Polymorphs of 1,1-bis(4-hydroxyphenyl) cyclohexane and multiple Z ' crystal structures by melt and sublimation crystallization

摘要

Close packing conflict in a metastable polymorph of the pure title host (Z' = 2, melt crystal 1m) is resolved in the stable form (Z' = 1, sublimed crystal 1s) as O-H center dot center dot center dot O hydrogen bond changes to O-H center dot center dot center dot pi interaction. Melt crystallization and sublimation show a greater percentage of high Z' structures in CSD statistics.