A stereocontrolled access to vicinal difluoroalkanes
An expedient method for the prepn. of diastereomerically and, by extension, even enantiomerically pure vicinal difluoroalkanes is described. The two fluorine atoms are introduced in two consecutive steps: ring opening of an oxirane by addn. of hydrogen fluoride and subsequent treatment of the resulting hydroxy fluoride with diethylaminosulfur trifluorides. Thus, sep. treatment of (E)- and (Z)-RCH:CHR [R = (CH2)4Me] via epoxidn., HF addn, and fluorination, gave dl- or meso-RCHFCHFR, resp. [on SciFinder (R)]
1988
44
10
2875
2881
CAN 110:94451
23-3
Aliphatic Compounds
Inst. Chim. Org.,Univ. Lausanne,Lausanne,Switz.
Journal
written in English.
130888-52-7 Role: RCT (Reactant), RACT (Reactant or reagent) (fluorination of, with diethylaminosulfur trifluoride); 7782-41-4 Role: RCT (Reactant), RACT (Reactant or reagent) (fluorination, stereoselective, of alkenes via epoxidn., fluoride ring opening, and reaction with diethylaminosulfur trifluoride, vicinal difluoroalkanes from); 7206-17-9P (trans-6-Dodecene); 7206-29-3P (cis-6-Dodecene) Role: RCT (Reactant), SPN (Synthetic preparation), PREP (Preparation), RACT (Reactant or reagent) (prepn. and epoxidn. of, with monoperphthalic acid); 130876-18-5P Role: RCT (Reactant), SPN (Synthetic preparation), PREP (Preparation), RACT (Reactant or reagent) (prepn. and fluorination of); 92943-15-2P (cis-6,7-Epoxydodecane); 92943-16-3P Role: RCT (Reactant), SPN (Synthetic preparation), PREP (Preparation), RACT (Reactant or reagent) (prepn. and ring opening of, with hydrogen fluoride-triethylamine complex); 119105-44-1P; 119105-45-2P Role: SPN (Synthetic preparation), PREP (Preparation) (prepn. of); 4762-26-9 (Hexyl triphenylphosphonium bromide) Role: RCT (Reactant), RACT (Reactant or reagent) (stereoselective Wittig reaction of, with hexanal); 66-25-1 (Hexanal) Role: RCT (Reactant), RACT (Reactant or reagent) (stereoselective Wittig reaction of, with hexyltriphenylphosphonium bromide)
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