The synthesis of the o-phenylene-bridged ditin species o-C 6 H 4 (SnXMe 2 ) 2 (2, X ) Cl; 4, X ) F) and o-C 6 H 4 (SnCl 2 Me) 2 (3) is reported and the crystal structures of [o-C 6 H 4 (SnClMe 2 ) 2 ‚ Cl] -[(Ph 3 N) 2 P] + (5) and [o-C 6 H 4 (SnClMe 2 ) 2 ‚F] -[K‚C 20 H 24 O 6 ] + (7) are described. Variabletemperature 119 Sn and 19 F NMR studies indicate that 2 and 4 act as bidentate Lewis acids toward chloride and fluoride ions exclusively forming the stable anionic 1:1 complexes 5, 7, and [o-C 6 H 4 (SnFMe 2 ) 2 ‚F] -[Et 4 N] + ( 8). No formation of dianionic 1:2 adducts was observed even with excess of halide ions. The affinity of 2 toward fluoride is greater than toward chloride. Reaction of 2 with HMPA gives the neutral complex o-C 6 H 4 (SnClMe 2 ) 2 ‚(Me 2 N) 3 PO (10), the crystal structure of which is also described.

Insoluble diorganotin functionalized polymers of the type (P-H) 1-t (P-(CH 2 ) n SnBuX 2 ) t , with n ) 4, 6, X ) Ph, Cl, and t being the degree of functionalization, were synthesized from Amberlite XE-305, an insoluble polystyrene (P-H) cross-linked with divinylbenzene. The synthesis conditions used gave rise to functionalization degrees varying from 25% to 30%. The tin-functionalized polystyrenes were characterized by elemental analysis, IR, and Raman as well as solid-state 117 Sn and 13 C NMR spectroscopy. Methodological and chemical features related to the determination of the functionalization degree have been investigated in detail. The catalytic activity of the Amberlite-grafted tin functionalities in transesterification reactions was studied.

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Syntheses of a series of trinuclear tin compounds, (Ph2XSnCH2)2SnXPh (2, X = Ph; 6, X = F; 8, X = Cl) and (PhCl2SnCH2)2SnCl2 (10) and tetranuclear tin compounds (Ph2XSnCH2SnXPh)2CH2 (3, X = Ph; 7, X = F; 9, X = Cl) are reported, and the crystal structure of [(Ph2FSnCH2)2SnFPh·F]-[C12H24O6·K]+ (6b) is described. Variable temperature 119Sn and 19F NMR studies indicate that the structure observed for the anion in 6b in the solid state is retained in solution. There is no NMR evidence for the formation of 1:2 adducts with fluoride ion, although such species are identified in acetonitrile solutions from electrospray mass spectrometry (ESMS). 119Sn NMR spectral data indicate that reaction of trinuclear tin compound 8 with [(Ph3P)2N]+Cl- and HMPA results in formation of the 1:1 complexes [(Ph2ClSnCH2)2SnClPh·Cl]-[(Ph3P)2N]+ (8a) and (Ph2ClSnCH2)2SnClPh·[(CH3)2N]3PO (8b), respectively. In contrast, 19F and 119Sn NMR data show that the tetranuclear tin compound 7 reacts with fluoride ion to give a stable 1:2 adduct [(Ph2FSnCH2SnFPh)2CH2·2F]2-2[Bu4N]+ (7b) in solution, being no NMR evidence for formation of a 1:1 adduct. However, ESMS indicates the presence of both 1:1 and 1:2 adducts in acetonitrile solution.

The syntheses of 1,1′-bis(chloromethyldimethylsilyl)ferrocene, fc(SiMe 2 CH 2 Cl) 2 (2), of the series of open-chain ferrocene-and silicon-containing organotin(IV) compounds 14), and of the ferrocenophanesPh) are reported, and the molecular structures of 4, 16, 17, 19, 20, 22, and 23 are described. In solution, the halogen-substituted ferrocenophanes 17-19 undergo cis-trans isomerization, the rate of which is enhanced by addition of halide ions. Variable-temperature 119 Sn and 19 F NMR studies in solution indicate that the fluoro derivatives 9, 13, and 18 react with different molar equivalents of fluoride ions to give the 1:1 and 1:2 adductsrespectively. A more extended electrochemical investigation points out that the species containing halogen-substituted tin groups are more sensitive to anions than their analogues containing diphenyltin groups.