A general Pd-catalyzed α- and γ-benzylation of aldehydes for the formation of quaternary centers
作者:Ivan Franzoni、Laure Guénée、Clément Mazet
DOI:10.1039/c5ob00702j
日期:——
A palladium-catalyzed benzylation of α-branched aldehydes has been developed using benzyl methyl carbonates. The method gives access to congested quaternary centers in the vicinity of one of the most sensitive carbonyl functionalities and displays unprecedented generality with respect to both coupling partners. Evidence for the direct involvement of a Pd-η3-benzyl intermediate is provided. Extension
Light-induced synthesis of unsymmetrical organic carbonates from alcohols, methanol and CO<sub>2</sub> under ambient conditions
作者:Sandhya Saini、Nand Kishor Gour、Shafiur Rehman Khan、Ramesh Chandra Deka、Suman L Jain
DOI:10.1039/d1cc05833a
日期:——
The present work describes the first visible light-assisted, metal-free and organic base 1,1,3,3-tetramethyl guanidine (TMG) mediated synthesis of unsymmetrical methyl aryl/alkyl carbonates from the reaction of alcohols, methanol, and CO2 in high to excellent yields under atmospheric pressure and ambient temperature conditions.
目前的工作描述了第一个可见光辅助、无金属和有机碱 1,1,3,3-四甲基胍 (TMG) 介导的由醇、甲醇和 CO 2的反应合成的不对称甲基芳基/碳酸烷基酯在大气压和环境温度条件下以高到极好的收率。
Palladium-catalyzed Cross-coupling of Benzylic Carbonates with Organostannanes
作者:Masato Ohsumi、Ryoichi Kuwano
DOI:10.1246/cl.2008.796
日期:2008.7.5
The cross-coupling of benzylic carbonates with arylstannanes proceeded in the presence of [Pd(η3-C3H5)Cl]2–DPPPent catalyst, affording the desired diarylmethanes in good yield.
Substrate switchable Suzuki–Miyaura coupling for benzyl ester <i>vs.</i> benzyl halide
作者:Masato Ohsumi、Akitaka Ito、Nagatoshi Nishiwaki
DOI:10.1039/c8ra07841f
日期:——
developed to accomplish the substrate switchable Suzuki–Miyaura coupling of benzyl derivatives and arylboronic acid derivatives. Under conditions for esters, benzyl esters such as carbonates and acetates reacted with arylboronic acids to afford the corresponding diarylmethanes. However, the benzyl halides did not react under the same conditions. On the other hand, benzyl halides such as bromides and
A palladium‐catalyzed cross‐coupling reaction between C(sp) and C(sp3) centers was achieved in excellent yields via C–C bond cleavage and C–O bond cleavage. The method uses benzylic carbonates and also avoids the involvement of benzyl halides, making it more practical in organic synthesis.