â-Ketoallylsilanes are synthesized by the Horner-Emmons reaction starting from novel silylated ketophosphonates and various aldehydes. The reactions of â-ketoallylsilanes with NsONHCO2Et and CaO produce R-methylene-N-(ethoxycarbonyl)- â-amino ketones through the ring opening of the intermediate aziridine, which is favored by the presence of the trimethylsilyl group. With chiral â-ketoallylsilanes we obtained a stereoselective amination reaction with a 90% diastereomeric excess. R-Methylene-N-(ethoxycarbonyl)-â- amino ketones are isolated in 39-60% yields and characterized
α-Methylene- β-amino Ketone Derivatives from β-Ketoallylsilanes / Loreto, Maria Antonietta; Migliorini, Antonella; Tardella, Paolo Antonio. - In: JOURNAL OF ORGANIC CHEMISTRY. - ISSN 0022-3263. - STAMPA. - 71:(2006), pp. 2163-2166. [10.1021/jo052330d]
α-Methylene- β-amino Ketone Derivatives from β-Ketoallylsilanes
LORETO, Maria Antonietta;MIGLIORINI, Antonella;TARDELLA, Paolo Antonio
2006
Abstract
â-Ketoallylsilanes are synthesized by the Horner-Emmons reaction starting from novel silylated ketophosphonates and various aldehydes. The reactions of â-ketoallylsilanes with NsONHCO2Et and CaO produce R-methylene-N-(ethoxycarbonyl)- â-amino ketones through the ring opening of the intermediate aziridine, which is favored by the presence of the trimethylsilyl group. With chiral â-ketoallylsilanes we obtained a stereoselective amination reaction with a 90% diastereomeric excess. R-Methylene-N-(ethoxycarbonyl)-â- amino ketones are isolated in 39-60% yields and characterizedI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
