1: With n-butyllithium; diisopropylamine in tetrahydrofuran; hexane T=-75°C; 1 h; 2: 4-methyl-2-methylsulphanylpyrimidine in tetrahydrofuran; hexane; dichloromethane T=-75°C; 0.5 h; 3: N-methoxy-N-methyl-2,4-dichlorobenzamide in tetrahydrofuran; hexane; dichloromethane T=-75 - 20°C;