methyl 2-methylpropane-2-sulfinate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: (S)-N-((R)-4-(3,4-Dichlorophenyl)butan-2-yl)-2-methylpropane-2-sulfinamide (600 mg, 1.862 mmol) was stirred in MeOH (10 mL) at rt. 4N HCl in dioxane (5 mL) was added. The resulting mixture was stirred at rt for 20 min. The solvents were evaporated and CH2Cl2 (3×) was added and evaporated. The resulting white solids were vacuum dried for 5 h to give (R)-4-(3,4-dichlorophenyl)butan-2-amine hydrochloride (462 mg, 1.815 mmol, 97% yield) as off-white solids and methyl 2-methylpropane-2-sulfinate. The HCl salt was used without further purification. LC-MS (ESI) m/z 218.0 (M+H), RT=1.61 min (Method B). The solvents were evaporated CH2Cl2 (3×) was added evaporated dried for 5 h

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Intermediate 15B (370 mg, 1.21 mmol) was stirred in MeOH (5 mL) at rt. 4N HCl in dioxane (2 mL) was added. The resulting mixture was stirred at rt for 20 min. The solvents were evaporated and CH2Cl2 (3×) was added and evaporated. The resulting white solids were vacuum dried for 1 h to give Intermediate 15 (84 mg, 0.35 mmol, 29% yield) and methyl 2-methylpropane-2-sulfinate. The HCl salt was used directly in the next step. 1H NMR (400 MHz, MeOD) δ ppm 7.57 (1 H, d, J=7.8 Hz), 7.47 (1 H, d, J=7.6 Hz), 7.25 (1 H, t, J=7.8 Hz), 4.88 (1 H, dd, J=7.8, 4.8 Hz), 3.09-3.23 (1 H, m), 2.90-3.08 (1 H, m), 2.64 (1 H, dddd, J=14.1, 8.5, 8.3, 5.7 Hz), 2.01-2.23 (1 H, m, J=14.1, 8.7, 5.3, 5.3 Hz). The solvents were evaporated CH2Cl2 (3×) was added evaporated dried for 1 h