Making Amines And Alcohols Enantioselectively

Chiral amine and alcohol functional groups dominate the landscape of biologically relevant molecules, such as drugs and agrochemicals. So chemists are always on the lookout for ways to make such moieties. Chemists at Boston College, led by Amir H. Hoveyda and his team, which includes graduate student Daniel L. Silverio, have come up with a simple way to synthesize amines and alcohols enantio­selectively (Nature, DOI: 10.1038/nature11844). The reaction adds an allyl group, from an allylboronic ester, to an activated imine (shown) or to an electron-deficient carbonyl. The key component in the transformation is an organic catalyst that orchestrates the enantioselective carbon-carbon bond-forming reaction. The researchers prepare the catalyst from the abundant amino acid valine in just four steps through the use of inexpensive reagents. As little as 0.25 mol% is all that’s needed of the catalyst to produce allylamines and allyl alcohols in more than 85% yield with high enantioselectivity. Furthermore, the reaction takes place in common solvents at room temperature in less than six hours. The team now aims to use this catalyst system to develop other efficient and enantioselective C–C bond-forming reactions.