39749-79-6Relevant articles and documents
Iodobenzene Dichloride in the Esterification and Amidation of Carboxylic Acids: In-Situ Synthesis of Ph3PCl2
Carle, Myriam S.,Shimokura, Grace K.,Murphy, Graham K.
, p. 3930 - 3933 (2016)
A novel, in-situ synthesis of dichlorotriphenylphosphorane (Ph3PCl2) is accomplished upon combining PPh3and the easily prepared hypervalent iodine reagent iodobenzene dichloride (PhICl2). The phosphorane is selectively generated in the presence of carboxylic acid or alcohol residues to rapidly produce acyl chlorides and alkyl chlorides in high yields. Addition of EtOH, PhOH, BnOH, Et2NH or CH2N2results in the direct synthesis of esters, amides and diazo ketones from carboxylic acids.
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.
Catalysed asymmetric protonation of simple linear keto-enolic species a route to chiral α-arylpropionic acids
Roy, Olivier,Riahi, Abdelkhalek,Henin, Francoise,Muzart, Jacques
, p. 3986 - 3994 (2007/10/03)
The reaction cascade consisting of deprotection/decarboxylation/asymmetric protonation of enolic species, starting from open-chain benzyl β-oxo esters, has been studied. When carried out in the presence of catalytic amounts of cinchonine, the reaction gave optically active α-aryl ketones with up to 75% ee. Enantio-enriched (S)-3-phenyl-2-butanone can be converted into 2-phenylpropionic acid without racemisation. Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002.
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.
