37934-98-8Relevant academic research and scientific papers
Efficient partial hydrogenation of trichloromethyl to gem-dichloromethyl groups in platinum on carbon-catalyzed system
Sawama, Yoshinari,Imanishi, Takahiro,Nakatani, Ryosuke,Fujiwara, Yuta,Monguchi, Yasunari,Sajiki, Hironao
supporting information, p. 4540 - 4546 (2014/06/10)
While gem-dichloromethyl groups can be directly synthesized by the mono-dechlorination of the corresponding trichloromethyl groups, the suppression control of the over-reduction to form chloromethyl or methyl functionalities is quite difficult. We have established the efficient and widely applicable mono-dechlorination method of the trichloromethyl groups to form the corresponding gem-dichloromethyl groups using platinum on carbon in dimethylacetamide as a specific solvent at 25 °C under a hydrogen atmosphere. The mono-dechlorination of the α,α,α- trichloromethylcarbonyl groups smoothly proceeded by the use of platinum on carbon as a catalyst in a highly chemoselective manner, while the efficient mono-dechlorination of the alkyl- and aryl-trichloromethyl groups required the combined use of Bu3SnH.
Platinum on carbon-catalyzed precise reduction control of trichloromethyl to Geminal-dichloromethyl groups
Imanishi, Takahiro,Fujiwara, Yuta,Sawama, Yoshinari,Monguchi, Yasunari,Sajiki, Hironao
supporting information; experimental part, p. 771 - 776 (2012/06/30)
Geminal-dichloromethyl derivatives could be efficiently synthesized by the highly chemoselective platinum on carbon-catalyzed mono-dechlorination of trichloromethyl substrates in dimethylacetamide (DMA) as a specific solvent at 25 °C under a hydrogen atmosphere. Copyright
Effect of ortho substituents on carbonyl carbon 13C NMR chemical shifts in substituted phenyl benzoates
Nummert, Vilve,Piirsalu, Mare,Maeemets, Vahur,Vahur, Signe,Koppel, Ilmar A.
experimental part, p. 1155 - 1165 (2010/07/13)
13C NMR spectra of 37 ortho-, meta-, and para-substituted phenyl benzoates, containing substituents in benzoyl and phenyl moiety, 4 ortho-substituted methyl and 5 ethyl benzoates as well as 9 R-substituted alkyl benzoates have been recorded. The influence of the ortho substituents on the carbonyl carbon 13C NMR chemical shift, δCO, was found to be described by a linear multiple regression equation containing the inductive, σI, resonance, σRo, and steric, EsB, or ν substituent constants. For all the ortho-substituted esters containing substituents in the acyl part as well as the phenyl part, the substituent-induced reverse inductive effect (ρIR > 0), and the negative steric effect (δorthosB were observed. In the case of ortho substituents in the phenyl part, the resonance effect was negligible. Due to inductive effect, the ortho electron-withdrawing substituents showed an upfield shift or shielding of the carbonyl carbon, while the electron-donating substituents had an opposite effect. Because of the sterical consequences, ortho substituents revealed a deshielding effect on the 13C NMR chemical shift of the carbonyl carbon. For all the meta- and para-substituted esters, the reverse substituent-induced inductive and resonance effects (ρIR4NBr and 2.25M Bu4NBr, and the IR frequencies, νCO, for the ortho-, meta-, and para-substituted phenyl benzoates and alkyl benzoates were correlated nicely with the corresponding 13C NMR substituent chemical shifts, ΔδCO. Copyright
Copper(I)-promoted dechlorinative Surzur-Tanner rearrangement of 2,2,2-trichloroethyl carboxylates
Ram, Ram N.,Meher, Nabin Kumar
, p. 145 - 147 (2007/10/03)
(Matrix presented) 2,2,2-Trichloroethyl carboxylates undergo highly efficient dechlorinative Surzur-Tanner rearrangement with 2 equiv of a 1:1 molar mixture of CuCl and bpy in boiling DCE to give 1-chloroethenyl carboxylates in which copper appears to play an important role, probably by coordinating the initial radical or as a Lewis acid catalyst.
