1: 1) LDA 2: 1) NaN<Si(CH3)3>2 / 1) xylene, room temp., 2 h, 2) reflux, 4 h 3: 96 percent / H2 / 10percent Pd/C / ethyl acetate 4: 91 percent / diethyl ether / 2 h / Ambient temperature 5: 77 percent / POCl3 / pyridine / 16 h / Ambient temperature 6: 65 percent / H2, PPTS / acetone / Heating View Scheme

T=800°C; P=5E-05 Torr;

selenium(IV) oxide in xylene

sodium hydroxide; Zinc chloride in N,N-dimethyl-formamide

sodium hydroxide; aluminium trichloride in tetrahydrofuran; water

Zinc chloride in nitrobenzene