Electronic Characteristics of Sn-Hal Bonds in Hexa- and Pentacoordinate Tin(IV) Adducts

Experimental da ta on ligand effects in the chemistry of main group elements are less extensive than in the coordination chemistry of transition elements. The relation between the donor properties of ligands L and the halogen ligands in tin(IV) complexes of the type SnHal 4 L 2 being often uncertain, we performed a systematic N Q R study of tin(IV) complexes of the type Alk„SnHal4_„L2 , where one or two acido ligands were substituted by er-donor groups (R) which notably exceeded the halogen ligands in donating power [1-4]. Among various theoretical approaches developed to predict the effects of substituents on main group element complexes, the one developed by Musher [5] and applied by Shustorovich et al. [6] to the com-