Photochemical transformation of N-(p-toluenesulfonyl)diphenylcyclopropenimine

✍ Scribed by Naruyoshi Obata; Akihiko Hamada; Takeo Takizawa

• Publisher: Elsevier Science
• Year: 1969
• Tongue: French
• Weight: 200 KB
• Volume: 10
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)88546-4

✦ Synopsis

There have been reported some interesting results on the photochemical transformations of cyclopropene derivatives: 3-acyl-1,2-diphenylcyclopropene (1) and 1,3,3-trimethylcyclopropene (21, dergoes dimerisations at the strained double bond while diphenylcyclopropenone takes a route ofa-cleavage to the formation of a quantitative amount of diphenylacetylene (3) . You we wish to report other types of the photochemicsl conversion of a cyclopropene derivative. Irradiation of N-(p_toluenesul.fonyl)diphenylcyclopropenimine (I)(4) in dry benaene under a nitrogen stream by a nigh pressure mercury lamp for 4 hours resulted in the formations of the following products: diphenjlacetylene (5a) (II, 45 $), l-cyano-2-J-toluenesulfonyl-a-stilbene (III, mp 165-165.5'. 5 $), 9cyano-lo-I-toluenesulfonylynenanthrene (IV, mp 226-227'. 3 $), 9,10-dicyanophenanthrene(5b) (V, mp 290-291', 8$), _p-toluenesulfonylafiide(5c) (VI, mp 137', lj $), and p-tolyl p-toluenetiolsulfonate (5d) (VII, mp 75-75.5". 7 $). The -structures of II, V, VI and VII were firmely established by comparisons with authentic samples (5a-d) . The compounds III and IV showed s:ltisfactory elemental analyses and molecular weight determinations as those expected from CZ>H,~NSO~ znd CI~H, sNS02, respectively. In their IR spectra, there was observed characteristic absorptions of CsN (at 2220 cm -' for III and 2215 cm-) for IV) and SO,-group (at 1150 cm+ for both compounds). The results indic:ate that there are a cyano group snd ltoluenesulfonyl group in these compounds. The cis-stilbene structure for III and phenanthrene for IV are clearly shown by their UV and NiW spectra. The