Photoreaktionen mit Fulleren‐C₆₀ [3 + 2]‐Photocycloaddition von 2,3‐Diphenyl‐2<i>H</i>‐azirin

Abstract

Photoreactions with C 60 ‐Fullerene. [3 + 2] Photocycloaddition of 2,3‐Diphenyl‐2 H ‐azirine Upon irradiation 2,3‐Diphenyl‐2 H ‐azirine ( 2 ) is added to C 60 1 with formation of mono and oligo adducts. 1,9‐(3,4‐Dihydro‐2,5‐diphenyl‐2 H ‐pyrrolo)fulleren‐60 ( 3 ) has been isolated and identified by standard spectroscopic methods. Mechanistic studies revealed two reaction paths leading to 3 , i.e. the classic 1,3‐dipolar cycloaddition via the nitrile ylide 4 (direct irradiation) or a route via 2‐azaallenyl radical cations 5 (sensitization by photoinduced electron transfer).