REACTION OF ALDEHYDES AND KETONES WITH t-BUTYL BROMIDE-DIMETHYL SULPHOXIDE

Article abstract of DOI:10.1016/S0040-4020(01)88443-X

Reacting aldehydes and ketones with the "Bu^tBr-Me2SO" system produces the corresponding α-bromoderivatives 2.In the case of ketones, where more than one regioisomer is possible, bromination is obtained exclusively at the more highly substituted α-position.With slight modifications of the reaction conditions (addition of Me2S, Me2SO) it is possible to obtain "in situ" formation of either dimethyl(2-oxo-phenylalkyl)sulphonium salts 3 or of α-methylthioderivatives 4.Dimethyl(1-methyl-2-oxo-2-phenylethyl)sulphonium bromide (3h) during crystallization undergoes spontaneous resolution of the two enantiomers, as demonstrated by single crystal X-ray analysis and absolute configuration assignment.