Enantioselective Synthesis of (+)‐Ricciocarpin A Using an Auxiliary Hydroxyl Group and a Diastereofacial Selectivity Based Methodology.

CO2-Enabled Cyanohydrin Synthesis and Facile Homologation Reactions

“…HCl) afforded only low yield of the product since HCN (a "slower" nucleophile) generation is favored (entry 14). The use of acetic acid 26 showed compatible result (entry 15) confirming that weak acid can indeed catalyze the reaction, by prohibiting the complete protonation of KCN. The role of CO2 in the cyanohydrin synthesis was further verified by adding catalytic amounts of CO2 (20 mol%) to a reaction mixture repeatedly (Figure 2).…”