Usage of alfa-picoline borane for the reductive amination of carbohydrates

COSENZA, VANINA A; NAVARRO, DIEGO A; STORTZ, CARLOS A

Arkivoc

ARKAT USA

Año: 2011 vol. 7 p. 182 - 194

1424-6376

The reaction of reductive amination, widely used for carbohydrates, was reviewed in our lab, especially in the context of the analytical determination of carbohydrate enantiomers. The best conditions for the technique have been evaluated, showing that under optimal working conditions it is possible to use á-picoline borane as a reducing agent instead of sodium cyanoborohydride without affecting the selectivity or the yield. The main reason for the variation of the technique was that, in the presence of acetic acid, secondary epimeric products were produced with á-picoline borane due to an Amadori rearrangement. This new modification assures lower toxicity, and thus a more environmental-friendly reaction system. Preparative scale synthesis can also be efficiently made with this reducing reagentá-picoline borane as a reducing agent instead of sodium cyanoborohydride without affecting the selectivity or the yield. The main reason for the variation of the technique was that, in the presence of acetic acid, secondary epimeric products were produced with á-picoline borane due to an Amadori rearrangement. This new modification assures lower toxicity, and thus a more environmental-friendly reaction system. Preparative scale synthesis can also be efficiently made with this reducing reagentá-picoline borane due to an Amadori rearrangement. This new modification assures lower toxicity, and thus a more environmental-friendly reaction system. Preparative scale synthesis can also be efficiently made with this reducing reagent