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A mixture of 2-(4-nitrophenyl)propanoic acid (15.0 g, 76.9 mmol), dimethylaminopyridine (4.70 g, 38.4 mmol) and tert-butanol (8.10 mL, 84.6 mmol) in methylene chloride (300 mL) was stirred at 0° C. for 2 h. After this time, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (17.0 g, 84.6 mmol) was added and the reaction stirred for a further 2 h. The ice bath was then removed and the reaction left to stir at room temperature overnight. After this time, the solvents were concentrated under reduced pressure and the solids redissolved in ethyl acetate (200 mL). The organic layer was then washed with saturated sodium bicarbonate (200 mL), 1 M citric acid (200 mL) and brine (200 mL), dried over magnesium sulfate, filtered, and concentrated under reduced pressure. Purification by flash chromatography (silica, 1:20 ethyl acetate/hexanes) afforded tert-butyl 2-(4-nitrophenyl)propanoate (14.4 g, 75%) as a yellow oil: 1H NMR (500 MHz, CDCl3) δ 8.19 (d, J=9.2 Hz, 2H), 7.46 (d, J=9.2 Hz, 2H), 3.73 (q, J=7.1 Hz, 1i), 1.49 (d, J=7.1 Hz, 3H), 1.40 (s, 9H).

1. stirringthe reaction stirred for a further 2 h
2. customThe ice bath was then removed
3. waitthe reaction left
4. stirringto stir at room temperature overnight
5. concentrationAfter this time, the solvents were concentrated under reduced pressure
6. dissolutionthe solids redissolved in ethyl acetate (200 mL)
7. washThe organic layer was then washed with saturated sodium bicarbonate (200 mL), 1 M citric acid (200 mL) and brine (200 mL)
8. dry with materialdried over magnesium sulfate
9. filtrationfiltered
10. concentrationconcentrated under reduced pressure
11. customPurification by flash chromatography (silica, 1:20 ethyl acetate/hexanes)