Vic-Aminohydroxylation

With cis-vic-aminohydroxylations of unsymmetrical alkenes, however, it may be a problem that two regioisomers occur—a complication that does not occur with cis-vic-dihydroxylations. The addition of (DHQ)2-PHAL or (DHQD)2-PHAL (Figure 17.21, part I) in a cis-vic-aminohydroxylation will also cause asymmetric catalysis. The related reactions are known as asymmetric aminohydroxylations. 

Amino-Hydroxylation. A related reaction to asymmetric dihydroxylation is the asymmetric amino-hydroxylation of olefins, forming v/c-ami noalcohols. The vic-hydroxyamino group is found in many biologically important molecules, such as the (3-amino acid 3.10 (the side-chain of taxol). In the mid-1970s, Sharpless76 reported that the trihydrate of N-chloro-p-toluenesulfonamide sodium salt (chloramine-T) reacts with olefins in the presence of a catalytic amount of osmium tetroxide to produce vicinal hydroxyl p-toluenesulfonamides (Eq. 3.16). Aminohydroxylation was also promoted by palladium.77... 

---