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A mixture of 230 g (1.0 mole) of methyl-α-bromo-m-toluate and 300 g (1.2 mole) of triphenyl phosphine in 1 l of dry benzene was refluxed for 2 hr. After 15 minutes, the phosphonium bromide started precipitating from the solution. After cooling the flask to room temperature, the solid was filtered, washed with plenty of petroleum ether and dried. The yield 487 g was quantitative. m.p. 234°-236° C. The infrared spectrum showed absorption of 1720 cm-1 (COOCH3). NMR (CDCl3) showed 3.8 (S, --COOCH3, 3), 5.5-5.8 (d, --CH2 -P, 2), and 7-8.4 (m, aromatic, 19). Anal. calcd. for C27H24O2P Br: C, 65.98%, H, 4.88%, Br. 16.29%. Found: C, 65.88%, H, 4.82%, Br, 16.49%.

1. temperaturewas refluxed for 2 hr
2. customthe phosphonium bromide started precipitating from the solution
3. filtrationthe solid was filtered
4. washwashed with plenty of petroleum ether
5. customdried
6. customabsorption of 1720 cm-1 (COOCH3)