ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Gold-catalyzed cyclization of unconjugated ynone derivatives for 2H-1,2-oxazine and 1-hydroxypyrrole skeletons through one-pot and single-step strategy

Volkan Taşdemir and Nurettin Menges

Muradiye Vocational School, Van Yüzüncü Yıl University, Van, Turkey

E-mail: nurettin.menges@erbakan.edu.tr

Received: 3 January 2023  Accepted: 16 August 2023

Abstract:

Unconjugated ynone derivatives with the 1,3-dicarbonyl structure are synthesized, and they are directly subjected to gold-catalyzed reaction with hydroxylamine without obtaining the oxime derivative. Among the different metal salts investigated, AuCl₃ is the best for yielding and obtaining two different heterocyclic skeletons. Thanks to this reaction, two important heterocyclic molecules, 2H-1,2-oxazine and 1-hydroxypyrrole, are obtained as a one-pot and single-step strategy with favorable yields. Eleven different 2H-1,2-oxazine and 6 different 1-hydroxypyrrole derivatives are synthesized using starting compounds containing different substituents, in which steric hindrance and electronic effect are also taken into account. When the same reaction is carried out with the unconjugated ynone derivative containing only one carbonyl group, the only 1-hydroxypyrrole derivative is observed to be formed, and 1,2-oxazine ring is not observed.

Graphical abstract

Keywords: Alkyne cyclization; Homogen catalysis; Heterocyclic chemistry; One-pot reaction

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-023-03041-6

Chemical Papers 77 (12) 7985–7992 (2023)