Solvent effects on the diastereoselection in LiAlH4 reduction of α-substituted ketones

Based on high-level DFT calculations including solvent molecules, it was found that steric effects of solvent may be responsible for the diastereoselection in LiAlH4 reduction of acyclic ketones substituted by an oxygen-containing functional group at the α-position to the carbonyl. It was concluded that the conventional chelated transition state models lead to the predominance of the R∗,S∗-diastereoisomers against experimental observation.