1: N,N-dimethyl-formamide With trichlorophosphate T=0 - 20°C; 2: 6-methyl-2-(4-methyl-phenyl)-imidazo[1,2-a]pyridine T=20°C;

[copperl(II)(1,1,1,5,5,5-hexafluoroacetylacetonate)2] monohydrate; oxygen in N,N-dimethyl-formamide T=105°C; 16 h;

1: toluene-4-sulfonic acid / tetrahydrofuran / 18 h / Molecular sieve; Inert atmosphere; Reflux 2: tetrahydrofuran / -78 - 20 °C / Molecular sieve; Inert atmosphere 3: [copperl(II)(1,1,1,5,5,5-hexafluoroacetylacetonate)2] monohydrate; oxygen / N,N-dimethyl-formamide / 16 h / 105 °C View Scheme

1: toluene-4-sulfonic acid / tetrahydrofuran / 18 h / Molecular sieve; Inert atmosphere; Reflux 2: tetrahydrofuran / -78 - 20 °C / Molecular sieve; Inert atmosphere 3: [copperl(II)(1,1,1,5,5,5-hexafluoroacetylacetonate)2] monohydrate; oxygen / N,N-dimethyl-formamide / 16 h / 105 °C View Scheme