NOVEL MOLECULAR ORGANOTIN OXIDES DERIVED FROM ALKYLIDENE BRIDGED DITIN PRECURSORS - SYNTHESES AND STRUCTURES

New diorganotin compounds (RCl2Sn)(2)(CR'(2))(n) [R = (SiMe3)(2)CH; R' = Me, H; n = 1-3] Linked by various spacers have been synthesized. Th ese react with sodium hydroxide or (t-Bu2SnO)(3) to give (R(O)Sn)(2)(C R'(2))(n). Compounds 8 (R' = Me, n = 1), 9 (R' = H, n = 2), and 10 (R' = H, n = 3) contain four-coordinate tin atoms. Compound 9 undergoes a reversible hydrolysis reaction from which a solid containing three di tin units has been isolated. Evidence is presented for the existence i n solution of monomeric four-coordinate tin compounds (RXSn)(2)(CH2)(3 )O [R = (SiMe3)(2)CH, X = Cl, OH]. Crystal structures for monomeric di tin precursors s[bis(trimethylsilyl)methyldichlorostannyl]propane (3) and is[bis(trimethylsilyl)methyldichlorostannyl]ethane (6), for dimeri c units hyl-2,4,6,8-tetraoxa-1,3,5,7-tetrastannaadamantane (8), ricycl o[7.3.1.13.7]-1,3,7,9-tetrastannatetradecane (10), and imethylsilyl)me thyl]-1-oxa-2,6-distannacyclohexane dimer (12), and for trimeric units {O[(RSn(CH2)(2)SnR)OH]OH}(3). 2H(2)O (9a) are reported.