Naslov
Photoinduced Intramolecular formal [4 + 2] Cycloaddition of Aryl-Substituted o-Vinylstyryl-2-oxazoles To Form Benzo[f]quinoline Derivatives: Experimental Results and Theoretical Interpretation

Autori
Šagud, Ivana ; Antol, Ivana ; Marinić, Željko ; Šindler-Kulyk, Marija

Izvornik
The Journal of Organic Chemistry (0022-3263) 80 (2015); 9535-9541

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
molecular modeling; oxazoles; photochemistry; photocyclization; synthesis; TD-DFT calculations

Sažetak
A new approach to benzo[f]quinoline derivatives has been found by effective formal [4+2] photocycloaddition process from novel aryl substituted o-vinylstyryl-2-oxazoles. All of the o-vinylstyryl-2-oxazoles were synthesized by multicomponent Wittig reaction from diphosphonium salt of a, a’-o-xylenedibromide, formaldehyde and 5-tolyl-, 4-phenyl-5-methyl- and 4, 5-diphenyloxazole-2-carbaldehydes. TD-DFT calculations revealed that the intramolecular photocyclization in 2-(2-vinylstyryl)oxazoles to form benzo[f]quinoline derivatives proceeds on the S1 PES via stepwise pathway, namely by 10p followed by 6p ring closure. On that path the existence of a S0/S1 conical intersection was indicated. The reactivity of the photocyclization steps depends on the substitution pattern at the positions 4 and 5 of the oxazole ring where the aryl group in position 5 deactivates the reaction.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

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