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Selectivity in the lactone formation via CH insertion reaction of diazomalonates

✍ Scribed by Lee Eun; Woon Jung Kyung; Seong Kim Yong

Book ID
104226518
Publisher
Elsevier Science
Year
1990
Tongue
French
Weight
274 KB
Volume
31
Category
Article
ISSN
0040-4039

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✦ Synopsis

Rhodium(II)-acetate mediated intramolecular C-H insertion reactions of alkyl methyl diazomalonates result in the formation of /3-and +ctones.

The selectivity depends on both the substitution pattern of insertion centers and the conformational bias of metallocarbenes. Intramolecular C-H insertion reaction& are unique in the formation of ring systems in that unactivated carbon centers are utilized in annulations. Preferred formation of five-membered ring carbocycles from methyl esters of o-diazo-pketo carboxylic acids is well documented2. Four-membered ring ,&lactams are apparently the favored products from the C-H insertion reactions of various a-diazoacetoacetic amides3. Despite scattered examples4 of successful application of the C-H insertion

📜 SIMILAR VOLUMES

Rhodium catalysed reactions of silylated
Rhodium catalysed reactions of silylated diazoacetates: Stereoselective synthesis of α-silylated γ-lactones via CH insertion
✍ Stephen P Marsden; Wai-Kit Pang 📂 Article 📅 1998 🏛 Elsevier Science 🌐 French ⚖ 257 KB

The rhodium catalysed C-H insertion reactions of o~-(triethylsilyl)diazoacetates have been studied, facilitating the stereoselective synthesis of t~-(triethylsilyl)-y-lactones. An intriguing 'and unprecedented inversion of stereoselectivity is observed upon changing from rhodium (It) carboxylates to