Synthesis
GENERAL METHOD: Phenol (0.28 mmol) was dissolved in trifluoromethanesulfonic acid (TfOH, 3 mL) with n-pentanoyl chloride (0.28 mmol) at 0 °C. The reaction mixture was gradually warmed up to room temperature according to the conditions shown in Table 2 and kept for an appropriate time. After completion of the reaction, the mixture was poured into a mixture of ice water and ethyl acetate. The organic layer was separated and washed sequentially with 1 M hydrochloric acid, saturated sodium bicarbonate solution and saturated sodium chloride solution. The organic layer was dried over anhydrous magnesium sulfate and filtered, and the filtrate was concentrated. The crude product was purified by silica gel column chromatography to give 4-hydroxyvalerophenone. The spectral data of all the products were in agreement with those reported in the literature.
References
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[2] Chemische Berichte, 1985, vol. 118, # 8, p. 3332 - 3349
[3] Tetrahedron, 1981, vol. 37, # 16, p. 2815 - 2821
[4] Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy, 1998, vol. 54, # 2, p. 285 - 297
[5] Bioorganic and Medicinal Chemistry Letters, 2001, vol. 11, # 6, p. 841 - 844
