Synthesis
Step 2: Synthesis of 2-(4-chlorophenyl)-2-oxoacetic acid
Ethyl 2-(4-chlorophenyl)-2-oxoacetate (4.0 g, 18.9 mmol) was reacted with lithium hydroxide (1.98 g, 47.1 mmol) in a solvent mixture of THF:MeOH:H2O (76 mL, v/v 10:6:3) with stirring for 3 h at 25 °C. The reaction was carried out at 25 °C for 2 h. The reaction was carried out at 25 °C for 3 h. The reaction was completed with the use of concentrated hydrochloric acid. Upon completion of the reaction, the mixture was neutralized to pH 2-3 with concentrated hydrochloric acid. the resulting white precipitate was collected by filtration, washed three times with water and dried under vacuum to afford (4-chlorophenyl)glyoxalic acid (3.0 g, 86% yield) as a white solid. Mass spectrometry (electrospray positive ion mode) analysis showed that the theoretical mass-to-charge ratio of C8H5ClO3 was 184,186; the measured value was 185,187 [M + H]+.
References
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[4] Patent: EP1486483, 2004, A1. Location in patent: Page 32
[5] Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 2013, vol. 52, # 6, p. 818 - 823
