Source:
Chemical communications 2020 v.56 no.21 pp. 3206-3209
ISSN:
1364-548X
Subject:
cations; chemical reactions; iodides; lead; semiconductors
Abstract:
... A new iodide layered double perovskite (C₃H₉NI)₄AgBiI₈ (IPAB) has been developed based on a short-chain spacer cation, which is the first homologous compound in iodide double perovskites that adopt the Ruddlesden–Popper structure type. Importantly, IPAB is a promising environmentally friendly alternative to the recently rapidly progressing lead halide semiconductors owing to its narrow direct-band ...
DOI:
10.1039/c9cc07796k

42. (C₄H₃SCH₂NH₃)₂(CH₃NH₃)Pb₂I₇ : non-centrosymmetrical crystal structure of a bilayer hybrid perovskite

Author:
Xu-Hui Zhu; Nicolas Mercier; Amédée Riou; Philippe Blanchard; Pierre Frère
Source:
Chemical communications 2002 v. no.18 pp. 2160-2161
ISSN:
1364-548X
Subject:
chemical compounds; chemical reactions; crystal structure
Abstract:
... The analysis of the crystal stucture of (C₄H₃SCH₂NH₃)₂(CH₃NH₃)Pb₂I₇, displaying a well-ordered acentric inorganic Pb₂I₇³⁻ bilayer, is reported, and compared to the related monolayer hybrid perovskite. ...
DOI:
10.1039/b205543k

43. (Deep) blue through-space conjugated TADF emitters based on [2.2]paracyclophanes

Author:
Eduard SpulingThese authors contributed equally to this work.; Nidhi Sharma; Ifor D. W. Samuel; Eli Zysman-Colman; Stefan Bräse
Source:
Chemical communications 2018 v.54 no.67 pp. 9278-9281
ISSN:
1364-548X
Subject:
chemical compounds; chemical reactions; fluorescence
Abstract:
... The first examples of through-space conjugated thermally activated delayed fluorescence (TADF) emitters based on a [2.2]paracyclophane (PCP) skeleton with stacked (coplanar) donor–acceptor groups have been synthesized. The optoelectronic properties are studied by the relative configuration, cis (pseudo-geminal) and trans (pseudo-para), of the donor and acceptor groups. ...
DOI:
10.1039/c8cc04594a

44. (Dicyclopentadiene) platinum(II) dichloride: an efficient catalyst for the hydrosilylation reaction between alkenes and triethoxysilane

Author:
Huarui Wu; Chaoyue Zheng; Naiwu Chen; Jie Zhu; Deqing Gao
Source:
Tetrahedron letters 2017 pp. -
ISSN:
0040-4039
Subject:
alkenes; biphenyl; catalysts; chemical reactions; isomers; platinum
Abstract:
... (Dicyclopentadiene) platinum(II) dichloride was found to be an efficient hydrosilylation catalyst (homogeneous) upon a wide variety of functionalized alkenes and alkenes terminated with chemical moieties (diphenyl amino-, N-carbazol- and N-isoindoline-1,3-dione-). It is noteworthy that the hydrosilylation of aminated alkenes with triethoxysilane exhibited the yield of over 70% and the selectivity ...
DOI:
10.1016/j.tetlet.2017.03.017

45. (Diisopropylammonium)₂MnBr₄: a multifunctional ferroelectric with efficient green-emission and excellent gas sensing properties

Author:
Chunli Jiang; Ni Zhong; Chunhua Luo; Hechun Lin; Yuanyuan Zhang; Hui Peng; Chun-Gang Duan
Source:
Chemical communications 2017 v.53 no.44 pp. 5954-5957
ISSN:
1364-548X
Subject:
chemical reactions; green light; optical properties; temperature; vapors
Abstract:
... Combination of excellent optical properties and ferroelectricity of hybrid materials leads to high-performance optoelectronic devices. Here we present a new organic–inorganic hybrid compound (diisopropylammonium)₂MnBr₄ (DIPA₂MnBr₄) which shows high temperature ferroelectricity accompanied by highly efficient green-light emission. DIPA₂MnBr₄ also exhibits sensitive and selective optical response to ...
DOI:
10.1039/c7cc01107e

46. (E)- and (Z)-Stereodefined Enol Sulfate Esters Derived from α-Aryl Aldehydes: Stereocomplementary Synthesis of Styryl Sulfate Natural Products

