Enantioselective acetalization of racemic 1,3-alkanediols with l-methone under kinetically controlled conditions
1992; Elsevier BV; Volume: 48; Issue: 40 Linguagem: Inglês
10.1016/s0040-4020(01)89438-2
ISSN1464-5416
AutoresToshiro Harada, Sachi Tanaka, Akira Oku,
Tópico(s)Synthetic Organic Chemistry Methods
ResumoRacemic 1,3-alkanediols (rac-1) undergo an enantioselective acetalization by treatment with l-methone enol trimethylsilyl ether (10) in the presence of trifluoromethanesulfonic acid (10 mol%) to give thermodynamically less stable spiroacetal 3 (derived from 1) in preference to spiroacetal 4 (derived from ent-1). The kinetically controlled acetalization is applied to a novel kinetic resolution of racemic 1,3-alkanediols: Optically active diols ent-1 of 55–95 % ee are obtained when the racemic diols are allowed to react with 1.5 equiv of enol silyl ether 10 under similar conditions.
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