Alkyltin hydride compounds

The opposite polarity in the organotin reagent R3Sn5+X5 can be exploited in, for example, the reaction of a tin alkoxide with an vinyl ester,83 the addition of an alkoxy- or amino-tin compound to a ketene,84 the reaction of a silyl enolate with a tin chloride,85 or the addition of an alkyltin hydride under non-radical conditions to an a,P-unsaturated carbonyl compound.86... 

Tin-tin bonds are usually best prepared by reducing an Sn-0 or Sn-N bonded compound with a tin hydride. For example, trimethyl (diethylamino)tin is reduced by alkyltin trihydrides to give decaorganotetratins (256). 

Hattori [77] extracted alkyl and alkyltin compounds from sediments with methanoic hydrochloric acid and then, following mixture with sodium chloride and water, the mixture was extracted with benzene and converted to hydrides with sodium borohydride and analysed by gas chromatography using an electron capture detector. Down to 0.02mg kg 1 organotin compounds in sediments could be determined with a recovery of 70-95%. 

Donard, O.F.X., S. Rapsomanikis, and J.H. Weber. 1986. Speciation of inorganic tin and alkyltin compounds by atomic absorption spectrometry using electrothermal quartz furnace after hydride generation. Anal. Chem. 58 772-777. 

The stabilisation of a carbocation by hyperconjugation by a P-C-Sn bond is sometimes referred to simply as the P-tin effect. It is apparent in the abstraction of hydride by Ph3C+ BF4 from alkyltin compounds.19 Tetramethyltin is unreactive, but ethyltin compounds undergo elimination. 

Trialkylstannylalkyl)phosphonates, R3SnCHR P(0)(0R")2> can be prepared by lithia-tion of the alkylphosphonate followed by reaction with the alkyltin chloride (equation 6-20),56 or by an Arbuzov reaction between an iodomethyltin compound and a phosphite (equation 6-21).57 The activated Sn-C bond will then add to a dipolar double bond, and the phosphonate group can be reduced to CH2PH2 with lithium aluminium hydride. 

The synthesis of alkyltins from olefins and organic tin halides becomes particularly smooth in the presence of compounds that decompose to radicals at relatively low temperatures use of azoisobutyronitrile and azoisobutyric esters have proved valuable. Many different types of terminal alkene can be hydrostannated at 30-80° in a very short time by hydrides of types R3SnH, R2SnH2, and RSnH3 443... 

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