ABSTRACT
Anilines generally act as N-nucleophiles in transition-metal-catalyzed allylic substitution reactions. In this paper, a highly enantioselective intramolecular Friedel-Crafts-type allylic alkylation of aniline derivatives was realized by using an iridium catalyst derived from [Ir(cod)Cl]2 and (Ra )-BHPphos. Various tetrahydroisoquinilin-5-amines were obtained in moderate to good yields, excellent enantioselectivity and regioselectivity under mild reaction conditions. BHPphos=N-benzhydryl-N-phenyldinaphthophosphoramidite.
ABSTRACT
Palladium-catalyzed asymmetric intramolecular Friedel-Crafts type allylic alkylation reaction of phenols was developed under mild conditions. In the presence of Pd2(dba)3 with (1R,2R)-DACH-phenyl Trost ligand (L2) in toluene at 50 °C, the reaction provides various C4 substituted tetrahydroisoquinolines with moderate to excellent yields, regioselectivity and enantioselectivity.
Subject(s)
Palladium/chemistry , Phenols/chemistry , Tetrahydroisoquinolines/chemistry , Alkaloids/chemistry , Alkylation , Carbon/chemistry , Catalysis , Ligands , Magnetic Resonance Spectroscopy , Metals/chemistry , Solvents/chemistry , Stereoisomerism , Substrate Specificity , Temperature , Time Factors , Toluene/chemistry , Transition Elements/chemistryABSTRACT
Enantioselective Pd(II)-catalyzed direct coupling of aminomethylferrocene derivatives with boronic acids was realized. With commercially available Boc-L-Val-OH as a ligand, planar-chiral ferrocenes could be synthesized in yields of 14-81% with up to 99% ee under mild conditions.