Strained organic molecules. I. 1,5,6-Triphenyltricyclo[3.1.0.02,6]hexan-3-one

Addition to Alkenes

“…In the homologous series [85], only copper catalysis afforded tricyclo[2.1.1.0 ]hexane derivatives [86], whereas photolysis and silver catalysis led to Wolff rearrangement(637)(638)(639). 3-Diazomethylketocyclopropenes [83] are the only unsaturated diazoketones known so far where both light (634, 635) and copper catalysis (636) effected intramolecular addition to produce the tricyclo[1.1.1.0 ]pentane skeleton [84].…”