2,2-Bis[4-(2,3-dibromopropoxy)-3,5-dibromophenyl]-propane process
AssigneeRiedel-de Haen Aktiengesellschaft
InventorsWolfgang Dannenberg, Walter Heyer, Theo Doldissen, Manfred Zimmermann
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Abstract
2,2-Bis[4-(2,3-dibromopropoxy)-3,5-dibromophenyl]-propane (BDDP) has the structural formula ##STR1## This bisphenol-A derivative is prepared by reaction of 2,2-bis[4-hydroxy-3,5-dibromophenyl]-propane with an allyl halide and subsequent bromination of the diallyl ether obtained. In the first reaction step, a lower aliphatic alcohol is used as solvent, and in the second reaction step an aromatic halogenated hydrocarbon. The reaction product is then precipitated by excess alcohol, and separated. The BDDP is obtained in the form of granules and is suitable for application as flameproofing agent.
Claims12
A process for the manufacture of 2,2-bis[4-(2,3-dibromopropoxy)-3,5-dibromophenyl]-propane by reaction of 2,2-bis[4-hydroxy-3,5-dibromophenyl]-propane with an allyl halide in an alcoholic solution and bromination of the allyl ether obtained with bromine, which comprises (a) reacting 2,2-bis[4-hydroxy-3,5-dibromophenyl]-propane with the allyl halide in solution in a mixture of water and a lower aliphatic alcohol, (b) removing the lower aliphatic alcohol, (c) dissolving the allyl ether obtained according to (b) in an aromatic halogenated hydrocarbon and removing the water, without further workup of the allyl ether after it is dissolved in the aromatic halogenated hydrocarbon in step (c), (d) brominating the allyl ether with bromine (e) removing the excess bromine, (f) washing the thus obtained brominated allyl ether solution obtained according to (e) with water, (g) precipitating the brominated allyl ether by means of a lower aliphatic alcohol, and subsequently separating it.
Dependencies are inferred from the claim text.