4-Chlorobenzenesulfonyl chloride → Methyl N-(4-chlorobenzene-1-sulfonyl)-L-serinate

A suspension of L-serine-methyl ester hydrochloride (5 g, 32.13 mmol) in CH2Cl2 (100 mL) was added with TEA (1.1 mol eq, 4.9 mL) and the mixture was stirred at r.t. for 10 minutes. Then 4-chlorobenzensulfonyl chloride (1 mol eq, 6.81 g) and additional TEA (1.1 mol eq) were added and the solution hated at 50° C. for 5 h. The solvent was removed under reduced pressure, water was added to the residue (100 mL) and the aqueous phase extracted with EtOAc (3×40 mL). The combined organic phases were dried over Na2SO4 and evaporated to reduced pressure. The residue was recrystallized from ethyl ether to afford 2C as white solid (8.6 g, 91% yield). 1HNMR (DMSO, 200 MHz) δ 3.51 (s, 3H), 3.60 (m, 2H), 3.91 (t, 1H), 5.17 (t, 1H), 7.50 (d, 2H, J=8), 7.89 (d, 2H, J=7.8)), 8.35 (bs, 1H).

1. additionwas added with TEA (1.1 mol eq
2. waitthe solution hated at 50° C. for 5 h
3. customThe solvent was removed under reduced pressure, water
4. additionwas added to the residue (100 mL)
5. extractionthe aqueous phase extracted with EtOAc (3×40 mL)
6. dry with materialThe combined organic phases were dried over Na2SO4
7. customevaporated to reduced pressure
8. customThe residue was recrystallized from ethyl ether

ORD record

ord-e2939cf6d99543a297d97fd53706daaa

Source dataset

uspto-grants-2016_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09409864B2