17257-36-2Relevant academic research and scientific papers
Photochemistry of 1-isopropylcycloalkyl aryl ketones: Ring size effects, medium effects, and asymmetric induction
Xia, Wujiong,Scheffer, John R.,Botoshansky, Mark,Kaftory, Menahem
, p. 1315 - 1318 (2005)
(Chemical Equation Presented) The n = 0, 1, and 2 ketones shown above undergo Yang photocyclization in solution, but only the n = 1 analogues react this way in the solid state. Based on X-ray crystallography, these differences in reactivity are attributed to an unusually large distance for 1,4-hydroxybiradical cyclization in the solid state for the n = 0 and 2 ring systems, which leads to predominant reverse hydrogen transfer (rht). Enantiomeric excesses of up to 99% can be achieved in the case of the n = 1 system through the use of the solid-state ionic chiral auxiliary method of asymmetric synthesis.
Cyclizations of ω-Allenyl Radicals
Apparu, Marcel,Crandall, Jack K.
, p. 2125 - 2130 (2007/10/02)
Allenyl halides of structure (CH3)2C=C=CH(CH2)nX with n=3-6 have been prepared and reacted with n-Bu3SnH to generate the corresponding radicals for examination of the cyclization reactions of these reactive intermediates.The observed hydrocarbon products indicate that cyclization occurs for the n=3,4, and 5 radicals but not for the n=6 species.The n=3 radical isomerizes very efficiently by intramolecular addition to the sp carbon of the allene group.The n=5 intermediate reacts relatively slowly by attack at the near sp2 carbon.Both cyclization modes are observed for the n=4 species.The details of these radical cyclizations are discussed.
