反应详情

A mixture of 514 g of 4-bromobenzoic acid tert.-butyl ester, 88.25 g of 2-methyl-3-butyn-2-ol and 74.5 g of triphenylphosphine in 1250 ml of toluene is added to 7.1 g of benzyl triethylammonium chloride, 9.55 g of copper(I)iodide and 14 g of (Pφ3)2PdCl2 and the reaction mixture is stirred at reflux for 48 hours after the addition of 750 ml of 5.5 N NaOH. The organic phase is separated off, dried and concentrated by evaporation. 430 g of moist crude product are stirred up in 550 ml of methanol and suction filtered. 248 g of 4,4'-tolan-dicarboxylic acid di-tert.-butyl ester are obtained and may be further purified by recrystallisation from acetonitrile.

1. temperatureat reflux for 48 hours
2. customThe organic phase is separated off
3. customdried
4. concentrationconcentrated by evaporation
5. stirring430 g of moist crude product are stirred up in 550 ml of methanol
6. filtrationsuction filtered