potassium tert-butylate; tert-butyl alcohol

1: KOtBu, <18>-crown-6 / benzene 2: 1) t-BuLi / 2) -78 deg C up to 25 deg C, 12 h 3: 70 percent / KOH, <18>-crown-6 / benzene / 24 h / Ambient temperature; other phosphinotolanes 4: 1) dioxane*Br2 / 1) CHCl3 View Scheme

1: KOtBu, tBuOH 2: (i) nBuLi, (ii) B(OnBu)3 3: aq. H2O2 / acetic acid; ethanol View Scheme