[C:1]([C:3]1[CH:8]=[CH:7][C:6]([CH2:9][CH2:10][CH2:11][C:12]([O:14][CH2:15][CH3:16])=[O:13])=[CH:5][C:4]=1[O:17]C(C)(C)C)#[N:2].CCOCC.O>C(#N)C.Cl.C(Cl)(Cl)Cl>[C:1]([C:3]1[CH:8]=[CH:7][C:6]([CH2:9][CH2:10][CH2:11][C:12]([O:14][CH2:15][CH3:16])=[O:13])=[CH:5][C:4]=1[OH:17])#[N:2]Ethyl 4-(4-cyano-3-t-butoxyphenyl)butanoate (6.8 g, 23.5 mmol) was dissolved in a mixture of acetonitrile (42 mL) and conc. HCl (3.85 mL) and allowed to stand for 80 min. The reaction was poured into ether/water and the ether layer separated. The ether layer was washed with water and brine, and the combined aqueous washes were reextracted once with ether. The combined ether layers were dried over sodium sulfate and concentrated to give 5.1 g of an off white waxy solid. This material was loaded onto a silica gel column (5×15 cm) in CHCl3 and eluted with 20% EtOAc in CHCl3 to yield 4.5 g of ethyl 4-(4-cyano-3-hydroxyphenyl)butanoate: 1H-NMR (CDCl3) 8.2 (1H, s), 7.42 (1H, d), 6.95 (1H, s), 6.77 (1H, d), 4.2 (2H, q), 2.63 (2H, dd), 2.39 (2H, dd), 1.96 (2H, m), 1.28 (3H, t); 13C (CDCl3) 174.4, 159.5, 149.2, 132.8, 120.8, 117.0, 116.1, 97.1, 60.9, 35.2, 33.6, 25.7. 14.1.
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