Rhodium-catalyzed Reformatsky-type reaction for asymmetric synthesis of difluoro-β-lactams using menthyl group as a chiral auxiliary
作者:Atsushi Tarui、Daiki Ozaki、Naoko Nakajima、Yuto Yokota、Yasser S. Sokeirik、Kazuyuki Sato、Masaaki Omote、Itsumaro Kumadaki、Akira Ando
DOI:10.1016/j.tetlet.2008.04.101
日期:2008.6
developed a new methodology for the asymmetric Reformatsky-type reaction of (−)-menthyl bromodifluoroacetate (2) with imine in the presence of RhCl(PPh3)3. Ester 2 with the cost-effective chiral auxiliary gave (S)-difluoro-β-lactams in moderate to good yields and high diastereoselectivities through spontaneous removal of the auxiliary.
我们开发了一种新的方法,用于在RhCl(PPh 3)3存在下(-)-薄荷基溴二氟乙酸酯(2)与亚胺的不对称Reformatsky型反应。带有成本有效的手性助剂的酯2通过自发除去助剂,以中等至良好的收率和较高的非对映选择性获得(S)-二氟-β-内酰胺。