Synthese, Struktur und Reaktivität von Aminomethylpyridin- zinkdihalogeniden / Synthesis, Structure and Reactivity of Aminomethylpyridine Zinc Dihalides

Abstract

Zinc dichloride reacts with aminomethylpyridine (AMP) to the corresponding 1:1 adduct 1, whereas ZnBr2 forms an ionic 1:2 complex of the type [(AMP)2ZnBr]+ Br- 2, which loses one neutral coligand upon heating in Me-C (O)OEt to yield nearly insoluble (AM P)ZnBr2 3. The condensation reaction of these compounds with acetone yields propylideneaminomethylpyridine zinc dichloride (4) and dibromide (5), respectively. The reaction of ZnI2 with AMP and acetone gives propylideneaminomethylpyridine zinc dichloride (6) in quantitative yield. The structures of 3, 4, and 6 confirm the linear relationship between the Zn-N distance and the X-Zn-X angle in compounds of the type (L2)ZnX2 with L2 being a bidentate amino base, whereas short Zn-N bonds enforce small X-Zn-X angles. Compound 2 consists of separated ions in the solid state with a five coordinate zinc atom in a distorted trigonal bipyramidal coordination sphere