Diastereoselective reactions between oxazolidines and organolithiumreagents afford β-amino alcohols having chiral vinyl and alkynylsilane moieties. A meaningful change of regioselectivity, from the α- to the γ-position, occurred when these reactions were performed in the presence of titanium isopropoxide, since allyl and allenylsilane derivatives were thus produced.
Amino alcohols derived from phenylglycinol and having vinyl-, alkynyl- or allenylsilane moieties were transformed in the corresponding primary amines in two steps: oxidative cleavage of phenylglycinol and transimination with phenylhydrazine. This methodology gave general access to enantiomerically enriched amines without loss of enantioselectivity. (C) 2004 Elsevier Ltd. All rights reserved.