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26 Feb 13:04

[ASAP] Highly Dispersed Rh/NbOx Invoking High Catalytic Performances for the Valorization of Lignin Monophenols and Lignin Oil into Aromatics

by Weixiang Guan, Xiao Chen, Chi Wing Tsang, Haoquan Hu, and Changhai Liang

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ACS Sustainable Chemistry & Engineering
DOI: 10.1021/acssuschemeng.0c08478
22 Feb 07:05

Conversion of Dinitrogen into Nitrile: Cross‐Metathesis of N2‐Derived Molybdenum Nitride with Alkynes

by Jinyi Song, Qian LIAO, Xin Hong, Li Jin, Nicolas Mézailles
Conversion of Dinitrogen into Nitrile: Cross-Metathesis of N2-Derived Molybdenum Nitride with Alkynes

The combination of N2 splitting on a Mo complex followed by nitrile–alkyne cross-metathesis results in the direct synthesis of nitrile from dinitrogen under mild conditions. This provides a new strategy for functionalizing N2-derived metal nitrido complexes.


Abstract

The direct synthesis of nitrile from N2 under mild conditions is of great importance and has attracted much interest. Herein, we report a direct conversion of N2 into nitrile via a nitrile–alkyne cross-metathesis (NACM) process involving a N2-derived Mo nitride. Treatment of the Mo nitride with alkyne in the presence of KOTf afforded an alkyne-coordinated nitride, which was then transformed into MoV carbyne and the corresponding nitrile upon 1 e− oxidation. Both aryl- and alkyl-substituted alkynes underwent this process smoothly. Experiments and DFT calculations have proved that the oxidation state of the Mo center plays a crucial role. This method does not rely on the nucleophilicity of the N2-derived metal nitride, offering a novel strategy for N2 fixation chemistry.

18 Feb 13:31

[ASAP] Cleavage of Carboxylic Esters by Aluminum and Iodine

by Dayong Sang, Huaxin Yue, Yang Fu, and Juan Tian

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The Journal of Organic Chemistry
DOI: 10.1021/acs.joc.1c00034
18 Feb 13:30

[ASAP] Biobased C6-Furans in Organic Synthesis and Industry: Cycloaddition Chemistry as a Key Approach to Aromatic Building Blocks

by Fedor A. Kucherov, Leonid V. Romashov, Gleb M. Averochkin, and Valentine P. Ananikov

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ACS Sustainable Chemistry & Engineering
DOI: 10.1021/acssuschemeng.0c09229
18 Feb 13:25

Nucleation captured on camera

17 Feb 08:38

Eco-friendly and sustainable processing of wood-based materials

Green Chem., 2021, 23,2198-2232
DOI: 10.1039/D0GC04430J, Critical Review
Emmanuel Isaac Akpan, Bernd Wetzel, Klaus Friedrich
Eco-friendly alternative processes are required for functionally modified wood to maintain low embodied energy and near zero emission levels.
The content of this RSS Feed (c) The Royal Society of Chemistry
17 Feb 08:36

[ASAP] Expanding the Boundary of Biorefinery: Organonitrogen Chemicals from Biomass

by Xi Chen, Song Song, Haoyue Li, Gökalp Gözaydın, and Ning Yan

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Accounts of Chemical Research
DOI: 10.1021/acs.accounts.0c00842
13 Feb 09:27

[ASAP] Residual Solvent Signal of CDCl3 as a qNMR Internal Standard for Application in Organic Chemistry Laboratory

by Ruslan Muhamadejev, Renate Melngaile, Paula Paegle, Ieva Zibarte, Marina Petrova, Kristaps Jaudzems, and Janis Veliks
ceverelst

Strange that such a volatile "internal standard" gives good results

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The Journal of Organic Chemistry
DOI: 10.1021/acs.joc.0c02744
13 Feb 07:26

[ASAP] A Multicomponent Approach toward Angularly Fused/Linear Bitriazoles: A Cascade Cornforth Rearrangement and Triazolization

by Santhini Pulikkal Veettil, Shandev Pookkandam Parambil, Max Van Hoof, and Wim Dehaen

