Cyclization of Suitably Substituted Polyols

The chemistry presented in the previous two sections focussed on the formation of hydroxyolefins followed by cyclization to the desired C-glycosides. The latter steps in the examples shown rely largely upon the cyclization of protected polyols. In this section, cyclization methods including ether formations, ketal formations and halide displacements are presented. 

SCHEME 7.97 Divinyl zinc additions and mercury cyclizations. 

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