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1. Characteristics and distribution of phosphorus in surface sediments of a shallow lake

Author:
Ziwei Long; Zehua Ji; Yuansheng Pei
Source:
Journal of environmental sciences (China) 2023 v.124 pp. 50-60
ISSN:
1001-0742
Subject:
esters,   etc   ; agricultural pollution; bioavailability; biogeochemical cycles; lakes; nuclear magnetic resonance spectroscopy; organic matter; orthophosphates; pH; principal component analysis; risk; rivers; sediments; China;     Show all 14 Subjects
Abstract:
... Phosphorus (P) in sediments plays an important role in shallow lake ecosystems and has a major effect on the lake environment. The mobility and bioavailability of P primarily depend on the contents of different P forms, which in turn depend on the sedimentary environment. Here, sediment samples from Baiyangdian (BYD) lake were collected and measured by the Standards, Measurements, and Testing proc ...
DOI:
10.1016/j.jes.2021.10.012

2. Visible light-induced radical cascade reaction of acryloylbenzamides with N-hydroxyphthalimide esters

Author:
Xingxing Cai; Yihuo Liu; Siyu Ding; Jiahui Fu; Jinghua Li; Dongping Cheng; Xiaoliang Xu
Source:
Tetrahedron letters 2022 v.95 pp. 153722
ISSN:
0040-4039
Subject:
esters,   etc   ; light; photocatalysts;     Show all 3 Subjects
Abstract:
... An efficient and mild cascade reaction of acryloylbenzamides with N-hydroxyphthalimide (NHPI) esters is disclosed. It goes through radical addition and subsequent cyclization to give 4-alkylated isoquinolinediones in the presence of visible light and photocatalyst Ir[dF(CF₃)ppy₂](dtbbpy)PF₆. ...
DOI:
10.1016/j.tetlet.2022.153722

3. A succinct synthesis of (25R)-cholesta-5,7-diene-3β,26-diol from ergosterol

Author:
Dharma Theja Nannapaneni; Kiran Chinthapally; Ishita Hatial; Brandon L. Ashfeld; Brian S.J. Blagg
Source:
Tetrahedron letters 2022 v.103 pp. 153974
ISSN:
0040-4039
Subject:
esters,   etc   ; aldehydes; ergosterol;     Show all 3 Subjects
Abstract:
... An efficient seven-step procedure is described for the synthesis of (25R)-cholesta-5,7-diene-3β,26-diol from commercially available ergosterol in an overall yield of 25%. The synthesis features Julia-Kocienski olefination of the aldehyde with benzothiazole sulfone ester in presence of LiHMDS followed by reduction of the alkene. ...
DOI:
10.1016/j.tetlet.2022.153974

4. Asymmetric Synthesis of Tertiary and Secondary Cyclopropyl Boronates via Cyclopropanation of Enantioenriched Alkenyl Boronic Esters

Author:
Álvaro Gutiérrez-Bonet; Stasik Popov; Marion H. Emmert; Jonathan M. E. Hughes; Andrew F. Nolting; Serge Ruccolo; Yunyi Wang
Source:
Organic letters 2022 v.24 no.19 pp. 3455-3460
ISSN:
1523-7052
Subject:
esters,   etc   ; derivatization; stereoselective synthesis;     Show all 3 Subjects
Abstract:
... The cyclopropanation of alkenyl boronates and subsequent derivatization of the boronate handle are a convenient strategy to quickly build molecular complexity and access diverse compounds with a high sp³ fraction. Herein, we describe the asymmetric cyclopropanation of enantioenriched hydrobenzoin-derived alkenyl boronic esters toward the synthesis of tertiary and secondary cyclopropyl boronates. ...
DOI:
10.1021/acs.orglett.2c01018

5. Palladium-catalyzed radical cascade cyanoalkylsulfonylation/cyclization of 3-arylethynyl-[1,1′-biphenyl]-2-carbonitriles with cyclobutanone oxime esters and DABSO

Author:
Nengneng Zhou; Qiankun Xu; Ziqin Xia; Kaimo Kuang; Sixin Wu; Wenping Li; Man Zhang
Source:
Chemical communications 2022 v.58 no.14 pp. 2335-2338
ISSN:
1364-548X
Subject:
esters,   etc   ; chemical communication; phenanthridines;     Show all 3 Subjects
Abstract:
... A palladium-catalyzed radical cascade cyanoalkylsulfonylation/cyclization of 3-arylethynyl-[1,1′-biphenyl]-2-carbonitriles with DABCO·(SO₂)₂ and cyclobutanone oxime esters via cleavage of a C–C single bond and insertion of SO₂ was described. A series of cyanoalkylsulfone-containing cyclopenta[gh]phenanthridines were obtained in moderate-to-good yields, thus featuring mild reaction conditions, a br ...
DOI:
10.1039/d1cc06825c

