Sequential 1, 4‐/1, 2‐Addition of Lithium(trimethylsilyl)diazomethane onto Cyclic Enones to Induce C−C Fragmentation and N−Li Insertion. (22nd December 2015)

• Record Type: Journal Article
• Authors: O'Connor, Matthew J.; Sun, Chunrui; Guan, Xinyu; Sabbasani, Venkata R.; Lee, Daesung
• Is Part Of: Angewandte Chemie. Volume 128:Number 6(2016)
• Page Start: 2262
• Page End: 2265
• Publication Date: 2015-12-22
• Subjects: Carbene -- C-C-Bindungsspaltung -- 1, 3-Dipolare Cycloadditionen -- Pyrazole -- α, β-Ungesättigte Ketone; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201510152
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: α, β‐Unsaturated ketones generally undergo addition reactions with nucleophiles with a preference for either 1, 2‐ or 1, 4‐addition, but rarely both. However, the right combination of reagents allows for consecutive 1, 4‐ and 1, 2‐additions to occur: Cyclic α, β‐unsaturated ketones undergo double additions with lithium(trimethylsilyl)diazomethane, effectively generating various molecular frameworks with complexity and diversity. Owing to the sequential generation of several intermediates of multifaceted reactivity, including diazoalkane derivatives and alkylidene carbenes, it is possible to induce novel Grob‐type C−C fragmentations, alkylidene carbene mediated Li−N insertions, and dipolar cycloadditions by controlling the reaction parameters.