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You searched for: Journal Journal of the American Chemical Society Remove constraint Journal: Journal of the American Chemical Society Publication Year 2014 Remove constraint Publication Year: 2014 Source 2014 v.136 no.48 Remove constraint Source: 2014 v.136 no.48
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1. A Comprehensive Mechanistic Picture of the Isomerizing Alkoxycarbonylation of Plant Oils

Author:
Roesle, Philipp; Caporaso, Lucia; Schnitte, Manuel; Goldbach, Verena; Cavallo, Luigi; Mecking, Stefan
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16871-16881
ISSN:
1520-5126
Subject:
alcohols; energy; ethylene; isomerization; methanolysis; monounsaturated fatty acids; nuclear magnetic resonance spectroscopy; olefin; plant fats and oils
Abstract:
... Theoretical studies on the overall catalytic cycle of isomerizing alkoxycarbonylation reveal the steric congestion around the diphosphine coordinated Pd-center as decisive for selectivity and productivity. The energy profile of isomerization is flat with diphosphines of variable steric bulk, but the preference for the formation of the linear Pd-alkyl species is more pronounced with sterically dema ...
DOI:
10.1021/ja508447d

2. A Giant Molecular Spoked Wheel

Author:
May, Robert; Jester, Stefan-S.; Höger, Sigurd
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16732-16735
ISSN:
1520-5126
Subject:
graphene; octanoic acid; scanning tunneling microscopy; solubility; solvents
Abstract:
... The modular synthesis of a defined, rigid molecular spoked wheel structure with the sum formula C₁₈₇₈H₂₆₈₂ and a diameter of about 12 nm is described. The attached 96 dodecyl side chains provide the solubility of the 25 260 Da compound in common organic solvents. At the octanoic acid/highly oriented pyrolytic graphite interface, the molecules self-assemble to form an ordered 2D lattice, which is i ...
DOI:
10.1021/ja5096705

3. Alkali Metal Control over N–N Cleavage in Iron Complexes

Author:
Grubel, Katarzyna; Brennessel, William W.; Mercado, Brandon Q.; Holland, Patrick L.
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16807-16816
ISSN:
1520-5126
Subject:
cations; chemical bonding; iron; nitrides; nitrogen; potassium; reducing agents; sodium
Abstract:
... Though N₂ cleavage on K-promoted Fe surfaces is important in the large-scale Haber–Bosch process, there is still ambiguity about the number of Fe atoms involved during the N–N cleaving step and the interactions responsible for the promoting ability of K. This work explores a molecular Fe system for N₂ reduction, particularly focusing on the differences in the results obtained using different alkal ...
DOI:
10.1021/ja507442b
PubMed:
25412468
PubMed Central:
PMC4277784

4. Biofunctionalization of Si(111)7×7 by “Renewable” l-Cysteine Transitional Layer

Author:
Rahsepar, Fatemeh R.; Zhang, Lei; Farkhondeh, Hanieh; Leung, K. T.
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16909-16918
ISSN:
1520-5126
Subject:
X-radiation; adsorption; annealing; cations; cysteine; electrostatic interactions; hydrogen bonding; scanning tunneling microscopy; silicon; temperature; zwitterions
Abstract:
... Surface functionalization of an inorganic surface with bio-organic molecules is often aimed at creating a “permanent” bio-organic surface with receptor functional groups. We show here that l-cysteine can be used to transform a highly reactive Si(111)7×7 surface to not just a permanent bio-organic surface but also a semipermanent (or renewable) and a temporary bio-organic surfaces by manipulating t ...
DOI:
10.1021/ja509264t

5. Boron-Catalyzed Silylative Reduction of Quinolines: Selective sp3 C–Si Bond Formation

Author:
Gandhamsetty, Narasimhulu; Joung, Seewon; Park, Sung-Woo; Park, Sehoon; Chang, Sukbok
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16780-16783
ISSN:
1520-5126
Subject:
catalysts; nitrogen; quinolines; silanes; stereochemistry
Abstract:
... A silylative reduction of quinolines to synthetically versatile tetrahydroquinoline molecules involving the formation of a C(sp³)–Si bond exclusively β to nitrogen is described. Triarylborane is a highly efficient catalyst (up to 1000 turnovers), and silanes serve as both a silyl source and a reducing reagent. The present procedure is convenient to perform even on a large scale with excellent ster ...
DOI:
10.1021/ja510674u

