Back to the Coordination Modes of the Thiosemicarbazonate Chain: New Insights from Diorganolead(IV) and Lead(II) Derivatives of Isatin‐3‐thiosemicarbazone
作者:José S. Casas、Noelia Casanova、María S. García‐Tasende、Agustín Sánchez、José Sordo、Ángeles Touceda、Saulo Vázquez
DOI:10.1002/ejic.201000669
日期:2010.11
kinetically controlled O,N 2 ,S isomer formed first due to the rigidity of the ligand. If the compound remains in solution, slow partial evolution to the O,N 3 ,S isomer occurs. DFT calculations predict that [Pb(OAc)(N 3 -L 1 )] is slightly more stable than [Pb(OAc)(N 2 -L 1 )] both in the gas phase and in DMSO solution. The calculations also modelled structures for the two isomers close to those obtained
在赤道平面上具有顶端苯基和 O,N x ,S-配位的 L x- 和异双齿 AcO - 配体。在 [PbPh 2 (OAc)(N 2 -L 1 )]·MeOH·EtOH 中,(N 2 -L 1 ) - 配体与金属形成四元和六元螯合环,而在 PbPh 2 ( OAc)(N 3 -L 2 )]·H 2 O 由(N 3 -L 2 ) - 形成的两个螯合环是五元的。从同一溶液中分离出的 Pb II 复合物 [Pb(OAc)(N 2 -L 1 )] 和 [Pb(OAc)(N 3 -L 1 )] 是连接异构体。这些化合物具有相当不规则的立体化学,表明存在立体化学活性的孤电子对;在 [Pb(OAc)(N 2 -L 1 )] 中,(L 1 ) - 配体是 O,N 2 ,S-配位,在 [Pb(OAc)(N 3 -L 1 )] 中,该配体是 O, N 3 ,S-配位。通过 1 H 和 13 C NMR 光谱分析