Alkoxy- substituted aryl- and benzyl- organotin compounds
New organotin compounds containing alkoxy- functionalities have been prepared. The methods of preparation of the tetraorganotin species have involved three routes. Hydrostannation reactions using triphenyltin hydride have resulted in the synthesis of triphenyltin derivatives of a series of alkoxy- substituted allyl ethers. The addition of tin IV chloride, diphenyltin dichloride and phenyltin trichloride to alkoxy- substituted aryl- and benzyl- Grignard reagents have also been successful. Alkoxy- substituted benzyltin compounds have been prepared by following an alternative preparation of benzylmagnesium halides from that commonly used to prepare Grignard reagents. Nucleophilic substitution of (iodomethyl)triphenyltin by a novel ligand has been effective. The structures of the products have been investigated by 1H, 13C and 119Sn nmr. Single crystal X-ray diffraction studies have led to the determination of the crystal structures of tetra-2-anisyltin, tetrakis-(2-methoxybenzyl)tin and N,N'-bis(5-triphenylstannoxymethyl-2-phenyl-1,3-dioxan-5-yl)ethanediamide. Selective tin-carbon bond cleavage has been effected by the use of iodine and bromine to give rise to mono- and dihalo- organotin compounds and the crystal structures of tri-2-anisyltin iodide and di-2-anisyltin dibromide have been elucidated by X-ray crystallography. Chloro(3-ethoxypropyl)diphenyltin has been synthesised directly from diphenyltin dichloride and has been found to contain a penta-co-ordinate tin centre with a four membered chelate ring as a result of intramolecular tin-oxygen co-ordination. Other tin-carbon bond cleavage reactions by halogens have been studied by 1H and 119Sn nmr and GLC and the results discussed.