Tin(IV) and organotin(IV) derivatives of anionic 4-acyl-5-pyrazolonato ligands: synthesis, spectroscopic characterization (IR, far-IR, 119Sn mössbauer, 1H, 13C and 119Sn NMR) and behavior in solution crystal and molecular structure of trans-diphenylbis[1-phenyl-3-methyl-4-(4-bromobenzoyl) -pyrazolon-5-ato]tin(IV)

Abstract

Stable six-coordinate tin(IV) and organotin(IV) derivatives X 2SnQ 2 (X = Me, Ph, benzyl, cyclohexyl, Cl or tBu) (QH = 1-R'-3-methyl-4-R'(CO)-pyrazol-5-one in general; in detail Q'H: R' = C 6H 5, R' = C 6H 5 Q'H: R' = C 6H 5, R' = CH 3; Q AH: R' = C 6H 5 R' = p-CH 3O-C 6H 4; Q BrH: R' = C 6H 5 R' = p-Br-C 6H 4) have been synthesized and characterized by analysis and spectral (IR and far-IR, 1H, 13C and 119Sn NMR, 119Sn Mössbauer) data. Structural predictions were derived from 119Sn NMR parameters such as 1 J ( 119Sn- 13C) , 2 J ( 119Sn- 1H) and δ( 119Sn). The diffraction study of the complex [Ph 2Sn(Q Br) 2] shows the metal to be six-coordinate in a skewed trapezoidal bipyramidal geometry; Sn-O distances are 2.12(1) and 2.143(7) Å, and 2.223(8) and 2.26(1) Å and the Ph-Sn-Ph bond angle is 173.0(7)°.