6. Defluorinative C–C Bond-Forming Reaction of Trifluoromethyl Alkenes with gem-(Diborylalkyl)lithiums

Author:
Haeun Kim; Yujin Jung; Seung Hwan Cho
Source:
Organic letters 2022 v.24 no.14 pp. 2705-2710
ISSN:
1523-7052
Subject:
esters,   etc   ; alkenes; lithium; utilities;     Show all 4 Subjects
Abstract:
... We report the transition-metal-free defluorinative C–C bond-forming reaction of trifluoromethyl alkenes with gem-(diborylalkyl)lithiums. This synthetic strategy provides access to a variety of 4,4-difluoro homoallylic diboronate esters, which serve as versatile intermediates in the efficient preparation of valuable gem-difluoroalkene derivatives. Further synthetic modifications are conducted to de ...
DOI:
10.1021/acs.orglett.2c00809

7. Strategies for the direct oxidative esterification of thiols with alcohols

Author:
Manzarbanou Asnaashariisfahani; Bayan Azizi; Mohammad Reza Poor Heravi; Elham Mohammadi; Sattar Arshadi; Esmail Vessally
Source:
RSC advances 2022 v.12 no.23 pp. 14521-14534
ISSN:
2046-2069
Subject:
esters,   etc   ; alcohols; esterification; thiols;     Show all 4 Subjects
Abstract:
... This review paper provides an overview of the main strategies for the oxidative esterification of thiols with alcohols. The review is divided into two major parts according to final products. The first includes the methods for the synthesis of sulfinic esters, while the second contains the procedures for the fabrication of sulfonic ester derivatives. ...
DOI:
10.1039/d1ra08058j

8. Stereodivergent Synthesis of 1,3-Dienes via Protodeboronation of Homoallenylboronic Esters

Author:
Ryota Sakamoto; Minami Odagi; Atsuto Izumiseki; Kaname Konuki; Kazuo Nagasawa
Source:
Journal of organic chemistry 2022 v.87 no.12 pp. 8084-8098
ISSN:
1520-6904
Subject:
esters,   etc   ; journals; olefin; organic chemistry;     Show all 4 Subjects
Abstract:
... Vinylboronic esters and allylboronic esters are well known to afford olefins by protodeboronation, and therefore homoallenylboronic esters should be similarly available as precursors for 1,3-dienes, but this strategy has not been well explored due to the limited availability of homoallenylboronic esters. Here, we describe a versatile synthesis of homoallenylboronic esters via lithiation–borylation ...
DOI:
10.1021/acs.joc.2c00744

9. Palladium-catalyzed intermolecular alkynylcarbonylation of unactivated alkenes: easy access to β-alkynylcarboxylic esters

Author:
Xiang Li; Pinhong Chen; Guosheng Liu
Source:
Chemical communications 2022 v.58 no.15 pp. 2544-2547
ISSN:
1364-548X
Subject:
esters,   etc   ; alkenes; chemical communication; regioselectivity;     Show all 4 Subjects
Abstract:
... A palladium-catalyzed intermolecular alkynylcarbonylation of unactivated alkenes has been established with ethynyl benziodoxolones (EBXs) as alkynylation reagents, providing β-alkynylcarboxylic esters efficiently from simple alkenes. The reaction features moderate to excellent regioselectivity and excellent functional group compatibility under mild reaction conditions. ...
DOI:
10.1039/d1cc07092d

10. Visible-Light-Irradiated Cascade Reaction of Indole-Tethered Alkenes to Access Tetracyclic Tetrahydro-γ-carbolines

Author:
Haibo Mei; Aiyao Liu; Jingrui He; Yingjie Yu; Jianlin Han
Source:
Organic letters 2022 v.24 no.14 pp. 2630-2635
ISSN:
1523-7052
Subject:
esters,   etc   ; alkenes; design; methodology; photocatalysis;     Show all 5 Subjects
Abstract:
... A series of indole-derived alkenes have been designed and applied in a photocatalytic cascade reaction with bromodifluoroacetate esters, affording an unknown type of tetracyclic tetrahydro-γ-carboline derivative in up to 90% yields. Mechanistic studies suggest that the reaction proceeds with tetrahydro-γ-carboline as a key intermediate. The reaction tolerates a diverse pool of substrates, which pr ...
DOI:
10.1021/acs.orglett.2c00626

