Bisisocyanide complexes of Zn(II) halides: Synthesis, structure, and application in the catalysis of isocyanides reaction with secondary amines

Abstract

Isocyanide zinc complexes [ZnX₂(CNR)₂] (X = Cl, Br, I; R = Xyl, Cy, Bu^t) have been prepared via the interaction of the corresponding zinc halides ZnX₂ and isocyanide CNR in toluene at 100°C (yield 64–77%) and characterized by the data of elemental analysis, mass spectrometry, IR and NMR spectroscopy, and X-ray diffraction analysis. The zinc complexes [ZnBr₂(CNR)₂] (R = Xyl, Сy) have been used as catalysts for the synthesis of formamidines R¹N=CHNR₂² [R¹ = Xyl, Сy; R₂² = Et₂, (CH₂)₄, (CH₂CH₂)₂NMe, Me + CH₂Ph] from isocyanides CNR¹ and secondary amines HNR₂² in bulk (yield 92–98%).