Pyridine N-Oxide Derivative

4-Phenylpyridine N-oxide (1) is used as a co-catalyst in the enantioselective epoxidation of unfunctionalized olefins using chiral (salen)manganese(III) complexes as catalysts. For example, in the presence of 1 and Jacobsenﾕs catalyst, epoxyindan 2 is obtained in relatively high enantioselectivity by the oxidation of indene with sodium hypochlorite. Merck's HIV protease inhibitor Crixivan^® is synthesized from epoxyindan 2 via chiral aminoindanol 3.^1,2)