Abstract
Abstract Naphthalene was carboxylated to naphthoic acids by the irradiation of naphthalene and a donor in the presence of carbon dioxide. The UV irradiation through Pyrex caused reactions of naphthalene, itself, giving a naphthalene dimer etc. Such undesirable reactions were partly depressed by using a CuSO4 filter solution; the selectivities of naphthoic acids and dihydronaphthalenecarboxylic acid increased from 2.2–9.8 to 12.2–23.0%. To avoid any direct irradiation to naphthalene and naphthoic acids was critical. Their high selectivities, up to 67%, were obtained upon visible light irradiation by using phenazine as a sensitizer. More than 90% of the naphthoic acids was 1-naphthoic acid, which was confirmed by GC and ms.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have