| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1348614 | Tetrahedron: Asymmetry | 2006 | 13 Pages |
New modified chiral auxiliaries (S)-N-(2-benzoylphenyl)-1-(2-chlorobenzyl)pyrrolidine-2-carboxamide (2-CBPB) and (S)-N-(2-benzoylphenyl)-1-(3,4-dimethylbenzyl)pyrrolidine-2-carboxamide (3,4-DMBPB) and their NiII complexes of Schiff’s base with glycine and alanine have been synthesized and tested in asymmetric C-alkylation and aldol condensation reactions of amino acid moieties. The tests proved that both new auxiliaries were efficient with the ee’s of the final amino acids as high as 98% even in case of α-methyl-α-amino acid synthesis.
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(S)-N-(2-Benzoylphenyl)-1-(2-chlorobenzyl)pyrrolidine-2-carboxamide hydrochlorideC25H23ClN2O2·HClEe pure[α]D20=-40.2 (c 1.0, MeOH)Source of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-N-(2-Benzoylphenyl)-1-(3,4-dimethylbenzyl)pyrrolidine-2-carboxamide hydrochlorideC27H28O2N2·HClEe pure[α]D20=-38.5 (c 1.0, MeOH)Source of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-{({2-[1-(2-Chlorobenzyl)pyrrolidine-2-carboxamide]phenyl}phenylmethylene)-glicinato-N,N′,N″,O}nickel(II)C27H24ClN3NiO3Ee pure[α]D20=+2364 (c 0.05, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-{({2-[1-(3,4-Dimethylbenzyl)pyrrolidine-2-carboxamide]phenyl}phenylmethylene)-glycinato-N,N′,N″,O}nickel(II)C29H29N3NiO3Ee pure[α]D20=+1513 (c 0.05, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-{({2-[1-(2-Chlorobenzyl)pyrrolidine-2-carboxamide]phenyl}phenylmethylene)-(S)-alaninato-N,N′,N″,N}nickel(II)C28H26ClN3NiO3Ee pure[α]D20=+2574 (c 0.05, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (S,S)
(S)-{({2-[1-(3,4-Dimethylbenzyl)pyrrolidine-2-carboxamide]phenyl}phenylmethylene)-(S)-alaninato-N,N′,N″,O}nickel(II)C30H31N3NiO3Ee pure[α]D20=+2562 (c 0.05, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (S,S)
