UV-laser photochemistry: Generation of the triplet spiro[2.6]nona-4,7-diyl diradical by nitrogen extrusion from the azoalkane 6,7-diazaspiro[bicyclo (3.2.2)non-6-ene-2,1′-cyclopropane]. Conformational influence on the lifetime of a 1,4-cycloheptadiyl as determined by the cyclopropylcarbinyl “free radical clock”
作者:Waldemar Adam、Sven Grabowski、Frank Scherhag
DOI:10.1016/s0040-4039(00)80832-1
日期:1988.1
Using the cyclopropylcarbinyl rearrangement, the lifetime of the tripletdiradical spiro[2.6]nona-4,7-diyl was estimated as 0.3 < 3τ < 3.3 ns; the short tripletlifetime of this localized 1,4-diradical is rationalized in terms of fast ISC out of its initial boat or twistboat conformation.