1,1-Cyclobutanedicarboxylic acid → 1-(4-Fluorophenylcarbamoyl)cyclobutanecarboxylic acid

Temperature

0 °C

To a mixture of cyclobutane-1,1-dicarboxylic acid (10.0 g, 69.4 mmol, 1.0 eq.) in anhydrous THF (100 mL) under nitrogen was added dropwise triethylamine (7.02 g, 69.4 mmol, 1.0 eq.) with stirring for 30 minutes at 0° C., followed by the addition of thionyl chloride (8.25 g, 69.4 mmol, 1.0 eq.) with stirring for another 30 minutes at 0° C. To the resulting mixture under nitrogen was added dropwise a solution of 4-fluoroaniline (8.48 g, 76.3 mmol, 1.1 eq.) in anhydrous THF (50 mL) with stirring for 1.5 hours at 0° C. The reaction mixture was diluted with ethyl acetate and extracted with 2N NaOH. The aqueous phase was titrated with 2N HCl to pH 1-2 and then extracted with ethyl acetate. The organic phase was dried with sodium sulfate and concentrated in vacuo to give 1-(4-fluoro-phenylcarbamoyl)-cyclobutanecarboxylic acid as a light pink solid (5.75 g, 34.9%). 1H NMR (400 MHz, CDCl3 w/5 drop CD3OD): 7.53-7.48 (m, 2H), 7.06-7.00 (m, 2H), 2.81-2.63 (m, 4H), 2.14-2.02 (m, 2H).

1. stirringwith stirring for another 30 minutes at 0° C
2. stirringwith stirring for 1.5 hours at 0° C
3. extractionextracted with 2N NaOH
4. extractionextracted with ethyl acetate
5. dry with materialThe organic phase was dried with sodium sulfate
6. concentrationconcentrated in vacuo

ORD record

ord-e8412187c48e45c2a0cbfee1c5515fc7

Source dataset

uspto-grants-2011_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08067436B2