Asymmetric syntheses of new functionalized beta-amino alcohols via diastereoselective addition of organometallic reagents onto oxazolidines.
Diastereoselective reactions between (S)-phenylglycinol-derived oxazolidines and two unsaturated organolithium reagents afforded chiral beta-amino alcohols having vinyl and alkynylsilane moieties. When the same reactions were performed in the presence of titanium isopropoxide, a dramatic change of regioselectivity was observed, from the alpha- to the gamma-position, thus producing beta-amino alcohols with allyl or allenylsilane functions. A rationalization of the observed diastereoselectivity was suggested for each case.
Agami
Claude
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Laboratoire de Synthèse Asymétrique (UMR CNRS 7611), Case courrier 47, Université Pierre et Marie Curie, 4 place Jussieu, 75005 Paris, France.
Comesse
Sébastien
S
Kadouri-Puchot
Catherine
C