Photolysis of 11-methylenepentacyclo[5.4.0.02,6.03,10.05,9]undecan-8-spiro-3′-diazirine.: Medium dependent reaction

11-Methylenepentacyclo[5.4.0.0(2,6). 0(3,10).0(5,9)]undecan-8-spiro-3'-diazirine (1) has been synthesized and its photochemical decomposition in different media has been investigated. Irradiation of Nz-purged benzene solution of diazirine 1 produced a mixture of four azine-isomers 7a-d. However, photolysis of 1 in pentane gave a mixture of hydrocarbons 6 as the main insertion products and traces of 1,3-bishomopentaprismane (5). The photolytic decomposition of 1 in N-2-matrix at -196 degrees C proved the formation of diazo-compound 8, which upon warm-up gave traces of 1,3-bishomopentaprismane (5).