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Mechanochemical synthesis of N-salicylidene-aniline: thermosalient effect of polymorphic crystals.

ABSTRACT: Polymorphs of the dichloro derivative of N-salicylideneaniline exhibit mechanical responses such as jumping (Forms I and III) and exploding (Form II) in its three polymorphs. The molecules are connected via the amide N-H?O dimer synthon and C-Cl?O halogen bond in the three crystal structures. A fourth high-temperature Form IV was confirmed by variable-temperature single-crystal X-ray diffraction at 180°C. The behaviour of jumping exhibited by the polymorphic crystals of Forms I and III is due to the layered sheet morphology and the transmission of thermal stress in a single direction, compared with the corrugated sheet structure of Form II such that heat dissipation is more isotropic causing blasting. The role of weak C-Cl?O interactions in the thermal response of molecular crystals is discussed.

SUBMITTER: Mittapalli S

PROVIDER: S-EPMC5414398 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Mechanochemical synthesis of N-salicylidene-aniline: thermosalient effect of polymorphic crystals.

Mittapalli Sudhir S Sravanakumar Perumalla D D Nangia Ashwini A

IUCrJ 20170327 Pt 3

Polymorphs of the dichloro derivative of N-salicylideneaniline exhibit mechanical responses such as jumping (Forms I and III) and exploding (Form II) in its three polymorphs. The molecules are connected via the amide N-H⋯O dimer synthon and C-Cl⋯O halogen bond in the three crystal structures. A fourth high-temperature Form IV was confirmed by variable-temperature single-crystal X-ray diffraction at 180°C. The behaviour of jumping exhibited by the polymorphic crystals of Forms I and ...[more]

PMID: 28512571

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