S=o…s=o Interactions as a Driving Force for Low-Temperature Conformational Rearrangement of Stable H-Bonding {S(O)-Ch₂-Ch₂-OH···}₂ Synthon in two Modifications of Diastereomeric Pinanyl Sulfoxides Co-Crystal

GRAPHICAL ABSTRACT

For the triclinic and monoclinic modifications of diastereomeric pinanyl sulfoxides co-crystal, remarkable alterations in unit cell parameters by transition from 293 to 150 К were ascertained. Such alterations are accompanied by conformational restructuring of a stable hydrogen-bonded synthon from an “unfolded” to a “folded” form. The driving force of this restructuring is the tendency to form S=O…S=O interactions, which show up

in the low-temperature phases of both polymorphs. These are well-supported by the methods of quantum chemistry (DFT, B97-D/6-31G(d,p), AIM All).

Keywords:

• β-Hydroxy sulfoxide
• (–)-β-pinene
• “racemic compound-like” crystallization
• hydrogen-bonded cyclic dimers
• polymorphic modifications
• low-temperature X-ray structural analysis