2,3-DIHYDR0-7H-DIBENZO [de, h]QUINOLINESrespectively. No unreacted aziridine could be detected after these prolonged reactions at high temperature.Reversibility of the Thermal Valence Isomerization of 1-Cyclohexyl-6-(cyclohexylimino)-la-phenylindano [ 1,241 aziridine. A. Reaction in the Absence of Dipo1arophile.-A deoxygenated solution of 1.15 g (3 mmol) of 4 in 30 ml of toluene was heated to 135-145" for 24 hr giving a deep red color. Evaporation of the solvent and trituration of the residue with ethanol gave recovered indano[l,2-6] aziridine 4 as a slightly yellow solid, mp 158-159", 0.702 g (6lY0 recovery). Evaporation of the ethanol mother liquor afforded 0.068 g (19'%) of 28, 123-124".B. Parallel Reaction in the Presence of a Dipolarophi1e.-A similar experiment was performed with 1.5 g (3 mmol) of 4 and 0.519 g (3 mmol) of N-phenylmaleimide under exactly comparable conditions and resulted in the isolation of adduct 6 (see above), 1.34 g (8O' %), mp 235-236", but no aziridine 4 could be recovered.Reversibility of Photochemical Valence Isomerization of 1-Cyclohexyl-6-(6-cyclohexylimino)-la-phenylindano [ 1,241 aziridine -A solution of 1.063 g (2.8 mmol) of the indano[l,2-b]aziridine 4 in 100 ml of tetrahydrofuran was irradiated under nitrogen a t 0 to -10" in a quartz cell using a 450-W Hanovia high-pressure lamp for 8 hr. A deep red solution was obtainedz4 and when exposed to visible light the color rapidly faded to a pale yellow resulting in a virtually complete restoration of the infrared absorption spectrum of the original compound 4.Photochemical Reaction between l-Cyclohexyl-6-(cyclohexylimino)-la-phenylindano [ 1,2-b] aziridine and Cyclohexylamine Hydrobromide.-A mixture of 1.15 g (3 mmol) of the indano[l,2-b]-aziridine 4 and 1.08 g (6 mmol) of cyclohexylamine hydrobromide in 150 ml of ether and 20 ml of methanol was irradiated for 8 hr under nitrogen with a 450-W high-pressure Hanovia lamp in a quartz reaction vessel. The resulting yellow solid 29 was colected and recrystallized from ether-methanol, 0.527 g (38%): mp 298-299"; ir (CHC13) 1617 (C=N), 3230 cm-l (NH); nmr (24) The very close similarity of the absorption spectrum of this species [Amax (dioxane) 500 mN, 520 (sh), 565 (ah)] to that obtained by heating 4 [Amax (xylene) 505 mN, 534 (ah), and 570 (ah) ] may be noted. ~T M B (CDCla) 0. 20, CeHl,), 3.0-3.6 (m, 1, CHNHC=), 3.9-4.5 (m, 1, =N+CH), 6. 9, aromatic protons), 8.51 (d, 1, D2O exchangeable XH), 9.65 (d, 1, J = 7 Hz, aromatic protons); uvmax (95'3$ EtOH-HBr) 393 mp (log e 4-12), 335 (3.77), 324 (sh, 3.72), 288 (3.86), 279 (3.89); mass spectrum (70 eV) 384.Anal. Calcd for C2,Ha3N2Br: N, 6.02. Found: N, 5.56. The identical compound was obtained by heating the indano-[ 1,241 aziridine with cyclohexylamine hydrobromide or ammonium bromide in toluene.Photochemical Reaction between l-Cyclohexyl-6-(cyclohexylimino)-la-phenylindano [ 1,241 aziridine and cis-1 ,Z-Dichloromethylene.-A mixture of 1.15 g (3 mmol) of the indano[l,2-b]-aziridine 4 and 20 ml of cis-1,2-dichloroethylene in 100 ml of ...