Cerium(III) chloride promoted opening of [3.2.1] oxabicycles with methyllithium

Article abstract of DOI:10.1016/S0040-4039(99)01764-5

Previously reported 1-cyclohexylhydroxymethyl-2,4-dimethyl-8-oxabicyclo [3.2.1]octen-3-ols 2 can be ring opened to produce substituted cycloheptenes 3 in a highly regio- and stereoselective reaction using MeLi in the presence of CeCl₃. These functionalized cycloheptenes contain an array of five contiguous stereocenters which provide access to polypropionate fragments with 1,3,5-syn,syn methyl groups.