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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1442886Generated: October 31, 2026

3-Acetamidophthalic Anhydride → Apremilast, (+-)-

https://huagongshe.com/reaction/1442886

Reaction equation

Participants

RoleNameHCIDCharge
Reactant3-Acetamidophthalic AnhydrideHCID 226121—
Reactant1-(3-Ethoxy-4-methoxy-phenyl)-2-methanesulfonyl-ethylamineHCID 11288792—
SolventAcetic AcidHCID 176—
ProductApremilast, (+-)-HCID 1015171559.3%

Reaction Steps

A stirred solution of 1-(3-ethoxy-4-methoxyphenyl) -2-methylsulfonylethylamine (1.0 g, 3.7 mmol) and 3-acetamidophthalic anhydride (751 mg, 3.66 mmol) in acetic acid (20 mL) was heated at reflux for 15 h. The solvent was removed in vacuo to yield an oil. Chromatography of the resulting oil yielded the product as a yellow solid (1.0 g, 59% yield): mp, 144° C.; 1H NMR (CDCl3) δ1.47 (t, J=7.0 Hz, 3H, CH3), 2.26 (s, 3H, CH3), 2.88 (s,3H, CH3), 3.75 (dd, J=4.4, 14.3 Hz, 1H, CHH), 3.85 (s, 3H, CH3), 4.11 (q, J=7 Hz, 2H, CH2), 5.87 (dd, J=4.3, 10.5 Hz, 1H, NCH), 6.82-6.86 (m, 1H, Ar), 7.09-7.11 (m, 2H, Ar), 7.47 (d, J=7 Hz, 1H, Ar), 7.64 (t, J=8 Hz, 1H, Ar), 8.74 (d, J=8 Hz, 1H, Ar), 9.49 (br s, 1H, NH); 13C NMR (CDCl3) δ14.61, 24.85, 41.54, 48.44, 54.34, 55.85, 64.43, 111.37, 112.34, 115.04, 118.11, 120.21, 124.85, 129.17, 130.96, 136.01, 137.52, 148.54, 149.65, 167.38, 169.09, 169.40; Anal Calc'd. for C22H24NO7S: C, 57.38; H, 5.25; N, 6.08. Found: C, 57.31; H, 5.34; N, 5.83.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS07659303B2
Source datasetuspto-grants-2010_02
ORD IDord-cfd3787f868147faaf7e4b0eb737dd7c
Source noteuspto-grants-2010_02