Ironing Out Carbonyl Reduction Reactions

Reducing carbonyl compounds to make alcohols is among the most widely used reactions in lab and industrial organic synthesis. One approach involves heating an aldehyde or ketone with a silane reducing agent and platinum-group catalyst to create a hydrosilyl intermediate that is hydrolyzed to form the alcohol. In an industry-academic collaboration, a research team has now developed an iron catalyst for carbonyl hydrosilylations that is less expensive than platinum-group catalysts, requires less catalyst, and works on a broader range of carbonyl compounds than previously reported (Organometallics 2013, DOI: 10.1021/om400883u). Building on recent developments on N-phosphinoamidine ligands, the researchers, led by Mark Stradiotto and Laura Turculet of Dalhousie University, in Halifax, Nova Scotia, and Orson L. Sydora of Chevron Phillips Chemical, in Kingwood, Texas, developed the new iron catalyst (shown). The team’s hydrosilylations run at room temperature and require only 1 mol % or less of catalyst and only one equivalent of phenylsilane. Besides working efficiently on a variety of aldehydes and ketones under mild conditions, the reaction also converts esters to alcohols, which is a first for iron-catalyzed hydrosilylations.