Catalytic Enantioselective Synthesis of Lactams through Formal [4+2] Cycloaddition of Imines with Homophthalic Anhydride. Issue 10 (27th January 2017) - Jarvis, Claire L.
Abstract: An amide‐thiourea compound, operating through a novel ion pairing mechanism, is an efficient organocatalyst for the asymmetric reaction of homophthalic anhydride with imines. N ‐aryl and N ‐alkyl imines readily undergo formal [4+2] cycloaddition to provide lactams with high levels of enantio‐ and diastereoselectivity. The nature of the key chiral ion pair intermediate was elucidated by DFT calculations. Abstract : Get it together : An amide‐thiourea compound, operating through a novel ion‐pairing mechanism, is an efficient organocatalyst for the asymmetric reaction of homophthalic anhydride with imines. N ‐aryl and N ‐alkyl imines readily undergo the formal [4+2] cycloaddition to provide lactams with high levels of enantio‐ and diastereoselectivity. The nature of the key chiral ion pair intermediate was elucidated by DFT calculations.