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Polymorphism, Weak Interactions and Phase Transitions in Chalcogen-Phosphorus Heterocycles.

ABSTRACT: A series of P-E-containing heterocycles (E=chalcogen) with aromatic backbones were synthesised and characterised by single-crystal and powder XRD, microanalysis and mass spectrometry. Solution- and solid-state 31 P and 77 Se NMR spectroscopy revealed significant differences between the NMR parameters in solution and in the solid state, related to conformational changes in the molecules. Many compounds were shown to exhibit a number of different polymorphic structures (identified by single-crystal XRD), although the bulk material studied by solid-state NMR spectroscopy often contained just one major polymorph. For the unoxidised heterocycles, the presence of weak intermolecular J couplings was also investigated by DFT calculations.

SUBMITTER: Camacho PS

PROVIDER: S-EPMC6099295 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Polymorphism, Weak Interactions and Phase Transitions in Chalcogen-Phosphorus Heterocycles.

Camacho Paula Sanz PS Stanford Martin W MW McKay David D McKay David D Dawson Daniel M DM Athukorala Arachchige Kasun S KS Cordes David B DB Slawin Alexandra M Z AMZ Woollins J Derek JD Ashbrook Sharon E SE

Chemistry (Weinheim an der Bergstrasse, Germany) 20180628 43

A series of P-E-containing heterocycles (E=chalcogen) with aromatic backbones were synthesised and characterised by single-crystal and powder XRD, microanalysis and mass spectrometry. Solution- and solid-state 31 P and 77 Se NMR spectroscopy revealed significant differences between the NMR parameters in solution and in the solid state, related to conformational changes in the molecules. Many compounds were shown to exhibit a number of different polymorphic structures (ident ...[more]

PMID: 29791041

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