| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1350755 | Tetrahedron: Asymmetry | 2006 | 5 Pages |
New BINAM-prolinamides were developed and tested as organocatalysts in the direct aldol condensation between aldehydes and several aliphatic ketones. C2-symmetrical (Sa)-BINAM-l-prolinamide gives the best enantioselectivities for this transformation, being recovered and reused after the reaction by simple extractive techniques. The reaction was performed in DMF/H2O at 0 °C to give the aldol products in up to 95% ee for acetone. For 2-butanone, the corresponding iso-regioisomers were regioselectively obtained in up to 96% ee working in DMF at rt. In the case of cyclohexanone, dr up to 10:1 in favour of the anti products, which were obtained in 90–93% ee, was achieved.
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(2S)-N-(1-((S)-2-((S)-Pyrrolidine-2-carboxamido)naphthalen-1-yl)naphthalen-2-yl)pyrrolidine-2-carboxamideC30H30N4O2[α]D26=-108.6 (c 1, MeOH)Source of chirality: Commercially available (Sa)-BINAMAbsolute configuration: Sa, S
(2R)-N-(1-((S)-2-((S)-Pyrrolidine-2-carboxamido)naphthalen-1-yl)naphthalen-2-yl)pyrrolidine-2-carboxamideC30H30N4O2[α]D25=+6.7 (c 1, MeOH)Source of chirality: Commercially available (Ra)-BINAMAbsolute configuration: Ra, S
(2S)-N-((S)-1-(2-Aminonaphthalen-1-yl)naphthalen-2-yl)pyrrolidine-2-carboxamideC25H23N3O[α]D29=-87.4 (c 1, MeOH)Source of chirality: Commercially available (Sa)-BINAMAbsolute configuration: Sa, S