11. Self-assembly pathways in a triphenylalanine peptide capped with aromatic groups

Author:
Maria M. Pérez-Madrigal; Ana M. Gil; Jordi Casanovas; Ana I. Jiménez; Lorena P. Macor; Carlos Alemán
Source:
Colloids and surfaces 2022 v.216 pp. 112522
ISSN:
0927-7765
Subject:
esters,   etc   ; colloids; fields; peptides; surfaces; ultrasonics;     Show all 6 Subjects
Abstract:
... Peptide derivatives and, most specifically, their self-assembled supramolecular structures are being considered in the design of novel biofunctional materials. Although the self-assembly of triphenylalanine homopeptides has been found to be more versatile than that of homopeptides containing an even number of residues (i.e. diphenylalanine and tetraphenylalanine), only uncapped triphenylalanine (F ...
DOI:
10.1016/j.colsurfb.2022.112522

12. Cu-mediated vs. Cu-free selective borylation of aryl alkyl sulfones

Author:
Mingming Huang; Man Tang; Jiefeng Hu; Stephen A. Westcott; Udo Radius; Todd B. Marder
Source:
Chemical communications 2022 v.58 no.3 pp. 395-398
ISSN:
1364-548X
Subject:
esters,   etc   ; catalysts; chemical communication; salting; salts;     Show all 5 Subjects
Abstract:
... A Cu-catalysed borylation of aryl alkyl sulfones was developed for the high yield synthesis of versatile arylboronic esters using a readily prepared NHC–Cu catalyst. In addition, the selective cleavage of either alkyl(C)–sulfonyl or aryl(C)–sulfonyl bonds of a cyclic sulfone via Cu-free or Cu-mediated processes generates the corresponding sulfinate salts, which can be further derivatised to provid ...
DOI:
10.1039/d1cc06144e

13. Improved phase purity and film quality in quasi-2D perovskite light-emitting diodes by an additive with the trimethacrylate group

Author:
Xiaofeng Huang; Wu Liu; Wei Wang; Yao Lu; Jie Dong; Yueqiao Li; Dong Wei; Bo Qiao; Suling Zhao; Zheng Xu; Dandan Song
Source:
RSC advances 2022 v.12 no.5 pp. 3081-3089
ISSN:
2046-2069
Subject:
esters,   etc   ; additives; light emitting diodes; mixing;     Show all 4 Subjects
Abstract:
... Quasi-2D perovskites are potential materials for optoelectronics like light-emitting diodes (LEDs); compared to their 3D counterparts, they are considered more stable against the atmosphere and more efficient in exciton confining. However, the simultaneous formation of different phases in the quasi-2D perovskite film, i.e., the phase impurity issue, lowers the device performance. We propose using ...
DOI:
10.1039/d1ra09040b

14. NHC-Catalyzed [2 + 4] Annulation of Alkynyl Ester with Chalcone

Author:
Fangfang Lu; Yangxu Chen; Xue Song; Chenxia Yu; Tuanjie Li; Kai Zhang; Changsheng Yao
Source:
Journal of organic chemistry 2022 v.87 no.10 pp. 6902-6909
ISSN:
1520-6904
Subject:
esters,   etc   ; chalcone; journals; ketones; organic chemistry;     Show all 5 Subjects
Abstract:
... An NHC-catalyzed [2 + 4] cyclization of alkynyl ester with α,β-unsaturated ketone to form a pyran scaffold was developed successfully. The cheap and easily available starting materials, mild reaction conditions, moderate to excellent yields, and high atom economy make this strategy attractive for the syntheses of highly substituted 4H-pyran derivatives. ...
DOI:
10.1021/acs.joc.2c00022

15. Access to n-pentenyl tetra- and pentasaccharide analogues of the antitumor drug PI-88 based on 1,2-methyl orthoester glycosyl donors

Author:
Juan Ventura; Clara Uriel; Ana M. Gómez; J. Cristobal López
Source:
Carbohydrate research 2022 v.516 pp. 108557
ISSN:
0008-6215
Subject:
ortho esters,   etc   ; antineoplastic agents; glycosides; regioselectivity; research;     Show all 5 Subjects
Abstract:
... Convergent synthetic routes to PI-88 tetra- and pentasaccharide-component analogues, have been developed featuring regioselective glycosylations of mannose-polyol n-pentenyl glycosides (NPG) acceptors with 1,2-methyl orthoesters (MeOE) glycosyl donors. ...
DOI:
10.1016/j.carres.2022.108557

