potassium permanganate in water T=75°C; 2.5 h;

1: With n-butyllithium; 2,2,6,6-tetramethylpiperidinyl-lithium in tetrahydrofuran; hexane T=-78 - 0°C; 2: With 1,2,2-trichloro-1,1,2-trichloro-ethane in tetrahydrofuran; hexane 1 h; Heating; Further stages.;

1.1: 72 percent / lead tetraacetate; iodine; AIBN / CCl4 / 2 h / Heating 2.1: n-butyllithium / tetrahydrofuran; hexane / 2 h / -78 °C 2.2: 65 percent / tetrahydrofuran; hexane / 1 h / 0 °C View Scheme