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Banerjee et al.
1-Bromomethyl-7-methoxynaphthalene (4)
To a solution of the naphthalene 3 (1.08 g, 6.19 mmol) in carbon tetrachloride (60 mL)
was added N-bromosuccinimide (1.86 g, 10.45 mmol) and benzoyl peroxide (477 mg,
1.97 mmol). The mixture was stirred and heated under reflux in a microwave oven at
280W for 1.5 h. The reaction mixture was cooled to room temperature, filtered to remove
succinimide and washed with carbon tetrachloride. The combined filtrate was evaporated
in vacuo to afford an oil which was chromatographed (hexane:ether 9:1) to afford the
naphthalene 4 (1.51 g, 97%) as a pale yellow solid, Rf 0.62 (hexane), mp. 85–87◦C (from
hexane). MS (m/z): 251 (M+), 171 (M+ −80); 1H NMR: δ 7.82 (d, 1H, ArH-4, J = 8 Hz);
7.80 (d, 1 H, ArH-5, J = 8 Hz), 7.55–7.52 (dd. 1H, ArH-6, J = 7.1 Hz, 1.2 Hz), 7.41 (d, 1H,
ArH-8, J = 2.5 Hz), 7.22–7.18 (dd, 1H, ArH-2, J = 8 Hz, 2.5 Hz), 7.31–7.26 (t, 1H, ArH-3,
J = 7.1 Hz), 4.98 (s, 2H, H at C-11), 3.98 (s, 3H, OMe); 13C NMR: δ 158.4 (ArC-7), 132.7
(ArC-9), 132.3 (ArC-10), 131.9 (ArH-1), 130.6 (ArC-4), 129.7 (ArC-2), 128.6 (ArC-5),
123.3 (ArC-3), 119.1 (ArC-6), 102.9 (ArC-8), 55.7 (ArC-12), 33.1 (ArC-11).
Anal. Calcd. for C12H11BrO: C, 57.37; H, 4.38. Found: C, 57.62; H, 4.54.
7-Methoxy-1-naphthylacetonitrile (5)
To a solution of the compound 4 (501 mg, 1.99 mmol) in dimethyl sulfoxide (15 mL) was
added sodium cyanide (129 mg, 1.84 mmol) and the solution was heated (140–145◦C)
for 3 h. The reaction mixture was cooled, diluted with water and extracted with ether. The
organic extract was washed with brine, dried and evaporated in vacuo. The resulting oil was
chromatographed (hexane:ether 1:1) to afford the nitrile 6 (388 mg, 99%) as pale orange
colored solid, Rf 0.64 (ether), mp. 56–58◦C (from ether). IR (cm−1): 2500 (CN); MS (m/z):
1
197 (M+); H NMR: δ 7.84 (d, 1H, ArH-4, J = 9 Hz), 7.81 (d, 1H, ArH-5, J = 8 Hz),
7.55–7.52 (dd, 1H, ArH-6, J = 7 Hz, 1 Hz), 7.35 (t, 1H, ArH-3, J = 7 Hz), 7.25–7.21 (dd,
1H, ArH-2, J = 9 Hz, J = 2 Hz), 7.11 (d, 1H, ArH-8, J = 2 Hz), 4.10 (s, 2H, ArH-11),
13
3.96 (s, 3H, OMe); C NMR: δ 158.8 (ArC-7), 131.1 (ArC-4), 129.4 (ArC-9), 129.1
(ArC-3), 128.1 (ArC-1), 127.4 (ArC-5), 125.2 (ArC-10), 123.5 (ArC-2), 119.0 (Ar C-6),
118.1 (ArC-13), 101.7 (ArC-8), 55.7 (ArC-12), 22.2 (ArC-11).
Anal. Calcd. for C13H11NO: C, 79.18; H, 5.58. Found: C, 79.41; H, 5.74.
7-Methoxy-1-naphthylacetic acid (2)
A mixture of the nitrile 5 (100 mg, 0.50 mmol) and an aqueous solution of sodium hydroxide
(15 mL, 50%) was heated under reflux in a microwave oven at 60W for 40 min at 120◦C.
The reaction mixture was cooled, diluted with water, neutralized with aqueous HCl (10%)
and extracted with chloroform. The organic extract was washed with brine, dried and
evaporated in vacuo to afford the acid 2 (100 mg, 93%) as white solid (from ether), Rf 0.4
(ether), mp. 148–150◦C (from ether), (lit.3 150–152◦C). IR (cm−1): 3548 (OH), 1700 (CO);
MS (m/z) 216 (M+) and 171 (M+ COOH); 1H NMR: δ 7.78 (d, 1H, ArH-4, J = 8 Hz),
7.6 (d, 1H, ArH-5, J = 8 Hz), 7.39 (d, 1H, ArH-6, J = 8 Hz), 7.31 (t, 1H, ArH-3, J =
8 Hz), 7.23 (d, 1H, ArH-8, J = 2 Hz), 7.18–7.16 (dd, 1H, ArH-2, J = 8 Hz, J = 2 Hz), 4.06
(s, 1H, ArH-11), 3.88 (s, 3H, OMe); 13C NMR: δ 177.8 (ArC-13), 158.5 (ArC-7), 133.6