A slurry of AlCl3 (946 mg, 7.11 mmol) in CH2Cl2 (7 ml) was treated with tert-butylaminoborane (1.24 g, 14.22 mmol) at 0° C. and stirred for 30 minutes. Next, a solution of the product from step e) (671 mg, 2.37 mmol) in CH2Cl2 (5 ml) was added dropwise to the AlCl3/borane solution. After 2 hours at 0° C., the crude reaction mixture was poured into cold 10% HCl, treated with 2 M NaOH to pH 12 and extracted with CH2Cl2 (3×75 ml). The combined organic extracts were washed with brine (75 ml), dried (MgSO4), and solvent evaporated in vacuo leaving the crude product that was purified by silica-gel chromatography using a ethyl acetate/hexanes gradient (0% to 75% ethyl acetate) to give the subtitle compound (409 mg, 64%). MS calculated for C17H19NS+H 270, observed 270.
