Scheme 106. Synthesis of Thiophene-Fused Perylenoids Through Dehydrogenative Photocyclizations.

Reagents and conditions: (a)²¹³ Ac₂O, Et₃N, THF, reflux, 16 h, then 1-bromopropane, DBU, 1:10 PrOH/THF, reflux, 10 h, 53%; (b) I₂, 1:13 dioxane/toluene, hν (incandescent lamp), reflux, 6 days, 75%; (c) amine hydrochloride, imidazole, o-dichlorobenzene, reflux, 16 h, 33–40%; (d)²¹⁴ Na₂CO₃, 77:1 acetone/H₂O, rt, hν (medium pressure mercury lamp), 5 h, 21%.