Dichloromethane → HCID 178515546, compound

Participants

Reaction Steps

456 g of bisphenol A and 559 g of 2-[4-hydroxyphenyl]-2-[5-(8-hydroxyquinolyl)]-propane are dissolved in 4 kg of 9% strength sodium hydroxide solution and 9 kg of methylene chloride are then added. 562.8 g of phosgene are introduced with vigorous stirring and 60 ml of a 4% strength triethylamine solution are then added dropwise. The mixture is stirred for a further hour and if necessary sufficient sodium hydroxide solution is added for the pH of the solution to remain constant at 13. The phases are separated and the aqueous phase is tested for complete conversion. The organic phase is extracted once with 5% strength H3PO4, washed with water until neutral and subsequently dried over sodium-sulphate. The organic phase is concentrated and the short-chain polycarbonate with hydroxyquinoline end groups is obtained direct by precipitation in methanol. ηrel : 1.038 (ηrel is measured in CH2Cl2 at 20° C.; 0.5 g solved in 100 g solution); nitrogen analysis: N2 2.56%; phenolic OH: 2.8%. The molecular weight calculated from these values is Mn =1178.

Provenance & Evidence