Journal
BEILSTEIN JOURNAL OF ORGANIC CHEMISTRY
Volume 9, Issue -, Pages 1083-1092Publisher
BEILSTEIN-INSTITUT
DOI: 10.3762/bjoc.9.120
Keywords
cyclisation; EPR spectroscopy; free radicals; heterocycles; oxime carbonates
Categories
Funding
- EPSRC [EP/I003479/1]
- EaStCHEM
- EPSRC [EP/I003479/1] Funding Source: UKRI
- Engineering and Physical Sciences Research Council [EP/I003479/1] Funding Source: researchfish
Ask authors/readers for more resources
Sensitised photolyses of ethoxycarbonyl oximes of aromatic and heteroaromatic ketones yielded iminyl radicals, which were characterised by EPR spectroscopy. Iminyls with suitably placed arene or heteroarene acceptors underwent cyclisations yielding phenanthridine-type products from ortho-additions. For benzofuran and benzothiophene acceptors, spiro-cyclisation predominated at low temperatures, but thermodynamic control ensured ortho-products, benzofuro- or benzothieno-isoquinolines, formed at higher temperatures. Estimates by steady-state kinetic EPR established that iminyl radical cyclisations onto aromatics took place about an order of magnitude more slowly than prototypical C-centred radicals. The cyclisation energetics were investigated by DFT computations, which gave insights into factors influencing the two cyclisation modes.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available