6. Cobalt-Catalyzed Enantioselective Intramolecular Hydroacylation of Ketones and Olefins

Author:
Yang, Junfeng; Yoshikai, Naohiko
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16748-16751
ISSN:
1520-5126
Subject:
aldehydes; alkenes; chemical bonding; enantiomers; indans; isotopes; ketones
Abstract:
... Cobalt–chiral diphoshine catalytic systems promote intramolecular hydroacylation reactions of 2-acylbenzaldehydes and 2-alkenylbenzaldehydes to afford phthalide and indanone derivatives, respectively, in moderate to good yields with high enantioselectivities. The ketone hydroacylation did not exhibit a significant H/D kinetic isotope effect (KIE) with respect to the aldehyde C–H bond, indicating t ...
DOI:
10.1021/ja509919x

7. Cucurbit[6]uril-Based Supramolecular Assemblies: Possible Application in Radioactive Cesium Cation Capture

Author:
Chen, Kai; Kang, Yan-Shang; Zhao, Yue; Yang, Ji-Min; Lu, Yi; Sun, Wei-Yin
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16744-16747
ISSN:
1520-5126
Subject:
Cucurbitaceae; cations; cesium; metal ions
Abstract:
... Multidimensional supramolecular assemblies based on cucurbit[n]uril (n = 6 or 7) were constructed via the outer-surface interactions of cucurbit[n]urils with the polyaromatic compound 4,4′,4″-benzene-1,3,5-triyl-tribenzoate as a structure-directing agent. Most impressively, the cucurbit[6]uril-based assembly exhibits high selectivity for capture of cesium cations among the common alkali metal ions ...
DOI:
10.1021/ja5098836

8. Cu(II)–Cu(I) Synergistic Cooperation to Lead the Alkyne C–H Activation

Author:
Bai, Ruopeng; Zhang, Guanghui; Yi, Hong; Huang, Zhiliang; Qi, Xiaotian; Liu, Chao; Miller, Jeffrey T.; Kropf, A. Jeremy; Bunel, Emilio E.; Lan, Yu; Lei, Aiwen
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16760-16763
ISSN:
1520-5126
Subject:
Raman spectroscopy; X-ray absorption spectroscopy; alkynes; chemical bonding; copper; electron paramagnetic resonance spectroscopy; oxidants
Abstract:
... An efficient alkyne C–H activation and homocoupling procedure has been studied which indicates that a Cu(II)/Cu(I) synergistic cooperation might be involved. In situ Raman spectroscopy was employed to study kinetic behavior, drawing the conclusion that Cu(I) rather than Cu(II) participates in the rate-determining step. IR, EPR, and X-ray absorption spectroscopy evidence were provided for structura ...
DOI:
10.1021/ja5097489

9. Determination of Redox Reaction Rates and Orders by In Situ Liquid Cell Electron Microscopy of Pd and Au Solution Growth

Author:
Sutter, Eli A.; Sutter, Peter W.
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16865-16870
ISSN:
1520-5126
Subject:
aqueous solutions; electrons; equations; gold; image analysis; nanoparticles; palladium; redox reactions; transmission electron microscopy
Abstract:
... In-situ liquid cell transmission and scanning transmission electron microscopy (TEM/STEM) experiments are important, as they provide direct insight into processes in liquids, such as solution growth of nanoparticles, among others. In liquid cell TEM/STEM redox reaction experiments, the hydrated electrons e–ₐq created by the electron beam are responsible for the reduction of metal-ion complexes. He ...
DOI:
10.1021/ja508279v

10. Electron-Induced Conversion of Silylones to Six-Membered Cyclic Silylenes

Author:
Roy, Sudipta; Mondal, Kartik Chandra; Krause, Lennard; Stollberg, Peter; Herbst-Irmer, Regine; Stalke, Dietmar; Meyer, Jann; Stückl, A. Claudia; Maity, Bholanath; Koley, Debasis; Vasa, Suresh Kumar; Xiang, Sheng Qi; Linser, Rasmus; Roesky, Herbert W.
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16776-16779
ISSN:
1520-5126
Subject:
chemical bonding; electron paramagnetic resonance spectroscopy; electrons; ligands; oxidation; potassium; silicon
Abstract:
... A silicon atom in the zero oxidation state stabilized by two carbene ligands is known as siladicarbene (silylone). There are two pairs of electrons on the silicon atom in silylone. This was recently confirmed by both experimental and theoretical charge density investigations. The silylone is stable up to 195 °C in an inert atmosphere. However, a substoichiometric amount (33 mol%) of potassium meta ...
DOI:
10.1021/ja510427r