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The Journal of Organic Chemistry
DOI: 10.1021/acs.joc.0c03014
13 Feb 07:21

Mild and Robust Stille Reactions in Water using Parts Per Million Levels of a Triphenylphosphine‐Based Palladacycle

by Balaram S. Takale, Ruchita R. Thakore, Gianluca Casotti, Xaiohan Li, Fabrice Gallou, Bruce H. Lipshutz
Mild and Robust Stille Reactions in Water using Parts Per Million Levels of a Triphenylphosphine‐Based Palladacycle

Highly valued Stille couplings can now be done not only in water under mild reaction conditions, but with only 500–1000 ppm of Pd ligated with triphenylphosphine, derived from a new and readily prepared palladacycle.


Abstract

An inexpensive and new triphenylphosphine‐based palladacycle has been developed as a pre‐catalyst, leading to highly effective Stille cross‐coupling reactions in water under mild reaction conditions. Only 500–1000 ppm of Pd suffices for couplings involving a variety of aryl/heteroaryl halides with aryl/hetaryl stannanes. Several drug intermediates can be prepared using this catalyst in aqueous nanoreactors formed by 2 wt % Brij‐30 in water.

13 Feb 07:18

Dearomatization‐Rearomatization Strategy for ortho‐Selective Alkylation of Phenols with Primary Alcohols

by Jianjin Yu, Chao‐Jun Li, Huiying Zeng
Dearomatization‐Rearomatization Strategy for ortho‐Selective Alkylation of Phenols with Primary Alcohols

A dearomatization‐rearomatization strategy was developed for palladium‐catalyzed cross‐coupling reactions of phenols and inexpensive primary alcohols to site‐specifically generate ortho‐alkyl‐substituted phenols. Water was the sole by‐product of the reaction, making it a green method for site‐specific synthesis of these phenols.


Abstract

Phenols are common precursors and core structures of a variety of industrial chemicals ranging from pharmaceuticals to polymers. However, the synthesis of site‐specifically substituted phenols is challenging, and thus the development of new methods for this purpose would be highly desirable. Reported here is a protocol for palladium‐catalyzed ortho‐selective alkylation reactions of phenols with primary alcohols by a dearomatization‐rearomatization strategy, with water as the sole by‐product. Various substituted phenols and primary alcohols were compatible with the standard reaction conditions. The detailed mechanism of this transformation was also investigated.

12 Feb 07:52

Three‐Component Alkene Difunctionalization by Direct and Selective Activation of Aliphatic C−H Bonds

by Sheng Xu, Herong Chen, Zhijun Zhou, Wangqing Kong
Three‐Component Alkene Difunctionalization by Direct and Selective Activation of Aliphatic C−H Bonds

A photocatalytic three‐component alkene difunctionalization method for the direct and selective activation of aliphatic C−H bonds is developed. The significant advantages of this strategy are that the most abundant hydrocarbons are used as feedstocks, and various highly functionalized tertiary, secondary and primary C(sp3)‐hybrid centers can be easily installed. The practicability of this strategy is demonstrated in the selective late‐stage functionalization of natural products and the concise synthesis of pharmaceutically relevant molecules including Piragliatin.


Abstract

Catalytic alkene difunctionalization is a powerful strategy for the rapid assembly of complex molecules and has wide range of applications in synthetic chemistry. Despite significant progress, a compelling challenge that still needs to be solved is the installation of highly functionalized C(sp3)‐hybridized centers without requiring pre‐activated substrates. We herein report that inexpensive and easy‐to‐synthesize decatungstate photo‐HAT, in combination with nickel catalysis, provides a versatile platform for three‐component alkene difunctionalization through direct and selective activation of aliphatic C−H bonds. Compared with previous studies, the significant advantages of this strategy are that the most abundant hydrocarbons are used as feedstocks, and various highly functionalized tertiary, secondary, and primary C(sp3)‐hybrid centers can be easily installed. The practicability of this strategy is demonstrated in the selective late‐stage functionalization of natural products and the concise synthesis of pharmaceutically relevant molecules including Piragliatin.