The distinctively singular self-assembly of a “molecular stair”: observation of a quadrilateral C–H⋯O hydrogen bonding cycle in the crystal structure of a tetracyclic oligo-tetrahydrofuran

Abstract

A comparative analysis of the C–H⋯O hydrogen bonded crystal structures of three structurally related ‘molecular stairs’ (anti-fused oligoannelated tetrahydrofurans) has led to the identification of a scarcely encountered quadrilateral C–H⋯O hydrogen bonding cycle, involving a pair of bifurcated H-bonds and two lactone carbonyl oxygens, in a chiral trigonal space group.