Conrotatory Photochemical Ring Opening of Alkylcyclobutenes in Solution. A Test of the Hot Ground-State Mechanism
作者:Bruce H. O. Cook、William J. Leigh、Robin Walsh
DOI:10.1021/ja003860o
日期:2001.6.1
and cis- and trans-tricyclo[6.4.0.0(2,7)]dodec-1(2)-ene (cis- and trans-9)-were selected so as to span a broad range in molecular weight and as broad a range as possible in Arrhenius parameters for thermal (ground-state) ringopening. RRKM calculations have been carried out to provide estimates of the rate constants for ground-state ringopening of each of the compounds over a range of thermal energies
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