186352-26-1Relevant academic research and scientific papers
Intramolecular Enantioselective Palladium-Catalyzed Heck Arylation of Cyclic Enamides
Ripa, Lena,Hallberg, Anders
, p. 595 - 602 (1997)
Palladium-catalyzed intramolecular cyclization of N-formyl-6--1,2,3,4-tetrahydropyridine (1a) and N-formyl-6--1,2,3,4-tetrahydropyridine (1b) in the presence of AsPh3 resulted in formation of the spiro compounds N-formyl-3,3',4,4'-tetrahydrospiro (2a) and N-formyl-3',4'-dihydrospiro (2b), respectively, and in the presence of PPh3 and TlOAc in the spiro compounds N-formyl-3,4,5',6'-tetrahydrospiro (3a) and N-formyl-5',6'-dihydrospiro (3b), respectively.Cyclization of N-formyl-6-(3-phenyl>propyl)-1,2,3,4-tetrahydropyridine (7) in presence of a chiral (phosphinoaryl)oxazoline ((S)-8) resulted in formation of (R)-3a and (R)-N-formyl-1',3,4,6'-tetrahydrospiro ((R)-6a) in high enantiomeric excesses, 87 percent and >99percent, respectively, and in good yield.The oxazoline ligand (S)-8 furnished higher enantiomeric excesses and improved regioselectivities than (R)-BINAP.
