lithium hexamethyldisilazane; tris-(dibenzylideneacetone)dipalladium(0); 2-dicyclohexylphosphino-2',4',6'-tri-1-propyl-1,1'-biphenyl in tetrahydrofuran T=65°C; 0.5 h;

trifluoroacetic acid in dichloromethane 48 h; Reflux;

1.1: sodium hydride / N,N-dimethyl-formamide / 0.5 h / 0 - 20 °C 1.2: 15 h / 100 °C 2.1: p-toluenesulfonyl chloride / dichloromethane / 1.67 h / 0 - 20 °C 3.1: trifluoroacetic acid / dichloromethane / 48 h / |Reflux View Scheme

1.1: sodium hydride / N,N-dimethyl-formamide / 0.5 h / 0 - 20 °C 1.2: 15 h / 100 °C 2.1: p-toluenesulfonyl chloride / dichloromethane / 1.67 h / 0 - 20 °C 3.1: trifluoroacetic acid / dichloromethane / 48 h / |Reflux View Scheme

1: p-toluenesulfonyl chloride / dichloromethane / 1.67 h / 0 - 20 °C 2: trifluoroacetic acid / dichloromethane / 48 h / |Reflux View Scheme