A highly chemo- and stereo-selective cleavage of acetals derived from (−)(2R,4R)-2,4-pentanediol with organoaluminum and organotitanium reagents has been demonstrated. The reactions proceed under mild conditions with excellent yields and high chemoselectivities to give, after removal of the auxiliary, chiral alcohols of high enantiomeric purities.
Nucleophilic cleavages of acetals using organotitanium reagents. A new synthesis of chiral alcohols
作者:Atsunori Mori、Keiji Maruoka、Hisashi Yamamoto
DOI:10.1016/s0040-4039(01)81455-6
日期:1984.1
A highlychemo- and stereoselective cleavage of acetals derived from (−)-(2R,4R)-2,4-pentanediol with organotitanium reagents has been demonstrated. The reaction proceeds under mild conditions in excellent yield and high chemoselectivity to give, after removal of auxiliary, the chiral alcohols of high enantiopurities. In addition, complexation of chiral acetals and TiCl4 followed by treatment with
Asymmetric synthesis via chiral acetal templates. 8. Reactions with organometallic reagents
作者:Stephen D. Lindell、John D. Elliott、William S. Johnson
DOI:10.1016/0040-4039(84)80037-4
日期:——
The titanium tetrachloride catalyzed coupling of organometallic reagents with chiralacetals 1 is shown to provide a convenient route for the preparation of a variety of chiral alcohols 4 of high optical purity.