Making APIs and fine chemicals with light

Very few industrial synthetic processes are based on visible light photochemical processes including the low-cost synthesis of rose oxide, and the production of the anthelmintic drug ascaridole via solar irradiation of alpha-terpinene carried out since 1943. Even more, the high cost of light due to the poor efficiency of most electric light sources (until the advent of LEDs in the early 2000s) discouraged chemical companies from introducing light photons as chemical reagents, no matter how clean they could be.