Novel bis(β-diketonato)diorganotin(IV) derivatives containing bulky 4-acyl-5-pyrazolonato ligands: Influence of the steric hindrance of the acyl moiety on the solid state structures of tin complexes and their behaviour in solution

F. Caruso, C. Di Nicola, J.V. Hanna, F. Marchetti, C. Pettinari, R. Pettinari, M. Rossi, G.J. Rees, Brian Skelton, Allan White

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

New (Q)(2)SnR2 derivatives (HQ in general; in detail: HQ(CHPh2) = 4-diphenylacetyl-3-methyl-1-phenyl-5-pyrazolone; HQ(Bn) = 3-methyl-1-phenyl-4-phenylacetyl-5-pyrazolone; HQ(naph) = 3-methyl-4-naphthoyl-1-phenyl-5-pyrazolone; R = CH3, C2H5, C6H11, n- and t-C4H9, C6H5,) have been synthesised and characterised by analytical and spectral techniques. Variable temperature NMR studies of (Q(CHPh2))(2)SnR2 derivatives (R = CH3 and C2H5) in chlorohydrocarbon solvents indicate a fluxional behaviour, with rapid interconversion between six- and five-coordinate species, the latter containing a bidentate acylpyrazolonate and a monodentate one. The X-ray crystal structures of the diorganotin(IV) derivatives (Q(CHPh2))(2)SnMe2, (Q(CHPh2))(2)SnEt2, (Q(Bn))(2)SnMe2 and (Q(naph))(2)SnBu2n, inclusive of a representative of each Q(x) family, show the metal centres in a skewed trans octahedral configuration. The 4-acyl moiety of the beta-diketonate donor exerts a steric effect which is correlated to structural behaviour in the solid and solution state. A solid state Sn-119 CPMAS NMR study of the (Q(Bn))(2)SnR2 (R = CH3, C2H5, t-C4H9 and C6H5) complexes shows a marked deshielding effect and upfield movement of the 119Sn isotropic chemical shift (delta(iso)) through this series. The Sn-119 chemical shift spans (Omega) are the largest reported for directly oxo-coordinated Sn(IV) systems, although the markedly reduced Omega value for the (Q(Bn))(2)SnPh2 complex may be indicative of a cis octahedral coordination, in contrast to the trans octahedral coordination characterising the other complexes of this suite. (C) 2010 Elsevier B.V. All rights reserved.
Original languageEnglish
Pages (from-to)73-84
JournalInorganica Chimica Acta
Volume367
DOIs
Publication statusPublished - 2011

Fingerprint Dive into the research topics of 'Novel bis(β-diketonato)diorganotin(IV) derivatives containing bulky 4-acyl-5-pyrazolonato ligands: Influence of the steric hindrance of the acyl moiety on the solid state structures of tin complexes and their behaviour in solution'. Together they form a unique fingerprint.

Cite this