11. Facile Synthesis of Ba1–xKxFe2As2 Superconductors via Hydride Route

Author:
Zaikina, Julia V.; Batuk, Maria; Abakumov, Artem M.; Navrotsky, Alexandra; Kauzlarich, Susan M.
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16932-16939
ISSN:
1520-5126
Subject:
X-ray diffraction; barium; hydrides; hydrogen; mixing; potassium; powders; temperature; transmission electron microscopy
Abstract:
... We have developed a fast, easy, and scalable synthesis method for Ba₁–ₓKₓFe₂As₂ (0 ≤ x ≤ 1) superconductors using hydrides BaH₂ and KH as a source of barium and potassium metals. Synthesis from hydrides provides better mixing and easier handling of the starting materials, consequently leading to faster reactions and/or lower synthesis temperatures. The reducing atmosphere provided by the evolved h ...
DOI:
10.1021/ja509907r

12. Ferromagnetic Ordering in Superatomic Solids

Author:
Lee, Chul-Ho; Liu, Lian; Bejger, Christopher; Turkiewicz, Ari; Goko, Tatsuo; Arguello, Carlos J.; Frandsen, Benjamin A.; Cheung, Sky C.; Medina, Teresa; Munsie, Timothy J. S.; D’Ortenzio, Robert; Luke, Graeme M.; Besara, Tiglet; Lalancette, Roger A.; Siegrist, Theo; Stephens, Peter W.; Crowther, Andrew C.; Brus, Louis E.; Matsuo, Yutaka; Nakamura, Eiichi; Uemura, Yasutomo J.; Kim, Philip; Nuckolls, Colin; Steigerwald, Michael L.; Roy, Xavier
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16926-16931
ISSN:
1520-5126
Subject:
fullerene; magnetic properties; nickel; phase transition; temperature
Abstract:
... In order to realize significant benefits from the assembly of solid-state materials from molecular cluster superatomic building blocks, several criteria must be met. Reproducible syntheses must reliably produce macroscopic amounts of pure material; the cluster-assembled solids must show properties that are more than simply averages of those of the constituent subunits; and rational changes to the ...
DOI:
10.1021/ja5098622

13. General Strategy for Fabricating Thoroughly Mesoporous Nanofibers

Author:
Hou, Huilin; Wang, Lin; Gao, Fengmei; Wei, Guodong; Tang, Bin; Yang, Weiyou; Wu, Tom
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16716-16719
ISSN:
1520-5126
Subject:
biocompatible materials; cost effectiveness; foaming; nanofibers; photocatalysis; porous media; titanium dioxide; vapors
Abstract:
... Recently, preparation of mesoporous fibers has attracted extensive attentions because of their unique and broad applications in photocatalysis, optoelectronics, and biomaterials. However, it remains a great challenge to fabricate thoroughly mesoporous nanofibers with high purity and uniformity. Here, we report a general, simple and cost-effective strategy, namely, foaming-assisted electrospinning, ...
DOI:
10.1021/ja508840c

14. Highly Efficient Activation of Organosilanes with η2-Aldehyde Nickel Complexes: Key for Catalytic Syntheses of Aryl-, Vinyl-, and Alkynyl-Benzoxasiloles

Author:
Hoshimoto, Yoichi; Yabuki, Hayato; Kumar, Ravindra; Suzuki, Haruka; Ohashi, Masato; Ogoshi, Sensuke
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16752-16755
ISSN:
1520-5126
Subject:
nickel; nuclear magnetic resonance spectroscopy; silicates
Abstract:
... An η²-aldehyde nickel complex was utilized as an effective activator for an organosilane in order to generate a hypervalent silicate reactant for the first time. This method was successfully applied to the highly efficient syntheses of 3-aryl-, vinyl-, and alkynyl-2,1-benzoxasiloles from benzaldehydes with aryl-, vinyl-, and alkynylsilyl groups at the ortho position. Initial mechanistic studies re ...
DOI:
10.1021/ja510089c

15. Highly Selective Solar-Driven Methanol from CO2 by a Photocatalyst/Biocatalyst Integrated System

Author:
Yadav, Rajesh K.; Oh, Gyu Hwan; Park, No-Joong; Kumar, Abhishek; Kong, Ki-jeong; Baeg, Jin-Ook
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16728-16731
ISSN:
1520-5126
Subject:
biocatalysts; carbon dioxide; enzymes; graphene; methanol; photocatalysts
Abstract:
... The successful development of a photocatalyst/biocatalyst integrated system that carries out selective methanol production from CO₂ is reported herein. The fine-tuned system was derived from a judicious combination of graphene-based visible light active photocatalyst (CCG-IP) and sequentially coupled enzymes. The covalent attachment of isatin-porphyrin (IP) chromophore to chemically converted grap ...
DOI:
10.1021/ja509650r

