TRIORGANOTIN(IV) DERIVATIVES OF SEVERAL 4-ACYL-5-PYRAZOLONATO LIGANDS - SYNTHESIS, SPECTROSCOPIC CHARACTERIZATION AND BEHAVIOR IN SOLUTION CRYSTAL STRUCTURE OF AQUOTRIMETHYL(4-P-METHOXYBENZOYL-1-PHENYL-3-METHYL-PYRAZOLON-5-ATO) TIN(IV)

摘要

New triorganotin(IV) derivatives [(Q)SnR(3) . x(H2O)] (x=0, R=Ph; x=1, R=Me and (n)Bu) (in general QH=1-R'-3-methyl-4-R '' (C=O)-pyrazol-5-one; in detail Q'H:R'=C6H5, R ''=C6H5;Q(A)H:R'=C6H5, R ''=p-CH3O-C6H4; Q(N)H:R'=C6H5, R ''=p-NO2-C6H4; Q(Br)H:R'=C6H5, R ''=p-Br-C6H4; Q '' H:R'=C6H5, R ''=CH3; QCl(3)H:R'=C6H5, R ''=CCl3; Q(F)H: R'=C6H5, R ''=CF3; Q(M)H:R'= CH3, R ''=C6H5; Q(D)H:R'=CH3, R ''=CH3) have been synthesized and characterized by analysis and spectral (IR and H-1, C-13 and Sn-119 NMR) data, The (Q)SnPh(3) derivatives are five-coordinated in the solid state, with a likely skewed cis-trigonal bipyramidal (cis-TBP) geometry around the tin center and the ligand(Q)(-) acting in the bidentate form. In [(Q)SnR(3) .(H2O)] derivatives (R=(n)Bu or Me) a coordination site is occupied by water, with the ligand (Q)(-) coordinating in a monodentate fashion. The crystal structure of [(QA)SnMe(3) .(H2O)] has been determined: the tin atom is found in a distorted TBP environment, with the methyls in the equatorial positions. Two of the Sn-C bond lengths are normal (2.11(1) and 2.08(2) Angstrom) whereas the third is longer (2.18(2) Angstrom); the ligand binds the metal atom through one carbonyl oxygen in the apical position (Sn-O=2.10(1) Angstrom). The bond length between H2O and Sn is longer (2.41(2) Angstrom), and the O-Sn-O angle is 174.9(5)degrees. H atoms of water are involved in an intermolecular H-bond network with uncoordinated carbonyl and the pyridinic N atom of the ligand. In chloroform solution the [(Q)SnR(3) .(H2O)] derivatives (R=Me or (n)Bu) lost the molecule of water and adopt a tetrahedral arrangement, They also give rise to a slow disproportionation, yielding SnR(4) and [(Q)(2)SnR(2)] derivatives. [References: 73]