A method for the chromatographic resolution of tetrahydropyran-2-ones
作者:Philip Ashworth、Shiddappa L. Belagali、Sharon Casson、Anna Marczak、Philip Kocieński
DOI:10.1016/s0040-4020(01)80729-8
日期:1991.12
The spirocyclic ortholactones prepared from certain tetrahydropyran-2-ones (valerolactones) and (1R)-1-phenylpropan-1,3-diol are readily separable by flash chromatography on silica gel. Hydrolysis of the resolved ortholactones then provides the pure homochiral lactones.
A synthesis of the spiroacetal moiety of milbemycin β<sub>3</sub>
作者:Philip Kocienski、Stephen D. A. Street
DOI:10.1039/c39840000571
日期:——
Intramolecular reaction of an enol silylether with a dioxonium ion generated by treatment of the 1,5,7-trioxaspiro[5.5]undecane (5b) with BF3·Et2O was the key step in a synthesis of the 1,7-dioxaspiro[5.5]undecane moiety (2) of Milbemycin β3(1).