81920-63-0Relevant academic research and scientific papers
Photoinduced Transformations. Part 60. Photoinduced Rearrangements of Cholesteryl Nitrites with Monochromatic Light
Suginome, Hiroshi,Maeda, Norio,Kaji, Makoto
, p. 111 - 116 (2007/10/02)
Photolysis of cholesteryl nitrite in benzene with monochromatic light (λ 389 nm) gave (E)-4'-azodi-(3,4-secocholest-5-en-3-one) N,N'-dioxide (9) which transformed into N-hydroxy-4-aza-4a-homocholest-5-en-3-one (10) and 3,3-bisisopropoxy-3,4-secocholest-5-en-4-one oxime (20) in isopropyl alcohol under reflux.Photolysis of the dimer (9) with Pyrex-filtered light gave 3,4-secocholest-5-ene-3,4-dione 4-oxime (25).In contrast, irradiation of 4,4-dimethylcholesteryl nitrite (2) in benzene with monochromatic light gave a good yield of 4a,4a-dimethyl-4-aza-4a-homocholest-5-en-3-one (11) without any accompanying nitroso-dimers.These results as evidence that hydroxamic acids obtained from the photolysis of nitrites are formed by thermal cyclization of nitrosointermediates .Although irradiation of the nitrite (2) with Pyrex-filtered light gave a result similar to that with monochromatic light, low yields of the Z-isomer (26) of the nitroso-dimer (9) and 3β(4-oxa-4a-homocholest-5-en-3α-yloxy)cholest-5-ene (27) were isolated from a mixture obtained from the photolysis of cholesteryl nitrite (1) with Pyrex-filtered light.Some notable features in the present results are discussed.
