Regioselective Oxyselenenylation

Catalytic regioselective oxidation of glycosides.

Discrimination among equals: A catalytic method for the selective oxidation of unprotected glycosides, both monosaccharides and disaccharides, has been developed. The resulting ketosaccharides are isolated in moderate to excellent yields. This approach provides a basis for protecting-group-free synthetic transformations of carbohydrates.

Regioselective modification of unprotected glycosides.

Selective modification of unprotected carbohydrates is difficult due to the similar reactivity of the hydroxyl groups. In carbohydrate synthesis, therefore, even straightforward transformations often require multiple synthetic steps. The development of selective methods for carbohydrate modification is consequently highly desired. This review describes the methods for the regio- and chemoselect...

Regioselective electrophilic borylation of haloarenes.

Haloarenes undergo direct borylation using amine : BCl3 : AlCl3 in the ratio of 1 : 1 : 2. After esterification the pinacol boronate esters are isolated in good yield with regioselectivity controlled by steric and electronic effects.

Highly regioselective osmium-catalyzed hydroformylation.

The first highly regioselective and general osmium-catalyzed hydroformylation of olefins to aldehydes is reported. The combination of Os3(CO)12 and imidazoyl-substituted phosphine ligands allows n-selective (up to 99%) hydroformylation of bulk aliphatic as well as functional alkenes in good yields (64-87%).

Regioselective Rhodium-Catalyzed Allylic Amination