The case of the missing acetylene. The mechanism of an intramolecular S-N(V) reaction and a new route to 1-methylbenzo[de]quinolines

Hodgson, D.R.W.; Kirby, A.J.; Feeder, N.

Abstract

1-Halogeno-2-(1-naphthyl)alkenes with a dimethylamino group in the peri position are smoothly converted to 1-methylbenzo[de]quinoline under mild conditions, in a process involving the loss of MeBr rather than HBr. The Z-bromide is 45 times more reactive than its E-isomer, and 7 times more reactive than the Z-chloride. These systems were designed to show efficient elimination of HBr, but acetylene is not a likely intermediate. There is good evidence to support both of two alternative addition–elimination mechanisms: a 6-endo-dig route which would involve a “normal” addition–elimination process in an unusual setting; and a tandem 5-exo-dig Michael addition–carbene rearrangement. The evidence so far does not permit a final choice between the two.

Citation

Hodgson, D., Kirby, A., & Feeder, N. (1999). The case of the missing acetylene. The mechanism of an intramolecular S-N(V) reaction and a new route to 1-methylbenzo[de]quinolines. Journal of the Chemical Society. Perkin transactions 1, 949-954. https://doi.org/10.1039/a900090i

• Journal Article Type: Article
• Acceptance Date: Feb 15, 1999
• Publication Date: 1999
• Deposit Date: May 6, 2015
• Journal: Journal of the Chemical Society, Perkin Transactions 1
• Print ISSN: 1472-7781
• Electronic ISSN: 1364-5463
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Issue: 8
• Pages: 949-954
• DOI: https://doi.org/10.1039/a900090i
• Public URL: https://durham-repository.worktribe.com/output/1429861