Nitrogen → 4,4'-Tolan-dicarboxylic acid di-tert.-butyl ester

Participants

Reaction Steps

4-Bromo-benzoic acid tert.-butyl ester, 5.1 g of triphenylphosphine and 375 ml of NEt3 are introduced into 1 l of absolute acetonitrile under nitrogen and N2 is passed through the solution for 20 minutes. 10.5 g of (Pφ3)2PdCl2 and 1.5 g of copper(I)iodide are then added and 166.5 g of 4-ethinyl-benzoic acid tert.-butyl ester dissolved in 1 l of absolute acetonitrile are slowly added dropwise under reflux and the reaction mixture is stirred overnight. The resulting reaction mixture is then suction filtered after cooling, stirred up in water, again suction filtered, dissolved in CH2Cl2 and filtered after the addition of a small quantity of Tonsil, and the solvent is then evaporated off under vacuum. 225 g of 4,4'-Tolan-dicarboxylic acid-di-tert.-butyl ester are obtained.

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