Recoverable resin-supported pyridylamide ligand for microwave-accelerated molybdenum-catalyzed asymmetric allylic alkylations: enantioselective synthesis of baclofen.
The syntheses of a series of 4-monosubstituted pyridylamides and a resin-supported pyridylamide are described. The ligands were evaluated in the microwave-accelerated molybdenum-catalyzed asymmetric allylic alkylation. The reaction afforded the product in high yield and with high regio- and enantioselectivity. The heterogeneous ligand could be reused several times with no change in the reaction outcome. The asymmetric allylic alkylation was employed as the key step in the enantioselective synthesis of (R)-baclofen. [reaction: see text]
Belda
Oscar
O
Department of Chemistry, Organic Chemistry, KTH, SE-100 44 Stockholm, Sweden.
Lundgren
Stina
S
Moberg
Christina
C
D000478:Alkylation; D000498:Allyl Compounds / Q000737:chemistry*; D000577:Amides / Q000737:chemistry*; D001418:Baclofen / Q000138:chemical synthesis*; D002384:Catalysis; D008024:Ligands; D008872:Microwaves; D008982:Molybdenum / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*; D013237:Stereoisomerism
D000498:Allyl Compounds; D000577:Amides; D008024:Ligands; D011725:Pyridines; D008982:Molybdenum; D001418:Baclofen