Application of ferrocenyl substituted aziridinylmethanols (FAM) as chiral ligands in enantioselective conjugate addition of diethylzinc to enones

Easily available ferrocenyl substituted aziridinylmethanol FAM-4a complexes with nickel and catalyzes the enantioselective diethylzinc addition to various enones with enantiomeric excesses reaching 80%. The ligand can be recovered and used without losing its activity. The sense of induction was found to be dependent on the configuration of the aziridine ring.

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Ferrocenyl((S)-1-((S)-1-phenylethyl)aziridin-2-yl)methanoneC21H21FeNOEe = 99%[α]D25 = −90.0 (c 1.00, CHCl3)Source of chirality: l-α-methylbenzylamine 99% eeAbsolute configuration: (S,S)

Ferrocenyl((R)-1-((S)-1-phenylethyl)aziridin-2-yl)methanoneC21H21FeNOEe = 99%[α]D25 = −220.0 (c 1.00, CHCl3)Source of chirality: l-α-methylbenzylamine 99% eeAbsolute configuration: (R,S)

(R)-Ferrocenyl((S)-1-((S)-1-phenylethyl)aziridin-2-yl)methanolC21H23FeNOEe = 99%[α]D25 = −45.2 (c 1.00, CHCl3)Source of chirality: l-α-methylbenzylamine 99% eeAbsolute configuration: (R,S,S)

(S)-Ferrocenyl((S)-1-((S)-1-phenylethyl)aziridin-2-yl)methanolC21H23FeNOEe = 99%[α]D25 = −46.3 (c 1.00, CHCl3)Source of chirality: l-α-methylbenzylamine 99% eeAbsolute configuration: (S,S,S)

(S)-Ferrocenyl((R)-1-((S)-1-phenylethyl)aziridin-2-yl)methanolC21H23FeNOEe = 99%[α]D25 = −20.9 (c 1.00, CHCl3)Source of chirality: l-α-methylbenzylamine 99% eeAbsolute configuration: (S,R,S)

(R)-Ferrocenyl((R)-1-((S)-1-phenylethyl)aziridin-2-yl)methanolC21H23FeNOEe = 99%[α]D25 = −3.0(c 1.00, CHCl3)Source of chirality: l-α-methylbenzylamine 99% eeAbsolute configuration: (R,R,S)

(R)-1,3-Diphenylpentan-1-oneC17H18OEe = 80%[α]D25 = −4.3 (c 1.35, EtOH)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(−)-1-Phenyl-3-p-tolylpentan-1-oneC18H20OEe = 72%[α]D25 = −9.4 (c 2.22, EtOH)Source of chirality: asymmetric synthesis

(+)-3-(4-(Trifluoromethyl)phenyl)-1-phenylpentan-1-oneC18H17F3OEe = 70%[α]D25 = +4.2 (c 1.92, EtOH)Source of chirality: asymmetric synthesis

(R)-3-(4-Chlorophenyl)-1-phenylpentan-1-oneC17H17ClOEe = 70%[α]D25 = −1.8 (c 1.97, EtOH)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(R)-3-(4-Methoxyphenyl)-1-phenylpentan-1-oneC18H20O2Ee = 76%[α]D25 = −12.4 (c 1.49, EtOH)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(−)-3-(3-Methoxyphenyl)-1-phenylpentan-1-oneC18H20O2Ee = 80%[α]D25 = −3.4 (c 2.06, EtOH)Source of chirality: asymmetric synthesis

(R)-3-(2-Methoxyphenyl)-1-phenylpentan-1-oneC18H20O2Ee = 66%[α]D25 = −5.7 (c 1.80, EtOH)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(+)-3-(2-Chlorophenyl)-1-phenylpentan-1-oneC17H17ClOEe = 50%[α]D25 = +16.4 (c 1.30, EtOH)Source of chirality: asymmetric synthesis

(+)-3-(2-Fluorophenyl)-1-phenylpentan-1-oneC17H17FOEe = 76%[α]D25 = +10.0 (c 2.19, EtOH)Source of chirality: asymmetric synthesis

(+)-3-(Naphthalen-2-yl)-1-phenylpentan-1-oneC21H20OEe = 78%[α]D25 = +1.1 (c 1.99, EtOH)Source of chirality: asymmetric synthesis

(+)-3-Ferrocenyl-1-phenylpentan-1-oneC21H22FeOEe = 56%[α]D25 = +42.9 (c 0.84, EtOH)Source of chirality: asymmetric synthesis

(R)-4-Phenylhexan-2-oneC14H22OEe = 22%[α]D25 = −3.5 (c 1.61, EtOH)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(R)-3-Methyl-1-phenylpentan-1-oneC14H22OEe = 60%[α]D25 = −10.4 (c 1.87, Et2O)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(S)-3-Cyclohexyl-1-phenylpentan-1-oneC17H24OEe = 70%[α]D25 = +0.7 (c 1.54, EtOH)Source of chirality: asymmetric synthesisAbsolute configuration: (S)