Synthesis of homologated binaphthyl N,P-ligands for Pd-catalyzed asymmetric allylic alkylation

2-Pyrrolidinylmethyl-2′-diphenylphosphino-1,1′-binaphthyl has been found to be a highly reactive and enantioselective N,P-ligand in the palladium-catalyzed asymmetric allylic alkylation of 1,3-diphenylpropen-2-yl acetate with dimethyl malonate. This axially chiral binaphthyl-based homologated N,P-ligand can be conveniently prepared from enantiomerically pure binaphthol using a five-step reaction sequence, and provides for efficient asymmetric catalysis using the chirality of the binaphthyl skeleton alone.

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(R)-2-(Pyrrolidine-1-carbonyl)-2′-diphenylphosphinyl-1,1′-binaphthylC37H30NO2PEe = 100%[α]D25=+170.0 (c 1.00, THF)Source of chirality: (R)-binolAbsolute configuration: (R)

(R)-2-(N,N-Dimethylcarbonyl)-2′-diphenylphosphinyl-1,1′-binaphthylC35H28NO2PEe = 100%[α]D25=+192.8 (c 1.00, THF)Source of chirality: (R)-binolAbsolute configuration: (R)

(R)-2-(Piperidinedine-1-carbonyl)-2′-diphenylphosphinyl-1,1′-binaphthylC38H32NO2PEe = 100%[α]D25=+203.1 (c 1.00, THF)Source of chirality: (R)-binolAbsolute configuration: (R)

(R)-2-(Morpholine-4-carbonyl)-2′-diphenylphosphinyl-1,1′-binaphthylC37H30NO3PEe = 100%[α]D25=+179.1 (c 1.00, THF)Source of chirality: (R)-binolAbsolute configuration: (R)

(R)-2-(Pyrrolidinylmethyl)-2′-diphenylphosphino-1,1′-binaphthylC37H32NPEe = 100%[α]D25=+62.0 (c 1.00, CHCl3)Source of chirality: (R)-binolAbsolute configuration: (R)

(R)-2-(Piperidinomethyl)-2′-diphenylphosphino-1,1′-binaphthylC38H34NPEe = 100%[α]D25=+56.3 (c 1.00, CHCl3)Source of chirality: (R)-binolAbsolute configuration: (R)

(R)-2-(Morpholinomethyl)-2′-diphenylphosphino-1,1′-binaphthylC37H32NOPEe = 100%[α]D25=+45.3 (c 1.00, CHCl3)Source of chirality: (R)-binolAbsolute configuration: (R)