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PATIL AND WADIA
7c: Yield 58%, m.p. 46–47ꢁ (Lit.[8,17c] m.p. 46–48ꢁ). IR (nujol): 1740,
1
1680 cmÀ1. H NMR: 4.00 and 4.10 each (3H, s, ArOCH3, COOCH3), 7.20
(2H, d, J ¼ 9.0 Hz, ArH), 8.30 (2H, d, J ¼ 9.0 Hz, ArH).
7d: Yield 66%, b.p. 239ꢁ. IR (neat): 1760, 1700 cmÀ1. H NMR: 0.91
1
(6H, d, J ¼ 9.0 Hz, ÀCH(CH3)2), 2.0 (1H, m, CH2–CH(CH3)2), 2.62 (2H, d,
J ¼ 10.0 Hz, CH2–CH(CH3)2), 4.10 (3H, s, OCH3), 7.54 (2H, d, J ¼ 9.0 Hz,
ArH), 8.20 (2H, d, J ¼ 9.0 Hz, ArH). Analysis: C13H16O3, required: C, 70.91;
H, 7.27%. Found: C, 70.72; H, 7.22%.
7e: Yield 56%, b.p. 304ꢁ (Lit.[13,17d] b.p. 112ꢁ/0.6 mm). IR (neat): 1740,
1680 cmÀ1
.
1H NMR: 1.43 (3H, t, J ¼ 7.5 Hz, OCH2CH3), 2.48 (3H, s,
ArCH3), 4.60 (2H, q, J ¼ 7.5 Hz, ÀOCH2CH3), 7.60 (2H, d, J ¼ 9.0 Hz,
ArH), 8.23 (2H, d, J ¼ 9.0 Hz, ArH).
General Procedure for the Dichloromethylenation of
Ketones or Ketoesters[7]
Triphenyl phosphine (30 mmole) was dissolved in dry dichloro-
methane (20 mL) and tetrachloromethane (22 mmole) was added to the sol-
ution of ketones (10 mmole) or ketoester (10 mmole) at room temperature.
The resultingmixture was refluxed for 48 h. After solvent removal, SiO 2 (3 g)
was added to the residue and this was loaded on a SiO2 (30 g) column. The
ester was obtained in the hexane-EtOAc (98 : 2) fraction.
4: Yield 70%, b.p. 212–214ꢁ (Lit.[6] 92–95ꢁ/13 mm). H NMR: 2.10
1
(3H, s, H3C–C¼CCl2), 7.25 (5H, s, ArH).
2a: Yield 90%, thick liq. (Lit.[6] oil). IR (neat): 1620, 1470, 930 cmÀ1
.
1H NMR: 0.91 (6H, d, J ¼ 6.5 Hz, CH(CH3)2), 1.88 (1H, m, CH2CH(CH3)2),
2.20 (3H, s, CH3C¼CCl2), 2.48 (2H, d, J ¼ 6.5 Hz, ArCH2), 7.19 (2H, d,
J ¼ 9.0 Hz, ArH), 7.27 (2H, d , J ¼ 9.0 Hz, ArH).
6: Yield 65%, m.p. 72–74ꢁ. IR (nujol): 1640, 1610, 1510, 1490,
1
870 cmÀ1. H NMR: 2.25 (3H, s, CH3C¼CCl2), 3.80 (3H, s, ÀOCH3), 7.18
(3H, m, ArH), 7.80 (3H, m, ArH). Mass m/z: 270 (11%), 268 (57%), 266
(95%), 225 (17%), 223 (29%), 220 (28%), 218 (96%), 183 (100%). Analysis:
C14H12Cl2O, required: C, 62.92; H, 4.49%. Found: C , 62.77; H, 4.43%.
8a: Yield 62%, b.p. 262ꢁ. IR: (neat): 1740, 1610, 1600, 1500, 720,
1
700 cmÀ1. H NMR: 3.91 (3H, s, ÀOCH3), 7.65 (5H, bs, ArH). Analysis:
C10H8Cl2O2, required: C, 51.95; H, 3.46%. Found: C, 52.05; H, 3.57%.
8b: Yield 65%, yellowish oil. IR (neat): 1740, 1605, 1430, 790 cmÀ1
.
1H NMR: 2.33 (3H, s, ArCH3), 3.70 (3H, s, COOCH3), 7.13 (4H, bs, ArH).
Analysis: C11H10Cl2O2, required: C, 53.87; H, 4.08%. Found: C, 53.98;
H, 4.18%.