3-Aminobenzoic Acid → 3-({[2-(Ethoxycarbonyl)ethyl]amino}carbonylamino)benzoic acid

A solution of 3-amino benzoic acid (5.0 g, 36.5 mmol) in THF (250 ml)/DCM (250 ml) was cooled to 0° C. and treated with triphosgene (3.79 g, 12.76 mmol) followed by TEA (12.70 ml, 91 mmol). After 5 min, a suspension of beta-alanine ethyl ester hydrochloride (11.20 g, 72.9 mmol) and TEA (12.70 ml, 91.00 mmol) in THF (10 ml)/DCM (10 ml) were added and the resulting mixture was allowed to warm to RT and stirred overnight. The reaction mixture was diluted with DCM (100 ml) and the pH was adjusted to 8 by addition of sat. aq. NaHCO3. The mixture was extracted with water (2×250 ml). The combined aqueous extracts were acidified to pH 1 by addition of 2N HCl, extracted with DCM and the combined organic portions were washed with brine, dried over MgSO4 and concentrated in vacuo to afford the title product as an off-white solid; LC-MS Rt 0.84 mins; 281.2 [M+H]+, Method 2minLC_v003.

1. additionwere added
2. extractionThe mixture was extracted with water (2×250 ml)
3. additionThe combined aqueous extracts were acidified to pH 1 by addition of 2N HCl
4. extractionextracted with DCM
5. washthe combined organic portions were washed with brine
6. dry with materialdried over MgSO4
7. concentrationconcentrated in vacuo

ORD record

ord-5448d5147d6846369b5ae08ef223157c

Source dataset

uspto-grants-2013_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08372845B2