Synthesis of a Tetranuclear Organooxotin Cage by Debenzylation Reactions: X-ray Crystal Structure of [(PhCH₂)₂Sn₂O(O₂P(OH)-<i>t</i>-Bu)₄]₂

Abstract

The reactions of (PhCH2)2SnCl2, (PhCH2)2SnO·H2O, and (PhCH2)3SnCl with 2 equiv of t-BuP(O)(OH)2 afford the tetranuclear organooxotin cage [(PhCH2)2Sn2O(O2P(OH)-t-Bu)4]2 (4) in good yields. The formation of the half-cage intermediate [(PhCH2)2Sn2O(O2P(OH)-t-Bu)4] (4a) en route to 4 has been detected by 119Sn and 31P NMR. The molecular structure of compound 4 as determined by single-crystal X-ray analysis shows a tetranuclear cage structure containing two Sn−O−Sn motifs connected by bridging [t-BuP(OH)(O)2]- ligands. The solid-state structure of 4 is retained in solution.