One-Pot Synthesis of Chiral α-Methylene-γ-lactams with Excellent Diastereoselectivities and Enantioselectivities
摘要:
An efficient one-pot asymmetric synthesis of highly substituted gamma-lactams containing a-methylene groups has been successfully developed. A wide range of gamma-lactams could be obtained in high yields with excellent diastereomeric ratios of up to 99:1 in favor of trans isomers. In particular, excellent enantioselectivities of the two newly formed stereogenic centers with up to 99% ee were observed.
One-Pot Synthesis of Chiral α-Methylene-γ-lactams with Excellent Diastereoselectivities and Enantioselectivities
摘要:
An efficient one-pot asymmetric synthesis of highly substituted gamma-lactams containing a-methylene groups has been successfully developed. A wide range of gamma-lactams could be obtained in high yields with excellent diastereomeric ratios of up to 99:1 in favor of trans isomers. In particular, excellent enantioselectivities of the two newly formed stereogenic centers with up to 99% ee were observed.
Enantioselective Synthesis of α-Methylene-γ-butyrolactams Using N-tert-Butanesulfinamides
作者:Miguel Yus、Francisco Foubelo、Haythem K. Dema
DOI:10.3987/com-10-s(e)94
日期:——
Indium-mediated coupling of ethyl 2-(bromomethyl)acrylate (1) and chiral N-tert-butanelsulfinylimines 2 in a saturated sodium bromide aqueous solution leads to N-tert-butanesulfinyl aminoesters 3 in high yields and diastereoselectivities. After column chromatography purification, enantiomerically pure aminoesters 3 were converted into the expected alpha-methylene-gamma-butyrolactams 4 in a one-pot process.