Insights into the Mechanisms and Chemoselectivities of Carbamates and Amides in Rh(II)-Azavinylcarbene Involved Reactions: A Computational Study

Reactions involving Rh(II)-azavinylcarbenes (Rh(II)-AVCs) to synthesize nitrogen-containing compounds have attracted significant research interest. Despite the importance of these reactions, controlling the chemoselectivities in the reactions involving Rh(II)-AVC remains a challenge. To understand the mechanisms and factors controlling the chemoselectivities between N–H and C═O groups of carbamates and amides in reactions involving Rh(II)-AVC, computational studies were employed. The results reveal that not only the greater nucleophilicity of the N−H group than that of the carbonyl group, but also the presence of H-bonding interactions, could favor the addition of the N−H group of primary carbamates to Rh(II)-AVC. However, for secondary carbamates and amides, they could undergo either chemoselective N–H or C═O addition. Secondary carbamates with less steric hindrance, such as oxazolidinone, prefer the N–H addition mode. However, a switch in chemoselectivity (preference for the C═O addition) was revealed f...