126893-72-9Relevant academic research and scientific papers
Catalytic Enantioselective Synthesis of Highly Functionalized Difluoromethylated Cyclopropanes
Bos, Maxence,Huang, Wei-Sheng,Poisson, Thomas,Pannecoucke, Xavier,Charette, André B.,Jubault, Philippe
, p. 13319 - 13323 (2017/10/17)
The first catalytic asymmetric synthesis of highly functionalized difluoromethylated cyclopropanes is described. The method, based on a rhodium-catalyzed cyclopropanation of difluoromethylated olefins, gives access to a broad range of cyclopropanes bearing ester, ketone, or nitro functional groups. By using Rh2((S)-BTPCP)4 as a catalyst, the corresponding products were obtained in high yields and high diastereo- and enantioselectivities (up 20:1 d.r. and 99 % ee). This methodology allowed preparation of enantioenriched difluoromethylcyclopropanes for the first time.
Asymmetric Rh(II)-catalyzed cyclopropanation of alkenes with diacceptor diazo compounds: P -methoxyphenyl ketone as a general stereoselectivity controlling group
Lindsay, Vincent N. G.,Nicolas, Cyril,Charette, Andre B.
supporting information; experimental part, p. 8972 - 8981 (2011/08/04)
Different diacceptor diazo compounds bearing an α-PMP-ketone group were found to be effective carbene precursors for the highly stereoselective Rh2(S-TCPTTL)4-catalyzed cyclopropanation of alkenes (EWG = NO2, CN, CO2Me). The resulting products were readily transformed into a variety of biologically relevant enantiopure molecules, such as cyclopropane α- and β-amino acid derivatives. Different mechanistic studies carried out led to a rationale for the high diastereo- and enantioselectivity obtained, where the PMP-ketone moiety was found to play a critical role in the stereoinduction process. Additionally, the use of catalytic amounts of achiral Lewis bases to influence the enantioinduction of the reactions developed is documented.
ELECTROPHILIC SUBSTITUTION OF HYDROGEN IN DIAZOACETONITRILE
Morzherin, Yu. Yu.,Kolobov, M. Yu.,Shafran, Yu. M.,Bakulev, V. A.
, p. 1454 - 1456 (2007/10/02)
2-Carbonyl-substituted diazoacetonitriles were obtained by the reaction of diazoacetonitile with carboxylic acid chlorides and isocyanates.The acyl derivatives of diazoacetonitriles were identified in the form of the corresponding triphenylphosphazines.The carbamoylation products undergo cyclization to 1-substituted 4-cyano-5-hydroxy-1,2,3-triazoles in the course of the reaction.
