A versatile synthesis of phosphine–aminophosphine ligands for asymmetric catalysis

A new and versatile synthesis of phosphine–aminophosphine ligands allows the incorporation of a wide range of nitrogen and phosphorus substituents into these ligands, several of which exhibit improved properties for rhodium-catalyzed asymmetric hydrogenation reactions. This synthesis also allows the preparation of mixed phosphine–phosphoramidite species.

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N-Diphenylphosphino-N-methyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC37H35FeNP2Ee = >99%[α]D24=-257 (c 0.96, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Diphenylphosphino-N-isopropyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC39H39FeNP2Ee = >99%[α]D24=-196 (c 1.03, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Diphenylphosphino-N-2,2-dimethylpropyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC41H43FeNP2Ee = >99%[α]D24=-312 (c 0.55, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Diphenylphosphino-N-tert-butyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC40H41FeNP2Ee = >99%[α]D24=-153 (c 1.02, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Diphenylphosphino-N-phenyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC42H37FeNP2Ee = >99%[α]D24=-381 (c 1.02, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Benzyl-N-diphenylphosphino (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC43H39FeNP2Ee = >99%[α]D24=-326 (c 1.02, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Diphenylphosphino-N-(S)-1-phenylethyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC44H41FeNP2Ee = >99%[α]D24=-218 (c 0.54, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Diphenylphosphino-N-(R)-1-phenylethyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC44H41FeNP2Ee = >99%[α]D24=-69.4 (c 1.02, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Bis(4-methylphenyl)phosphino-N-methyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC39H39FeNP2Ee = >99%[α]D24=-219 (c 0.99, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Bis(3,5-dimethylphenyl)phosphino-N-methyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC41H43FeNP2Ee = >99%[α]D24=-255 (c 0.51, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Bis(4-methoxyphenyl)phosphino-N-methyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC39H39FeNO2P2Ee = >99%[α]D24=-169 (c 0.39, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Bis(3-fluorophenyl)phosphino-N-methyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC37H33F2FeNP2Ee = >99%[α]D24=-263 (c 0.97, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Bis(4-fluorophenyl)phosphino-N-methyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC37H33F2FeNP2Ee = >99%[α]D24=-267 (c 1.01, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Bis(4-chlorophenyl)phosphino-N-methyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC37H33Cl2FeNP2Ee = >99%[α]D24=-181 (c 1.01, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Bis(3,4-difluorophenyl)phosphino-N-methyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC37H31F4FeNP2Ee = >99%[α]D24=-221 (c 0.91, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Bis(3,4-dichlorophenyl)phosphino-N-methyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC37H31Cl4FeNP2Ee = >99%[α]D24=-226 (c 1.01, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Bis(3,5-difluorophenyl)phosphino-N-methyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC37H31F4FeNP2Ee = >99%[α]D24=-268 (c 1.02, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Bis(3,5-dichlorophenyl)phosphino-N-methyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC37H31Cl4FeNP2Ee = >99%[α]D24=-203 (c 1.00, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Bis(phenoxy)phosphino-N-methyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC37H35FeNO2P2Ee = >99%[α]D24=-272 (c 1.01, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Bis(4-methoxyphenoxy)phosphino-N-methyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC39H39FeNO4P2Ee = >99%[α]D24=-256 (c 0.94, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-Bis(4-trifluoromethylphenoxy)phosphino-N-methyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC39H33F6FeNO2P2Ee = >99%[α]D25=-258 (c 0.99, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S)

N-R-1,1′-Bi-2-napthyldioxyphosphino-N-methyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC45H37FeNO2P2Ee = >99%[α]D25=-329 (c 0.51, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S,Ra)

N-S-1,1′-Bi-2-napthyldioxyphosphino-N-methyl (R)-1-((S)-2-diphenylphosphino)ferrocenylethylamineC45H37FeNO2P2Ee = >99%[α]D25=-92.9 (c 0.52, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (1R,2S,Sa)