A new photoinduced rearrangement of steroidal α,β-unsaturated cyclic ketone oximes into the β,γ-unsaturated isomer involving an intramolecular stereospecific hydrogen transfer
作者:Hiroshi Suginome、Takashi Ohki
DOI:10.1039/c39880001568
日期:——
aprotic solvent gave rise to 4,4-dimethyl-1-methylene-5α-cholestan-3-one oxime in 69–75% yield; mechanism for this photo-isomerization which involves an intramolecular stereospecific transfer of a hydroxyimino hydrogen is proposed on the basis of deuterium labelling studies.
Photoinduced molecular transformations. Part 133. New photoinduced deconjugation of steroidal α,β-unsaturated cyclic ketone oxime into the β,γ-unsaturated isomer involving stereospecific proton transfer
photo-Beckmann rearrangement was formed. Deuterium-labelling studies on the photoreactions of 1-methyl-5α-cholest-1-en-3-one oxime established that either a proton or a deuteron is stereospecifically introduced at the 2α-position of the steroidal oxime in this photodeconjugation. A pathway which involves the sterospecific addition of either a proton or deuteron to the photogenerated, twisted double bond of