Metallostannation of Alkenes and Alkynes

6 The Reaction of Acidic Hydrocarbons with Sn-O and Sn-N Bonded Compounds 

If A is derived from a weak acid HA, and HC is a strong hydrocarbon acid, the SnC bond can be formed by the acidolysis reaction  

HA Is usually a volatile amine which can readily be removed to drive an equilibrium reaction to completion. Reactions of this type are useful for preparing cyclopentadienyl-, alkynyl-, trihalogenomethyl-, and diazoalkyl-tin compounds. 

Some examples are given in equations 4-71-4-75, and more are to be found in the sections dealing with the respective specific classes of organotin compounds which are formed. Cyclopentadiene can be both mono- and di-stannylated, and triphenylindenyltin has been obtained from indene (Section 9.3.1).116 Acetylene can be both mono-and di-stannylated,116-117 and the reaction of a diaminotin compound with acetylene gives a linear polymer.116-118 The acidity of sulphonylalkynes is sufficient to allow the reaction to be carried out with a tin alkoxide rather than a tin amide,119 and acetylenes can be stannylated with tributyltin oxide in benzene by dehydration with calcium hydride, or azeotropically.120 

Chloroform and bromoform react readily at room temperature to give the trihaloge-nomethyltin compounds in good yield 121-122 trichloroethene reacts similarly,122 and so does pentafluorobenzene. 

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