The stereochemical control in the generation of new stereogenic centers is of paramount importance in organic chemistry. In this context, diastereoselective additions to carbonyl compounds bearing a stereogenic center at the α-position are of particular importance, since an increase in molecular complexity can be achieved by constructing a new bond, together with the introduction of a new stereocenter. Despite the relevance of the topic, it is discussed only briefly in several of the most popular organic chemistry textbooks, or not discussed at all. The present article intends to discuss the evolution of stereochemical models for 1,2-induction and present to students a tool to understand and predict the stereochemical outcome of addition of nucleophiles to aldehydes and ketones bearing a stereogenic center at the α-position.
Keywords:
stereochemistry; diastereoselectivity; carbonyl compounds; Felkin-Anh; Cram-chelate
