The enamine derived from cyclopentanone and (2R,5R)-2,5-bis(methoxymethyl)pyrrolidine added ethyl N-mesylazidoformimidate [N3C(OEt)NMs] and ethyl azidoformate (N3CO2Et) with high asymmetric induction (>95%), while the corresponding cyclohexanone enamine gave ring contraction products. With the same azides the cyclopentanone enamine, prepared from (S)-2-(methoxymethyl)pyrrolidine gave N-substituted alpha-amino cyclopentanones in moderate enantiomeric excess. (C) 1997 Elsevier Science Ltd.
Stereoselective azide cycloaddition to chiral cyclopentanone enamines / Fioravanti, Stefania; Pellacani, Lucio; Damiano, Ricci; Tardella, Paolo Antonio. - In: TETRAHEDRON-ASYMMETRY. - ISSN 0957-4166. - STAMPA. - 8:13(1997), pp. 2261-2266. [10.1016/s0957-4166(97)00239-5]
Stereoselective azide cycloaddition to chiral cyclopentanone enamines
FIORAVANTI, Stefania;PELLACANI, Lucio;TARDELLA, Paolo Antonio
1997
Abstract
The enamine derived from cyclopentanone and (2R,5R)-2,5-bis(methoxymethyl)pyrrolidine added ethyl N-mesylazidoformimidate [N3C(OEt)NMs] and ethyl azidoformate (N3CO2Et) with high asymmetric induction (>95%), while the corresponding cyclohexanone enamine gave ring contraction products. With the same azides the cyclopentanone enamine, prepared from (S)-2-(methoxymethyl)pyrrolidine gave N-substituted alpha-amino cyclopentanones in moderate enantiomeric excess. (C) 1997 Elsevier Science Ltd.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
