A novel type of bidentate hydrogen bond donor catalysts based on (thio)phosphorodiamides catalophore has been developed for the asymmetric Michael addition of 2-hydroxy-1,4-naphthoquione to nitroolefins, affording the corresponding adducts in high yields with excellent level of enantioselectivities (97- >99% ee).

A bifunctional squaramide based on (R,R)‐11,12‐diamino‐9,10‐ethylene‐9,10‐dihydroanthracene has been developed, and it has demonstrated great advantages over previously reported organocatalysts in the asymmetric Michael addition of 4‐hydroxycoumarins to β,γ‐unsaturated α‐oxophosphonates. Upon quenching the generated β‐4‐hydroxy‐2‐oxo‐2H‐chromen‐3‐yl‐substituted acylphosphonate intermediates with DBU and an alcohol or amine as a second nucleophile, the corresponding β‐substituted carboxylates or amides were obtained in acceptable to excellent yields and with high levels of enantioselectivity (80–97 % ee) in a one‐pot fashion.

No abstract

The structurally rigid, new bifunctional squaramide organocatalyst shown demonstrates great advantages over previously reported thiourea or squaramide catalysts in terms of activity and enantioselectivity in the title Michael addition reaction.