Scheme 5. The (a) proposed mechanism of spiroindolinepyridoindolone C conversion to C-allylspiroindolinepyridoindoledione Dvia a Claisen rearrangement (
) or radical mechanism (
) and (b) mechanistic investigation of C-allylspiroindolinepyridoindoledione 33a–b formation. ^ presence of some grease in sample.
