Preparation of bromine-containing aromatic compounds and their application as flame retardants

Patent metadata

Field	Value
Publication number	US-9988332-B2
Application number	US-201615284596-A
Country	US
Kind code	B2
Filing date	Oct 4, 2016
Priority date	Jan 6, 2013
Publication date	Jun 5, 2018
Grant date	Jun 5, 2018

Abstract

The invention relates to compounds of the formula Ar(—CH 2 C 6 Br 5 ) y , wherein Ar indicates a structure comprising one or more six-membered aromatic ring(s) and —CH 2 C 6 Br 5 indicates a pentabromobenzyl group, characterized in that at least one carbon atom of said six-membered aromatic ring(s) is bonded to the benzylic carbon of said —CH 2 C 6 Br 5 group, wherein y, which indicates the number of the —CH 2 C 6 Br 5 groups in said compound, is not less than 1. Processes for preparing the compounds and their use as flame retardants are also disclosed.

First claim

The invention claimed is:

1. A process for preparing a compound of the formula Ar(—CH 2 C 6 Br 5 ) y , wherein Ar indicates a structure comprising one or more six-membered aromatic ring(s), —CH 2 C 6 Br 5 is the pentabromobenzyl group and y indicates the number of the —CH 2 C 6 Br 5 groups in the compound, said process comprises a Friedel-Crafts alkylation reaction of pentabromobenzyl halide with a reactant, wherein said reactant contains one or more six-membered aromatic rings, in the presence of a Friedel-Crafts catalyst, to form said Ar(CH 2 C 6 Br 5 ) y compound having not less than two —CH 2 C 6 Br 5 groups bonded to each said one or more six-membered aromatic rings, such that the bond is between a carbon atom of the six-membered aromatic ring and the benzylic carbon of the pentabromobenzyl group.

2. A process according to claim 1 , wherein three —CH 2 C 6 Br 5 groups are attached to each six-membered aromatic rings present in the reactant.

3. A process according to claim 1 , wherein the Friedel-Crafts catalyst is selected from the group consisting of AlCl 3 , AlBr 3 , GaCl 3 , FeCl 3 , SnCl 4 , SbCl 3 , ZnCl 2 , CuCl 2 and HF.

4. A process according to claim 1 , wherein the reactant is a compound of Formula (II):

wherein R is H or a linear or branched aliphatic chain, m is 0 or 1, k is an integer from 1 to 3, X=null, an alkylene group containing 1 to 10 carbon atoms, O and S.

5. A process according to claim 4 , wherein the reactant is selected from the group consisting of:
Toluene, wherein in Formula II m=0, R=CH 3 , k=1;
Xylene, wherein in Formula II m=0, R=CH 3 , k=2;
Ethylbenzene, wherein in Formula II m=0, R=C 2 H 5 , k=1;
Diphenyl ether, wherein in Formula II m=1, R=H, X=O;
Diphenylmethane, wherein in Formula II m=1, R=H, X=—CH 2 —; and
Diphenylethane, wherein in Formula II m=1, R=H, X=—(CH 2 ) 2 —.

6. A process according to claim 5 , comprising a Friedel-Crafts alkylation reaction of pentabromobenzyl bromide with a reactant selected from the group consisting of toluene, xylene, ethylbenzene, diphenyl ether, diphenylmethane and diphenylethane in the presence of aluminum chloride, wherein the molar ratio between said pentabromobenzyl bromide and said reactant is at least equal to twice the number of the six-membered aromatic rings of said reactant.

7. A process according to claim 1 , wherein the Friedel-Crafts alkylation reaction takes place in a solvent which is halogenated aliphatic hydrocarbon.

8. A product mixture consisting of homologous series of the formula Ar(—CH 2 C 6 Br 5 ) y , where Ar indicates a structure comprising one or more six-membered aromatic ring(s) and —CH 2 C 6 Br 5 indicates a pentabromobenzyl group, wherein the benzylic carbon of said —CH 2 C 6 Br 5 group is bonded to a carbon atom of said six-membered aromatic ring(s), and further wherein said homologous series comprises the compound Ar(—CH 2 C 6 Br 5 ) 3m+3 , where m+1 is the number of the six-membered aromatic rings in Ar.

Assignees

• Bromine Compounds Ltd

Inventors

• Gelmont Mark
• Yuzefovitch Michael
• Yoffe David
• Frim Ron

Classifications

• C07C41/14 Primary

  by exchange of organic parts on the ether-oxygen for other organic parts, e.g. by trans-etherification · CPC title

• C09K21/08 Primary

  containing halogen · CPC title

• C07C43/29

  containing halogen · CPC title

• C08K5/06

  Ethers; Acetals; Ketals; Ortho-esters · CPC title

• C07C17/275

  of hydrocarbons and halogenated hydrocarbons · CPC title