[H-].[Na+].[C:3]([CH2:5][C:6]([O:8][CH2:9][CH3:10])=[O:7])#[N:4].[H][H].C1(C)C=C(C)C=C(C)C=1[CH2:21][CH2:22][CH2:23][CH2:24][C:25]1[CH:34]=[CH:33][C:28]([C:29]([O:31][CH3:32])=[O:30])=[CH:27][CH:26]=1>O1CCCC1>[C:6]([CH:5]([C:3]#[N:4])[CH2:21][CH2:22][CH2:23][CH2:24][C:25]1[CH:26]=[CH:27][C:28]([C:29]([O:31][CH3:32])=[O:30])=[CH:33][CH:34]=1)([O:8][CH2:9][CH3:10])=[O:7]A mixture of 10.30 g (1.1 eq) of 80% sodium hydride in mineral oil is washed twice with anhydrous tetrahydrofuran (to remove the mineral oil) and 400 mL of tetrahydrofuran are then added. This is cooled to 0° C. and a solution of 35.29 g (1.0 eq) of ethyl cyanoacetate in anhydrous tetrahydrofuran is added dropwise under nitrogen. The mixture is stirred vigorously at ambient temperatures until the evolution of hydrogen ceases and an anhydrous solution of 89.33 g (1.0 eq) of methyl 4-(4-mesitylbutyl)benzoate is then added in a dropwise fashion. The mixture is stirred at ambient temperatures for 12 hours, then at reflux temperatures for 6 hours, and then cooled. The solvent is removed under reduced pressure and diethyl ether is added. The organic phase is separated, washed with water and brine, dried over magnesium sulfate, filtered and concentrated. The residue is chromatographed with 1:4 ethyl acetate:hexane and the homogeneous fractions are combined and concentrated to yield methyl 4-(5-carboethoxy-5-cyanopentyl)benzoate as a liquid, IR (film) vmax 2915, 2860, 2255, 1730, 1609, 1571, 1432, 1413, 1368, 1320, 1178, 1105, 1019, 962, 853, 759, and 602 cm-1 ; 1H NMR (CDCl3) delta 7.95 (d, J=8.1 Hz, 2H, Ar), 7.24 (d, J=8.1 Hz, 2H, Ar), 4.25 (q, J=7.2 Hz, 2H, CH2CH3), 3.90 (s, 3H, CO2CH3), 3.46 (t, J=6.8 Hz, 1H, CHCN), 2.69 (t, J=7.5 Hz, 2H, benzyl), 1.93-2.00 (m, 2H, CH2CH), 1.54-1.72 (m, 4H, 2° aliphatic), 1.30 (t, J=7.3 Hz, 3H, CH2CH3).
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