Author:
Yu Shuai; Li Feng; Kim Sanghee
Source:
Journal of organic chemistry 2017 v.82 no.13 pp. 6992-6999
ISSN:
1520-6904
Subject:
aldehydes; chemical reactions; enols; esters; moieties; organic chemistry; stereoselectivity; sulfates; trapping
Abstract:
... A method for the stereoselective formation of enol sulfate esters from α-aryl aldehydes is described. This method involved the stereocontrolled enolization of a carbonyl group with DBU or t-BuOK followed by trapping with a reactive sulfuryl imidazolium salt, providing the corresponding styryl enol sulfate esters in good to excellent yields and stereoselectivities. This method was applied to the fi ...
DOI:
10.1021/acs.joc.7b00868

47. (E)-1,2-Difluoro-1-(pentafluoro-λ6-sulfanyl)- 2-iodoethylene

Author:
Holger Wessolowski; Gerd-Volker Röschenthaler; Rolf Winter; Gary L. Gard
Source:
Zeitschrift für Naturforschung 2014 v.46 no.1 pp. 123-125
ISSN:
0932-0776
Subject:
chemical compounds; chemical reactions; chemical structure; iodine; synthesis
Abstract:
... The first SF5-substituted perfluoro iodo alkene (E) - F₅SCF = CFI was synthesized from the phosphonium salt precursor [(E)-F₅SCF = CFPMe₃]⁺BF₄⁻ and iodine. ...
DOI:
10.1515/znb-1991-0122

48. (E)-2-Boryl 1,3-Dienes from the 10-TMS-9-BBDs: Highly Selective Reagents for the Asymmetric Synthesis of anti-α,β-Disubstituted β-Allenylamines from the Allylboration of Aldimines

Author:
González Javier R.; Soderquist John A.
Source:
Organic letters 2014 v.16 no.14 pp. 3840-3843
ISSN:
1523-7052
Subject:
acids; aldimines; chemical reactions; diastereomers; piperidines
Abstract:
... The asymmetric allylboration of N-H aldimines with optically pure trans-4-substituted-2-boryl-1,3-dienes 6 is described. These organoboranes 6 serve as near-perfect asymmetric allylborating agents for N-H aldimines for the preparation of anti-1,2-disubstituted-3,4-pentadien-1-amines 11 as essentially single diastereomers in enantiomerically pure form (>98% de, ≥98% ee). Enantiomerically pure cis-2 ...
DOI:
10.1021/ol501892a

49. (E)-Specific direct Julia-olefination of aryl alcohols without extra reducing agents promoted by bases

Author:
Chuan-Zhi Yao; Qiang-Qiang Li; Mei-Mei Wang; Xiao-Shan Ning; Yan-Biao Kang
Source:
Chemical communications 2015 v.51 no.36 pp. 7729-7732
ISSN:
1364-548X
Subject:
alcohols; aldehydes; alkenes; aromatic compounds; chemical reactions; hydrides; reducing agents
Abstract:
... An unprecedented base-promoted direct olefination of aryl alcohols with sulfones via a Julia-type reaction has been described. No extra reductants are needed for Julia reaction since alcohols work as double sources of aldehydes and the hydride. Generally high yields were given for both terminal and highly (E)-selective internal olefins. ...
DOI:
10.1039/c5cc01965f

50. (E)-α,β-unsaturated amides from tertiary amines, olefins and CO via Pd/Cu-catalyzed aerobic oxidative N-dealkylation

Author:
Renyi Shi; Hua Zhang; Lijun Lu; Pei Gan; Yuchen Sha; Heng Zhang; Qiang Liu; Matthias Beller; Aiwen Lei
Source:
Chemical communications 2015 v.51 no.15 pp. 3247-3250
ISSN:
1364-548X
Subject:
alkenes; amides; catalysts; catalytic activity; chemical reactions; chemoselectivity; palladium; secondary amines; tertiary amines
Abstract:
... A novel Pd/Cu-catalyzed chemoselective aerobic oxidative N-dealkylation/carbonylation reaction has been developed. Tertiary amines are utilized as a “reservoir” of “active” secondary amines in this transformation, which inhibits the formation of undesired by-products and the deactivation of the catalysts. This protocol allows for an efficient and straightforward construction of synthetically usefu ...
DOI:
10.1039/c4cc08925a