“…When Lewis acids (AlCl 3 or ZnCl 2 ) are used, trace amounts of thienopyrimidines 94 were also found among the reaction products 169. The lat-ter are products of the competing tandem Pinner-Dimroth reaction and subsequent photooxidation and become the major reaction products under EtONa catalysis (Scheme 38).In the Friedländer reaction with Gewald´s thiophenes β-ketophosphonates,170,171 heterocyclic ketones and 1,3-diketones, 172 methylene active nitriles (under basic catalysis conditions), 173,174 and -haloketones 175 can react instead of ketones or ethyl acetoacetate.…”