16. Immunogenicity Study of Globo H Analogues with Modification at the Reducing or Nonreducing End of the Tumor Antigen

Author:
Lee, Hsin-Yu; Chen, Chien-Yu; Tsai, Tsung-I; Li, Shiou-Ting; Lin, Kun-Hsien; Cheng, Yang-Yu; Ren, Chien-Tai; Cheng, Ting-Jen R.; Wu, Chung-Yi; Wong, Chi-Huey
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16844-16853
ISSN:
1520-5126
Subject:
adjuvants; animal ovaries; antibodies; breasts; clinical trials; cytotoxicity; epitopes; fucose; glucose; glycolipids; immune response; immunoglobulin G; mice; neoplasm cells; prostatic neoplasms; vaccine development; vaccines
Abstract:
... Globo H-based therapeutic cancer vaccines have been tested in clinical trials for the treatment of late stage breast, ovarian, and prostate cancers. In this study, we explored Globo H analogue antigens with an attempt to enhance the antigenic properties in vaccine design. The Globo H analogues with modification at the reducing or nonreducing end were synthesized using chemoenzymatic methods, and t ...
DOI:
10.1021/ja508040d

17. Intracellular CO Release from Composite of Ferritin and Ruthenium Carbonyl Complexes

Author:
Fujita, Kenta; Tanaka, Yuya; Sho, Takeya; Ozeki, Shuichi; Abe, Satoshi; Hikage, Tatsuo; Kuchimaru, Takahiro; Kizaka-Kondoh, Shinae; Ueno, Takafumi
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16902-16908
ISSN:
1520-5126
Subject:
biocompatible materials; carbon monoxide; encapsulation; ferritin; half life; protein engineering; ruthenium; transcription factor NF-kappa B
Abstract:
... Protein cages have been utilized as templates in the development of biomaterials. Here we report protein engineering of the ferritin (Fr) cage for encapsulating carbon monoxide releasing molecules (CORMs) and release of CO gas which serves as a cell signaling molecule. The protein cages enable us to increase the half-life for CO release, providing a release rate that is 18-fold slower than the rat ...
DOI:
10.1021/ja508938f

18. Intramolecular Iron-Mediated C–H Bond Heterolysis with an Assist of Pendant Base in a [FeFe]-Hydrogenase Model

Author:
Zheng, Dehua; Wang, Ning; Wang, Mei; Ding, Shengda; Ma, Chengbing; Darensbourg, Marcetta Y.; Hall, Michael B.; Sun, Licheng
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16817-16823
ISSN:
1520-5126
Subject:
active sites; crystal structure; disulfide bonds; ferredoxin hydrogenase; hydrogen; iron; models
Abstract:
... Although many metalloenzymes containing iron play a prominent role in biological C–H activation processes, to date iron-mediated C(sp³)–H heterolysis has not been reported for synthetic models of Fe/S-metalloenzymes. In contrast, ample precedent has established that nature’s design for reversible hydrogen activation by the diiron hydrogenase ([FeFe]-H₂ase) active site involves multiple irons, sulf ...
DOI:
10.1021/ja5078014

19. Ir-Catalyzed Reverse Prenylation of 3-Substituted Indoles: Total Synthesis of (+)-Aszonalenin and (−)-Brevicompanine B

Author:
Ruchti, Jonathan; Carreira, Erick M.
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16756-16759
ISSN:
1520-5126
Subject:
indoles; tryptophan
Abstract:
... The selective reverse prenylation of 3-substituted-1H-indoles at C3 is described. The iridium-catalyzed reaction proceeds with high branched to linear selectivity (>20:1) for a variety of indoles. In addition, a diastereoselective reverse prenylation of tryptophan methyl ester is disclosed, and its synthetic utility is demonstrated in the synthesis of (+)-aszonalenin and (−)-brevicompanine B. ...
DOI:
10.1021/ja509893s

20. Ligand-Controlled, Tunable Silver-Catalyzed C–H Amination

Author:
Alderson, Juliet M.; Phelps, Alicia M.; Scamp, Ryan J.; Dolan, Nicholas S.; Schomaker, Jennifer M.
Source:
Journal of the American Chemical Society 2014 v.136 no.48 pp. 16720-16723
ISSN:
1520-5126
Subject:
catalysts; chemical bonding; ligands; silver
Abstract:
... The development of readily tunable and regioselective C–H functionalization reactions that operate solely through catalyst control remains a challenge in modern organic synthesis. Herein, we report that simple silver catalysts supported by common nitrogenated ligands can be used to tune a nitrene transfer reaction between two different types of C–H bonds. The results reported herein represent the ...
DOI:
10.1021/ja5094309
PubMed:
25386769
PubMed Central:
PMC4277762