Synthesis and structures of three, four, and six-coordinate monomeric tin(II) and tin(IV) compounds containing eta(2)-ketiminate ligands

摘要

A series of Sn(II) and Sn(IV) compounds containing ketiminate ligands were synthesized. Reactions of SnCl2 with 1 or 2 equiv. Li[OCMeCHCMeNAr] (where Ar = 2,6-diisopropylphenyl) generate [OCMeCHCMeNAr]SnCl (1) and [OCMeCHCMeNAr](2)Sn (2) in moderate yield, respectively. Similarly, reacting SnCl4 with 2 equiv. Li[OCMeCHCMeNAr] yields a six-coordinated [OCMeCHCMeNAr](2)SnCl2 (3). Divalent tin compound 2 can be oxidized with I-2 in diethyl ether to generate tetravalent tin compound [OCMeCHCMeNAr](2)SnI2 (4) in moderate yield. Compounds 1-4 have been characterized by H-1 and C-13 NMR spectroscopy and have been analyzed by X-ray crystallography. Theoretical calculation found that the bonding of ketiminate ligands and tin atom in compound 2 has a strong ionic character.