96920-93-3Relevant academic research and scientific papers
NOUVELLE METHODE DE PREPARATION DE CETONES, ESTER ET NITRILE BENZYLIQUES α-FLUORES OU α,α-DIFLUORES
Laurent, E.,Marquet, B.,Tardivel, R.,Thiebault, H.
, p. 2359 - 2362 (1987)
By anodic oxidation in CH3CN/Et3N, 3HF benzylic ketones, ester and nitrile yield specifically corresponding monofluoro or difluoro compounds.The reaction proceeds through an α-carbonyl or an α-cyano carbocation.
Synthesis of Chiral Tertiary α,α-Difluoromethyl Carbinols by Cu-Catalyzed Asymmetric Propargylation
Ding, Kuiling,Guo, Peihua,Wang, Xiaoming,Wang, Zheng,Zhang, Rui
supporting information, (2019/11/28)
Chiral α,α-difluoromethyl carbinols are recurring structural motifs in many therapeutic agents. Despite the indubitable interest in the catalytic asymmetric synthesis of such compounds, this research field still remains largely underexplored. Herein, an efficient approach to a range of chiral homopropargylic α,α-difluoromethyl carbinols has been developed, through a Cu-catalyzed enantioselective propargylation of α,α-difluoroketones with (pinacolato)allenylboron. In the presence of a cuprous complex, generated in situ from CuCl and a spiroketal-based diphosphine (SKP) ligand, a variety of aryl-, heteroaryl-, alkyl-, alkynyl, alkenyl, or benzyloxycarbonyl-substituted α,α-difluoromethyl carbinols were obtained in 75–99 % yields with 84–98 % ee values. The catalytic system was further investigated using a combined dynamic NMR spectroscopic, X-ray crystallographic, and non-linear effect studies. The origin of the enantioselectivity was rationalized based on DFT calculations. Finally, several efficient transformations were showcased to highlight the utilities of the protocol in synthesis of complex compounds bearing an α,α-difluoromethyl carbinol moiety.
MONO ET DIFLUORATION ELECTROCHIMIQUES DE GROUPES BENZYLIQUES
Laurent, Eliane,Marquet, Bernard,Tardivel, Robert
, p. 4431 - 4444 (2007/10/02)
Anodic oxidation of benzylic compounds 1 using CH3CN as a solvent and Et3N,3HF as a fluorinating reagent allowed to introduce a fluorine atom in α position of electron withdrawing group via carbocation 1+ (ECBECN mechanism).Whatever the E group, monofluorides 2 are obtained in good yields from paramethoxy derivatives 1 (R=p-OCH3).In this case, by raising the potential of working electrode after the monofluorination step, gem difluorides 3 can be directly prepared from 1.When the substituent of the phenyl ring is different of a methoxy group, a mixture of fluoride 2 and acetamide 4 is generally obtained and the ratio of these two compounds is related to cation stability.
