88 55 84 81 44d 1 6d 86 (ll:89)e 86 (11:89) 87 (11:89) 79 (15:85)' 45d (1436)' "Reaction was conducted by irradiation of a mixture of the sub- strate, nucleophile, phenanthrene (lo%), and p-dicyanobenzene (10%) in acetonitrile with a 200-W high-pressure Hg arc at 20 OC for 10 h. bDetermined by GLC analysis. 'Based on conversion. dThe major byproduct was a 3,4-dihydro-2H-pyran. e The thermodynamic ratio is 40:60. fThe thermodynamic ratio is ...
