water; zinc T=275°C; 4 h;

n-butyllithium in tetrahydrofuran T=-78°C; Corey-Fuchs reaction;

1.1: n-butyllithium / tetrahydrofuran / -78 °C 1.2: -78 °C 2.1: dicyclohexyl-carbodiimide; 4-(N,N-dimethlyamino)pyridine / dichloromethane / 0 - 20 °C 3.1: acetic anhydride / 140 °C / |Inert atmosphere 4.1: 2,3-dicyano-5,6-dichloro-p-benzoquinone / benzene / 13 h / 80 °C View Scheme

1.1: n-butyllithium / tetrahydrofuran / -78 °C 1.2: -78 - 20 °C 2.1: potassium carbonate / ethanol / 20 °C 3.1: dicyclohexyl-carbodiimide; 4-(N,N-dimethlyamino)pyridine / dichloromethane / 0 - 20 °C 4.1: acetic anhydride / 12 h / 140 °C / |Inert atmosphere View Scheme

n-butyllithium in tetrahydrofuran -78 deg C, 1h, then RT, 1.5 h;

copper(l) iodide; 1,8-diazabicyclo[5.4.0]undec-7-ene in dimethyl sulfoxide T=25°C;

1: 1,1-dibromo-2-(3,4-methylenedioxyphenyl)ethylene With n-butyllithium in tetrahydrofuran T=-78°C; Corey-Fuchs Alkyne Synthesis; 2: formaldehyd in tetrahydrofuran T=-78°C; Corey-Fuchs Alkyne Synthesis;