A New Route to Substituted Dihydropyrans
31 December 2000 (online)
Deprotonation and subsequent alkylation of 3,4-dihydro-6-(para-toluenesulfonylmethyl)-2H-pyran gives monoalkylated products in good yields, with excellent α selectivity. The alkylation succeeds not only for reactive haloalkanes, but also for simple primary and secondary alkyl bromides. Desulfonylation with sodium amalgam provides a new and simple route to substituted dihydropyrans.
free radicals - sulfones - dihydropyrans - alkylation - desulfonylation