Photocyclization reactions. Part 8. Synthesis of 2‐quinolone,quinoline and coumarin derivatives using trans‐cis isomerization by photoreaction

2‐Quinolone 2 , quinoline 3 , coumarin (2H‐1‐benzopyran‐ 2 ‐one) 5 , and 2H‐1‐benzopyran hemiacetal 6 were synthesized by photocyclization reaction of traans‐o‐aminocinnamoyl derivatives trans‐ 1 and trans‐o‐hydroxycinnamoyl derivatives trans‐ 4 . The reaction proceeds through trans‐cis isomerization followed by intramolecular cyclization.