Dechlorination, with tributyltin

Both products were dechlorinated with tributyltin hydride in refluxing cyclohexant containing a catalytic amount of azobisisobutyronitrile. 

Trichloroethylidene acetals are readily dechlorinated by tributyltin hydride, thus providing convenient access to ethylidene acetals with endo-H configuration. ... 

Ketene itself and simple alkylketenes are inert towards nonactivated alkenes. F or the preparation of cyclobutanones formally derived from ketene or an alkylketene and nonactivated alkenes, the more reactive dichloroketene or alkylchloroketenes can be used. The corresponding a,a-dichloro- or oc-chlorocyclobutanones can readily be dechlorinated by treatment with zinc in acetic acid, or tributyltin hydride in near quantitative yields. F or example cycloaddition of substituted cyclohexene to dichloroketene gave dichlorocyclobutanone 1 which was dechlorinated to 2 with zinc.13,18 Likewise cycloaddition of cycloalkcnes to chloro(methyl)ketene gave 3 which was dechlorinated to 4.14... 

Dechlorination of 4-chloro-6-methylthieno[2,3-d]pyrimidine 164 with zinc in ethanol and acetic acid at 80°C gave compound 165. The latter was subjected to the Reissert reaction using two equivalents each of tributyltin cyanide and acyl chloride in dichloromethane at room temperature. With benzoyl chloride the mono-Reissert adduct 166 was obtained, whereas with acetyl chloride the di-Reissert product 167 (86JHC545). 

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