Novel cyclization of type II biradicals from. alpha.,. beta.-acetylenic ketones
VB Rao, S Wolff, WC Agosta
Index: Rao, V. Bhaskar; Wolff, Steven; Agosta, William C. Journal of the American Chemical Society, 1985 , vol. 107, # 2 p. 521 - 522
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Citation Number: 18
Abstract
There is a good evidence'that the photochemical [3+ 21 cycloaddition between a, P- acetylenic ketones (1) and simple olefins proceeds through reaction of the ketone triplet with olefin to form biradical 2 that then closes to carbene 3. Products are formed from 3 by way of various hydrogen shifts or cyclization to the cy~ lopropene. l-~ Biradical 2 from the excited singlet of 1 closes in the [2+ 21 manner to form alkynyloxetane.'The closure of 2 to 3 ...
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