Alkanesulphonate esters

Reduction of conjugated carbonyl compounds using stoichiometric amounts of the ammonium salt shows little advantage over the sodium salt in acidic methanol [11] with both reagents producing allylic alcohols (58-88% for acyclic compounds and 15-64% for cyclic compounds) by selective 1,2-reduction of the conjugated systems. Aldehydes, ketones and conjugated enones are also reduced by tetra-n-butylammonium cyanoborohydride in HMPA [11, 12], whereas haloalkanes and alkanesulphonic esters are cleaved reductively under similar conditions [13]. 

Metallation of alkanesulphonate esters of alcohols which have been functionalized at the 2- or 3-positions leads to y- and <5-sultones often in good yield. In this way <5-sultone 12 was prepared from propane-1,3-dimethylsulphonate (equation 24) by Durst and Tin49. 

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