102-17-0Relevant articles and documents
Palladium-catalyzed carbonylation of benzylic ammonium salts to amides and esters: Via C-N bond activation
Yu, Weijie,Yang, Shuwu,Xiong, Fei,Fan, Tianxiang,Feng, Yan,Huang, Yuanyuan,Fu, Junkai,Wang, Tao
supporting information, p. 3099 - 3103 (2018/05/22)
An efficient palladium-catalyzed carbonylation reaction of readily available quaternary ammonium salts with CO is reported for the first time to afford arylacetamides and arylacetic acid esters via benzylic C-N bond cleavage. This protocol features mild reaction conditions under atmospheric pressure of CO, a redox-neutral process without an additional oxidant, and a broad substrate scope for various kinds of amines, alcohols and phenols.
Benzyloxy(4-substituted benzyloxy)carbenes. Generation from oxadiazolines and fragmentation to radical pairs in solution
Merkley,Warkentin
, p. 942 - 949 (2007/10/03)
Thermolysis of 2,2-dibenzyloxy-5,5-dimethyl-Δ3-1,3,4-oxadiazoline in benzene at 110°C leads to dibenzyloxycarbene. The carbene was trapped with tert-butyl alcohol to afford dibenzyl-tert-butyl orthoformate. In the absence of a trapping agent for the carbene, it fragmented to benzyloxycarbonyl and benzyl radicals, as shown by trapping the latter with TEMPO. In the absence of both TEMPO and tert-butyl alcohol, the radicals were partitioned between coupling to benzyl phenylacetate and decarboxylation, with subsequent formation of bibenzyl. The preferred sense of fragmentation of the analogous carbenes from benzyloxy-(p-substituted-benzyloxy)carbenes was determined by comparing the yields of the two possible esters, ArCH2O(CO)CH2Ph and PhCH2O(CO)CH2Ar. It was found that an electron-withdrawing group in the para position favoured fragmentation to the benzylic radical containing that group. A Hammett plot of the data gave a best fit with σ- substituent constants (r = 0.994, ρ((PhH, 110°C) = 0.7)) suggesting that the fragmentation involves charge separation in the sense that increases electron density on the group that is becoming a benzylic radical and decreases electron density on the carbonyl group that is becoming the benzyloxycarbonyl radical.
Synthesis of substituted benzyl esters
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, (2008/06/13)
A process for preparing certain substituted benzyl esters of phenylacetic acids by esterification in a solvent in which the salt of the acid is insoluble, and in the presence of a phase transfer catalyst.
