Conjugate addition of 1,3-dicarbonyl compounds to maleimides using a chiral C2-symmetric bis(2-aminobenzimidazole) as recyclable organocatalyst.
The recyclable chiral 2-aminobenzimidazole-derived organocatalyst 1f efficiently promotes the room temperature asymmetric conjugate addition of 1,3-diketones, β-ketoesters, and malonates to maleimide and N-substituted maleimides, affording the corresponding Michael adducts in excellent yields and enantioselectivities even at gram scale.
Departamento de Química Orgánica & Instituto de Síntesis Orgánica, Universidad de Alicante, Carretera de San Vicente del Raspeig s/n, E-03690, San Vicente del Raspeig, Alicante, Spain.
Eduardo
E
Gómez-Torres
Diego A
DA
Alonso
Enrique
E
Gómez-Bengoa
Carmen
C
Nájera