“…Several methods with different catalysts have been published, among others CuCl [9], CuI [10] or CuBr 2 [11] and TEMPO, Ru-complex [12,13], Au powder [14,15], gold supported on alumina [15], magnetic gold nanoparticles [16], Au-Pd nanoparticles [17], Fe/CCl 4 [18], Co-porphyrin complex [19], the heteropolyacid NPV 6 Mo 6 [20], VO(Hhpic) 2 [21] under aerobic conditions, V 2 O 5 /H 2 O 2 [22], AIBN and oxygen [23], TiO 2 as photocatalyst [24][25][26], or TBHBQ [27] have been described. Several other metals were also used in photocatalytic reactions [28].…”