The proline-catalyzed double Mannich reaction of acetaldehyde with N-Boc imines.
Double-cross: Proline catalyzes the double Mannich reaction of acetaldehyde with N-Boc imines in excellent yields (up to 99 %; Boc = tert-butoxycarbonyl) and close to perfect diastereo- and enantioselectivities. Depending on the choice of catalysts, both the chiral, pseudo-C(2)-symmetric diastereomer and the corresponding meso compound can be prepared. Cross double Mannich reactions of acetaldehyde with two different imines are also demonstrated.
Chandler
Carley
C
Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
Galzerano
Patrizia
P
Michrowska
Anna
A
List
Benjamin
B
D000079:Acetaldehyde / Q000138:chemical synthesis / Q000737:chemistry*; D002384:Catalysis; D007097:Imines / Q000138:chemical synthesis / Q000737:chemistry*; D011392:Proline / Q000138:chemical synthesis / Q000737:chemistry*; D013237:Stereoisomerism
D007097:Imines; D011392:Proline; D000079:Acetaldehyde