1,3-Diphenylpropane-1,3-diamines XII [1]. A Novel Approach to Stereodefined Oximes and Oxime Ethers of Monothioketalized 1,3-Diketones and their Conversion to 3-Aminooximes
作者:Alexander Kaiser、Wolfgang Wiegrebe
DOI:10.1007/pl00013502
日期:1998.9
Mono-O,O- and mono-S,S-ketals of 1,3-diphenylpropane-1,3-diones react with hydroxylamine hydrochloride and O-methylhydroxylamine hydrochloride affording mixtures of (E/Z) isomers which are hard to separate or an even unseparable. Isomerically pure oximes and O-methyloximes, however, are obtained either from 2-lithiated 1,3-dithianes and alpha-halogeno-oximes and alpha-halogeno-oxime ethers, resp., or from lithiated oxime ethers and dithienium salts. Reduction, acetylation, hydrolysis of the ketal increment, and oximation afford 3-amino-oximes which are precursors of 1,3-diphenylpropane-1,3-diamines.