N-Methylethylamine → HCID 70654750, compound

To a 0° C. solution of 4-bromo-2-methylbenzenesulfonyl chloride (1.00 g, 3.71 mmol) in CH2Cl2 (10 mL) was added N-ethyldiisopropylamine (0.71 mL, 4.31 mmol) and N-methylethylamine (0.96 mL, 11.13 mmol). The cold bath was removed and the reaction was stirred for 2 h. At completion, the reaction was concentrated, and the crude material was dissolved in CH2Cl2 (20 mL). The mixture was washed with 0.5 N aqueous HCl (3×10 mL), sat. aq. NaHCO3 (2×10 mL), water (10 mL), and saturated aqueous NaCl (5 mL), dried (Na2SO4), and concentrated to give 4-bromo-N-ethyl-2,N-dimethyl-benzenesulfonamide (0.91 g, 3.11 mmol, 85% yield). This material was directly dissolved in 1,4-dioxane (10 mL) and treated with bisboron pinacol ester (0.87 g, 3.43 mmol), PdCl2(dppf)-DCM (69 mg, 0.093 mmol), and KOAc (0.92 g, 9.34 mmol). The reaction was heated at 85° C. for 2 h. At completion, the reaction was cooled to room temperature and concentrated. The crude material was treated with CH2Cl2 (30 mL) and water (10 mL). The organic layer was washed with water (2×10 mL) and brine (5 mL), dried over Na2SO4 and concentrated. The crude material was purified by flash chromatography over silica gel (5-20% EtOAc:hexane eluent) to give N-ethyl-2,N-dimethyl-4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-benzenesulfonamide (0.64 g, 60% yield). 1H NMR (300 MHz, MeOH) δ ppm 7.80-7.88 (m, 1H), 7.68-7.77 (m, 2H), 3.26 (q, J=7.12 Hz, 2H), 2.83 (s, 3H), 2.61 (s, 3H), 1.37 (s, 12H), 1.17 (t, J=7.15 Hz, 3H). MS (EI) m/z: 340 [M+H]+. HPLC (Sunfire C18 4.6 mm×50 mm, 10-90% MeCN:10 mM aq NH4OAc, 2 min gradient) tR=2.48 min, 91% integrated area.

1. customThe cold bath was removed
2. concentrationAt completion, the reaction was concentrated
3. dissolutionthe crude material was dissolved in CH2Cl2 (20 mL)
4. washThe mixture was washed with 0.5 N aqueous HCl (3×10 mL), sat. aq. NaHCO3 (2×10 mL), water (10 mL), and saturated aqueous NaCl (5 mL)
5. dry with materialdried (Na2SO4)
6. concentrationconcentrated

ORD record

ord-690e948e3f3345409e99b87d3d3915a9

Source dataset

uspto-grants-2013_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08440652B2