2-Benzoylbenzoic Acid → HCID 53808064, compound

Participants

Reaction Conditions

Reaction Steps

6.20 g (27.5 mmol) of o-benzoylbenzoic acid was dissolved in 150 ml of methylene chloride at 25° C. under a nitrogen atmosphere. The solution was cooled to 10° C. and 4.08 g (30.2 mmol) of 1-hydroxybenzotriazole hydrate was added, followed by 5.0 g (30.2 mmol) of L-proline methyl ester HCl and followed by 6.22 g (30.2 mmol) of N,N'-diisopropylethylamine. Lastly, 6.22 g (30.2 mmol) N,N'-dicyclohexylcarbodiimide (DCC) was added which produced a slight exothermic reaction and the mixture was then stirred for 12 hours, after which time tlc analysis indicated complete consumption of starting material. A standard work-up was performed which involved removing precipitated urea by filtration and washing the filtrate with 5% sodium bicarbonate solution, 1N sodium hydroxide solution, 1N hydrochloric acid and brine. The organic phase was dried over magnesium sulfate and evaporated in vacuo to afford a yellow residue. Purification by flash chromatography on silica gel (40:1/methylene chloride:methanol) gave a yield of 6.4 g (69%) of the title compound as a cloudy gum which crystallized on standing. TLC (90:10/CH2Cl2 :MeOH): Rf =0.80. mp=128-130. 1H NMR (CDCl3) δ: 7.40-7.85(m,9H); 4.25-4.55(m,1H); 3.40-3.75(m,5H); 1.85-2.40(m,4H). I.R. (KBr): 1622, 1661, 1739, 1745 cm-1. Standard Combustion Analysis: C,71.20; H,5.68; N,4.15. Found: C,70.63; H,5.53; N=4.36. High Resolution Mass Spectrum: m/e=338.1384±0.8 ppm (calculated for C20H20NO).

Provenance & Evidence