A new octahydroquinoxaline system via the intramolecular addition of a secondary amine to an isolated triple bond. A novel heterocyclization reaction.

✍ Scribed by Jacob Szmuszkovicz; John H. Musser; L.G. Laurian

• Publisher: Elsevier Science
• Year: 1978
• Tongue: French
• Weight: 251 KB
• Volume: 19
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)85371-5

✦ Synopsis

In the course of our search for biologically active agents, we discovered a novel heterocyclizatinn reaction. We wish to report details of the reaction and then comment on possible mechanisms implicated in the cyclization.

When an aqueous solution of 7-methyl-7-azabicycloL4.l.O]heptane (1) and 2 eq of Nmethylpropargylamine (2) was heated at reflux temperature overnight with a trace of ammonium chloride, 2 the expected N,N'-dimethyl-N-2-propynyl-1,2-cyclohexanediamine 1 was not obtained.

Instead, 1,4,4a6,5,6,7,8,8a~~_octahydr~l,2,4_trimethylquinoxaline (k) was isolated as a pale yellow oil in 50% yield, after fractional distillation (BP 68710, 0.3 mm) of the crude reaction mixture.