1: 2,4,6-Trichloropyridine With n-butyllithium in tetrahydrofuran; hexane T=-78°C; 1 h; 2: carbon dioxide in tetrahydrofuran; hexane T=-78 - 0°C;

1.1: trichlorophosphate / 6 h / 100 °C 1.2: pH 8 - 9 / Cooling with ice 2.1: diisopropylamine; n-butyllithium / hexane; tetrahydrofuran / 1.5 h 2.2: 1 h / 20 °C View Scheme

1.1: trifluoroacetic acid; dihydrogen peroxide / 6 h / 100 °C 2.1: trichlorophosphate / 6 h / 100 °C 2.2: pH 8 - 9 / Cooling with ice 3.1: diisopropylamine; n-butyllithium / hexane; tetrahydrofuran / 1.5 h 3.2: 1 h / 20 °C View Scheme