Synthesis and fluorine-mediated interactions in methanol-encapsulated solid state self-assembly of an isatin-thiazoline hybrid

Abstract

An exciting isatin-thiazoline hybrid molecule 2 having -CN-NC- linkage has been synthesized in 88% yield by the reaction of 5-fluoroisatin with N-(4-fluorophenyl)hydrazinecarbothioamide followed by condensation of the resultant isatin-thiosemicarbazone intermediate with p-chlorophenacyl bromide. The solid state self-assembly of this hybrid molecule was studied by X-ray crystallographic technique. A layered assembly composed of 1D-chains with methanol molecules encapsulated between every two chains is obtained, making a bi-chain sandwich like structure. The supramolecular forces involved in the stabilization of this structure are importantly fluorine-mediated interactions (C-H•••F, •••S and •••π) along with others i.e. N-H•••O, O-H•••O, C-H•••O, Cl•••π, C-H•••π and π•••π interactions. To the best of our knowledge, this is the first example of solid state fluorine-mediated C-H•••F, •••S and •••π interactions found in a family of isatin-based compounds.