名称:
The O,C,O-Coordinating Pincer-Type Ligand {2,6-[P(O)(OEt)2]2-4-t-Bu-C6H2}- in Organotin Chemistry. Halide Exchange, Cyclization, and Novel Coordination Mode
摘要:
eactions in solution of the hypercoordinated organotin chlorides {2,6-[P(O)(OEt)(2)](2)-4-tBu-C6H2}SnCl2X (X = Ph, Cl) with fluoride ions have been studied using temperature-dependent Sn-119 and P-31 NMR spectroscopy and electrospray mass spectrometry. The syntheses and molecular structures of the novel intramolecularly coordinated diorganotin difluoride {2,6-[P(O)(OEt)(2)](2)-4-t-Bu-C6H2}SnF2Ph .0.5H(2)O (1), the heterocyclic compound {[1(Sn),3(P)-PhClSnOP(O)(OEt)-5-t-Bu-7-P(O)(OEt)(2)]C6H2}(2) (3), and the monoorganotin difluoride hydroxide {{2,6-[P(O)(OEt)(2)](2)-4-t-Bu-C6H2}SnF2OH}(2) (6) are reported. In the crystal lattice, compound 1 forms an adduct composed of two tin moieties and a water molecule which are linked via F . . .H-O-H . . .F hydrogen bridges. The intramolecularly coordinated benzoxaphosphastannole derivative 3 is formed by intramolecular cyclization of {2,6-[P(O)(OEt)(2)](2)-4-t-Bu-C6H2}SnCl2Ph with elimination of ethyl chloride and dimerization. The organotin difluoride hydroxide derivative 6 is a dimer in the solid state as a result of intermolecular hydroxide bridges. Also present are intramolecular Sn-O-H . . .O=P hydrogen bonds. The configuration at tin is best described as a monocapped octahedron.