16. Directed Ni-Catalyzed Reductive Arylation of Aliphatic C–H Bonds

Author:
Zhi-Yun Liu; Silas P. Cook
Source:
Organic letters 2022 v.24 no.18 pp. 3313-3318
ISSN:
1523-7052
Subject:
esters,   etc   ; Lewis acids; arylation; hydroxamic acids; methodology;     Show all 5 Subjects
Abstract:
... Herein, we describe the nickel-catalyzed reductive arylation of remote C(sp³)–H bonds with aryl electrophiles. The reaction targets secondary and tertiary C(sp³)–H bonds to deliver all-carbon quaternary centers. The success of this method relies on a novel amidyl radical precursor that tolerates reducing conditions, namely O-oxalate hydroxamic acid esters. ...
DOI:
10.1021/acs.orglett.2c00447

17. Plasma flow chemistry for direct N-acylation of amines by esters

Author:
Elias Abedelnour; Stephanie Ognier; Mengxue Zhang; Laurent Schio; Olivier Venier; Janine Cossy; Michael Tatoulian
Source:
Chemical communications 2022 v.58 no.52 pp. 7281-7284
ISSN:
1364-548X
Subject:
esters,   etc   ; amides; amines; blood chemistry; chemical communication;     Show all 5 Subjects
Abstract:
... The direct N-acylation of amines by esters in a microreactor is described using argon plasma, thereby producing amides in good to excellent yields. ...
DOI:
10.1039/d2cc01940j

18. α-Iodo-α,β-Unsaturated Ketones as Vicinal Dielectrophiles: Their Reactions with Dinucleophiles Provide New Annulation Protocols for the Formation of Carbo- and Heterocyclic Ring Systems

Author:
Yu Chen; Michael G. Gardiner; Ping Lan; Martin G. Banwell
Source:
Journal of organic chemistry 2022 v.87 no.9 pp. 6146-6160
ISSN:
1520-6904
Subject:
esters,   etc   ; heterocyclic compounds; journals; ketones; organic chemistry;     Show all 5 Subjects
Abstract:
... α-Iodo-α,β-unsaturated ketones such as compound 1 serve as vicinal dielectrophiles and react with a range of dinucleophiles including pentane-2,4-dione and 1,3-indandione to produce [3 + 2]- and [2 + 1]-adducts such as 5 and 38, respectively. [4 + 2]- and [5 + 2]-cycloadducts have been obtained from compound 1 by related means. Preliminary studies reveal that α-iodinated α,β-unsaturated esters can ...
DOI:
10.1021/acs.joc.2c00383

19. Asymmetric Total Syntheses of (−)-Lycoramine, (−)-Lycoraminone, (−)-Narwedine, and (−)-Galanthamine

Author:
Satyajit Majumder; Abhinay Yadav; Souvik Pal; Arindam Khatua; Alakesh Bisai
Source:
Journal of organic chemistry 2022 v.87 no.12 pp. 7786-7797
ISSN:
1520-6904
Subject:
ortho esters,   etc   ; Amaryllidaceae; allyl alcohol; cyclohexenes; organic chemistry;     Show all 5 Subjects
Abstract:
... A concise asymmetric total synthesis of naturally occurring Amaryllidaceae alkaloids sharing dihydrobenzofuran scaffolds, (−)-galanthamine (1a), (−)-lycoramine (1b), (−)-narwedine (2a), and (−)-lycoraminone (2b), is reported. Orthoester Johnson–Claisen rearrangement of allyl alcohol (+)-9 (98% ee) in diisopropylethylamine furnished enantioenriched cyclohexene (+)-8 (97.4% ee) with a quaternary ste ...
DOI:
10.1021/acs.joc.2c00420

20. Indium-Catalyzed Formal Carbon–Halogen Bond Insertion: Synthesis of α-Halo-α,α-disubstituted Esters from Benzylic Halides and Diazo Esters

Author:
Fei Wang; Yoshihiro Nishimoto; Makoto Yasuda
Source:
Organic letters 2022 v.24 no.8 pp. 1706-1710
ISSN:
1523-7052
Subject:
esters,   etc   ; catalytic activity; diazo compounds; indium; methodology; yields;     Show all 6 Subjects
Abstract:
... One-carbon-unit insertion into carbon–halogen (C–X) bonds accompanied by the formation of a new C–X bond and carbon–chain elongation is a powerful synthetic method of complex organohalides. Herein, we developed an indium trihalide catalyzed formal insertion of diazo esters into a C–X (X = Cl, Br, I) bond. In the present system, the reactions of α-aryl diazo esters with benzylic chlorides, bromides ...
DOI:
10.1021/acs.orglett.2c00343