Synthese et etude par RMN 119Sn de nouveaux composes benzyliques organostanniques

alpha,alpha'-m-Xylenediylbis(indium dichloride). A Novel Bifunctional Lewis Acid

Reaction of the di-Grignard compound 1,3-(ClMgCH(2))(2)C(6)H(4) with HgCl(2) yields 1,3-(ClHgCH(2))(2)C(6)H(4) (1), which crystallizes in the orthorhombic space group P2(1)2(1)2(1) with a = 8.494(1), b = 10.859(1), and c = 10.906(1) Å, V = 1005.9(2) Å(3), and Z = 4 (R values: R1 = 0.0354, wR2 = 0.0942). Treatment of 1 with InCl results in a transmetalation reaction and affords the tetrakis(tetrahydrofuran) adduct of 1,3-(Cl(2)InCH(2))(2)C(6)H(4) (2), which crystallizes in the monoclinic space group I2/a with a = 15.230(1), b = 13.125(1), and c = 15.299(1) Å, beta = 92.14(1) degrees, V = 3056.0(4) Å(3), and Z = 4 (R values: R1 = 0.0411, wR2 = 0.1003). As indicated by (199)Hg NMR spectroscopy, compound 1 does not form any stable anionic complexes in the presence of chlorides. In contrast, compound 2 readily complexes chloride anions. According to a VT (1)H NMR investigation, the species present in an equimolar mixture of 2 and Ph(4)PCl is the monoanionic complex [1-(Cl(3)InCH(2))-3-((THF)(2)Cl(2)InCH(2))C(6)H(4)](-) (3), whose structure is fluxional at room temperature. From this mixture, the salt [1,3-(Cl(3)InCH(2))(2)C(6)H(4)](2-)[Ph(4)P(+)](2) (4) can been isolated by precipitation. Compound 4 crystallizes in the orthorhombic space group P2(1)2(1)2(1) with a = 14.632(1), b = 17.080(1), and c = 21.384(1) Å, V = 5344.2(5) Å(3), and Z = 4 (R values: R1 = 0.0346, wR2 = 0.0649).