A PPh3-catalyzed sequential annulation reaction to construct cyclopentane-fused dihydropyrazolone-pyrrolidinediones. Issue 29 (14th July 2020)

• Record Type: Journal Article
• Authors: Cheng, Cheng; Sun, Xiaobin; Miao, Zhiwei
• Is Part Of: Organic & biomolecular chemistry. Volume 18:Issue 29(2020)
• Page Start: 5577
• Page End: 5581
• Publication Date: 2020-07-14
• Subjects: Chemistry, Organic -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1039/d0ob00815j
• Languages: English
• ISSNs: 1477-0520

Abstract

Abstract : An effective strategy for the synthesis of cyclopentane-fused dihydropyrazolone-pyrrolidinediones via a PPh3 -catalyzed sequential annulation reaction of maleimides and unsaturated pyrazolones has been developed. Abstract : A PPh3 -catalyzed sequential cycloaddition of maleimides with unsaturated pyrazolones has been developed. This protocol provides a simple and practical strategy for the construction of dispirocyclopentyl-[dihydropyrazolone-pyrrolidinedione] pyrrolidinedione skeletons containing five contiguous stereogenic centers, including two spiro-quaternary centers, with moderate yields (34–73%) and excellent diastereoselectivities (>20 : 1).