potassium tert-butylate; tert-butyl alcohol in tetrahydrofuran; N,N,N',N',N'',N''-hexamethylphosphoric triamide T=50°C; 1 h;

1: Te / tetrahydrofuran; hexane / -45 deg C --> 0 deg C 2: 1) tert-butylalcohol; 2) hexamethylphosphoric triamide / 2) 55 deg C, 45 min 3: 90 percent / t-BuOK, t-BuOH / hexamethylphosphoric acid triamide; tetrahydrofuran / 1 h / 50 °C View Scheme

1: 1) BuLi, t-BuOK; 2) LiBr / 1) THF, hexane, -70 deg C, 30 min; 2) -5 deg C 2: Te / tetrahydrofuran; hexane / -45 deg C --> 0 deg C 3: 1) tert-butylalcohol; 2) hexamethylphosphoric triamide / 2) 55 deg C, 45 min 4: 90 percent / t-BuOK, t-BuOH / hexamethylphosphoric acid triamide; tetrahydrofuran / 1 h / 50 °C View Scheme

1: NaTeH / dimethylformamide; ethanol / 1 h / 0 °C 2: KOH / 2 h / 100 °C 3: acetic acid; ethanol / 2 h / Heating View Scheme

in ethanol; acetic acid 2 h; Heating; Yield given;