Reversal of facial selectivity in a thia-Claisen rearrangement by incorporation of a vinylic bromine substituent.

Thia-Claisen rearrangements have been carried out using N-benzylpyrrolidine-2-thione and chiral allylic bromides derived from D-mannitol. Introduction of a bromine atom onto the double bond of the allylic bromide reverses the sense of diastereoselectivity in the [3,3]-sigmatropic rearrangement. Density functional theory calculations lead us to rationalise the observed selectivity in terms of a Cíeplak effect.

A direct and efficient preparation of 1-phenyltetrazol-5-yl sulfides from alcohols.

Treatment of primary or secondary alcohols with 1-phenyl-1(H)-tetrazole-5-thiol and [Me(2)NCHSEt](+) BF(4)(-) leads directly and cleanly to 1-phenyl-1(H)-tetrazol-5-yl sulfides.

Selective conversion of alcohols into alkyl iodides using a thioiminium salt.

Treatment of a range of primary and secondary alcohols with MeSCH=NMe(2)(+) I(-) affords the corresponding alkyl iodides in excellent yield with straightforward purification. Selective formation of a primary iodide in the presence of a secondary alcohol can be achieved.