Cyclobutene Photochemistry. Steric Effects on the Photochemical Ring Opening of Alkylcyclobutenes
作者:William J. Leigh、J. Alberto Postigo
DOI:10.1021/ja00111a004
日期:1995.2
total quantum yield for ringopening increases to a maximum of -0.3 and then decreases with further methyl substitution. The quantum yields for ringopening (t q5tod for the cis-isomer is significantly lower, but both yield an approximate 1:l mixture of formally allowed and forbidden diene isomers. A similar trend is observed in the relative quantum yields for ringopening and cycloreversion throughout