Nitrogen source, Sharpless asymmetric

In 1975 Sharpless and coworkers discovered the stoichiometric aminohydrox-ylation of alkenes by alkylimido osmium compounds leading to protected vicinal aminoalcohols [1,2]. Shortly after, an improved procedure was reported employing catalytic amounts of osmium tetroxide and a nitrogen source (N-chlo-ro-N-metallosulfonamides or carbamates) to generate the active imido osmium species in situ [3-8]. Stoichiometric enantioselective aminohydroxylations were first reported in 1994 [9]. Finally, in 1996 the first report on a catalytic asymmetric aminohydroxylation (AA) was published [10]. During recent years, several reviews have covered the AA reaction [11-16]. 

Bruncko, M., Schlingloff, G., Sharpless, K. B. N-Bromoacetamide - a new nitrogen source for the catalytic asymmetric aminohydroxylation of olefins. Angew. Chem., Int. Ed. Engl. 1997, 36, 1483-1486. 

Demko, Z. P., Bartsch, M., Sharpless, K. B. Primary Amides. A General Nitrogen Source for Catalytic Asymmetric Aminohydroxylation of Olefins. Org. Lett. 2000, 2, 2221-2223. 

Recently, Sharpless and co-workers have reported an enantioselective procedure for the vicinal addition of a hydroxyl group and amino-substituted heterocycles to olefins. They have found that simple aminopyrimidines and amino-triazines function as excellent reagents for the asymmetric aminohydroxylation. Stilbene is converted into either enantiomer of the corresponding amino alcohol with high ee s with 2-aminotriazines as the nitrogen source <1999AGE1080>. 

In 1996, Sharpless reported that modification of the AD reaction, by the inclusion of a nitrogen source, which also functions as an oxidant, gives an asymmetric aminohydroxylation (AA). > ... 

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