Chlorotrimethylsilane → HCID 18395016, compound

Participants

Reaction Steps

To a suspension of D-tert-leucine (0.250 g., 1.91 mmol, Aldrich) in dichloromethane (3 mL) and DMF (1.5 mL) was added N-methylmorpholine (0.50 mL., 4.55 mmol), followed by chlorotrimethylsilane (0.30 mL., 2.36 mmol) and the mixture stirred at room temperature for 6 hours. Diisopropylethylamine (0.300 mL., 1.72 mmol) was added, followed by 4-(4-chlorophenoxy)benzenesulfonyl chloride (0.636 g., 2.10 mmol, from example 1(c)) portionwise via a solid addition funnel. The resulting solution was then stirred at room temperature for 3.5 hours, and then partitioned between ethyl acetate and 1N aq. sodium bisulfate. The organic layer was washed with brine, dried over MgSO4, and concentrated. The residue was purified on silica gel, eluting with 40% ethyl acetate in hexane followed by 10% methanol in dichloromethane, to give N-[4-(4-chlorophenoxy)benzenesulfonyl]-D-tert-leucine as a white solid in 62% yield: mp 138-140° C.; 1H--NMR (CDCl3) δ 0.949 (s, 9H), 3.51-3.54 (d, 1H, J10.3 Hz), 5.55-5.59 (m, 1H), 6.94-7.83 (m, 8H).

Provenance & Evidence