Convenient one-pot MCRs to trifluoromethylated spiropiperidine under catalyst-free conditions. Issue 27 (5th July 2018)

• Record Type: Journal Article
• Authors: Zhou, Lu; Yuan, Fangchong; Zhou, Yidi; Duan, Wenwen; Zhang, Min; Deng, Hongmei; Song, Liping
• Is Part Of: Tetrahedron. Volume 74:Issue 27(2018)
• Page Start: 3761
• Page End: 3769
• Publication Date: 2018-07-05
• Subjects: One-pot multi-component reaction -- 1, 2-Diphenylpyrazolidine-3, 5-dione -- Catalyst-free -- Cyclization -- Fluorinated spiropiperidine derivatives; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tet.2018.05.059
• Languages: English
• ISSNs: 0040-4020

Abstract

Abstract: One-pot, four-component reactions of 1, 2-diphenylpyrazolidine-3, 5-dione, ethyl 4, 4, 4-trifluoroacetoacetate, aromatic aldehyde and ammonium acetate afforded highly functionalized ethyl 8-hydroxy-1, 4-dioxo-2, 3, 6, 10-tetraphenyl-8-(trifluoromethyl)-2, 3, 7-triazaspiro[4.5]decane-9-carboxylate derivatives 5 in good yields. The most advantage of this reaction was the high diastereoselectivity because only one diastereoisomer 5 was produced. The effect of NH4 OAc and solvents on the reaction efficiency and yield was briefly investigated. Meanwhile, the further transformation of hemi-aminal moieties to the corresponding dehydrated product was also achieved under the mild reaction conditions. And a plausible reaction mechanism for the formation of products 5 was illustrated based on the control experiments. Graphical abstract: Image 1