Tryst with a molecular and supramolecular oddity: an anti-Fürst–Plattner epoxide opening product as a designer additive for accessing an elusive polymorph

Abstract

Additive induced polymorphism of a conformationally locked tetraacetate 3 in presence of its diastereomer 4 is described. The ester 3 was specially crafted on a trans-decalin backbone to relegate the O–H⋯O H-bond donors to the molecular interior and have the peripheral H-bond acceptors in 1,3-syndiaxial relationship. The supramolecular assembly of 3 was destined to evolve along two mutually exclusive pathways, namely one, which employs intermolecular O–H⋯O H-bonds ( pathway 1) and the other that sacrifices these for intramolecular O–H⋯O H-bonds and settles for a crystal packing dictated by weak intermolecular interactions alone ( pathway 2). Exploiting the similarity between the self-assemblies of 4 and the two recently reported dimorphs of 3, the ester 3 has been stimulated to follow the elusive non-hierarchical pathway 2 through preferential inhibition of pathway 1. Interestingly, the inhibitor 4 was obtained serendipitously en route 3 via an apparent breakdown of Fürst–Plattner rule.