Copper-Mediated [3+2] Annulation of 3-N-Hydroxyallylamines with Nitrosoarenes

• Published in: Chemistry : a European journal Vol. 22; no. 9; pp. 2915 - 2919
• Main Authors: Ghorpade, Satish, Jadhav, Prakash D., Liu, Rai-Shung
• Format: Journal Article
• Language: English
• Published: Germany Blackwell Publishing Ltd 24-02-2016; Wiley Subscription Services, Inc
• Subjects: annulation; Chemical reactions; Chemistry; Copper; Cycloaddition; N-Oxides; nitrosoarenes; Organic chemistry; oxidants; Oxides; Quinoline; Radicals; Utilities; nitrosoarenes; copper; oxidants; annulation; radicals
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.201504784

Cu‐mediated annulations of N‐hydroxyallylamines with nitrosoarenes proceed through unprecedented formal [3+2] cycloadditions of N‐hydroxyaminoallyl radicals with nitrosoarenes. Our mechanistic analysis opposes a 5‐endo‐trig cyclization involved in the final ring‐closure step. To manifest the reaction utility, chemical elaborations of resulting isoxazolidinyl products into 2‐ or 3‐substituted quinoline N‐oxides and acyclic 1,3‐diamino‐2‐ols are also described.
Radical initiative! Cu‐mediated annulations of N‐hydroxyallylamines with nitrosoarenes proceed through unprecedented formal [3+2] cycloaddition reactions (see scheme). To manifest the reaction utility, chemical elaborations of resulting isoxazolidinyl products into 2‐ or 3‐substituted quinoline N‐oxides and acyclic 1,3‐diamino‐2‐ols have been described.