4-Bromophenylacetic acid explained

4-Bromophenylacetic acid, also known as p-bromophenylacetic acid, is an organic compound. It is a derivative of phenylacetic acid containing a bromine atom in the para position.

Preparation

4-Bromophenylacetic acid may be prepared by the addition of a bromine atom to phenylacetic acid through electrophilic aromatic substitution. It was first prepared in the laboratory by treatment of phenylacetic acid with bromine and mercuric oxide; a mixture of the 2- and 4- isomers is made, and the 4- isomer is isolated by fractional crystallization.^[1]

It can also be made by condensing 4-bromobenzyl bromide with sodium cyanide in ethanol, and then hydrolyzing the nitrile with sodium hydroxide.

Reactions

Methyl 4-bromophenylacetate is made from 4-bromophenylacetic acid by Fischer esterification, refluxing it with methanol acidified with sulfuric acid.^[2] An ethyl ester can be made in an analogous way using ethanol instead of methanol.

A hydrazone derivative, 2-(4-bromophenyl)acetohydrazide, is made by refluxing the methyl ester with hydrazine.^[2] Further hydrazone derivatives of 4-bromophenylacetic acid are made by condensing the simple hydrazone with aldehydes, forming a double bond with the second nitrogen.^[2] At least 19 of these hydrazones are known.^[2]

4-Bromophenylacetic acid is a chemical that can be purchased.^[3]

Plant protoplasts conjugate aspartic acid with 4-bromophenylacetic acid to form 4-bromophenylacetyl-L-aspartic acid.^[4]

4-Bromophenylacetic acid reacts with sodium tetraphenylborate to form felbinac which can be further converted to xenbucin.^[5]

Properties

The ionic conductance has been measured.^[6]

Notes and References

1. Bedson . P. Philips . 1880 . VIII.—On some derivatives of phenylacetic acid . Journal of the Chemical Society, Transactions . 37 . 90–101 . 10.1039/CT8803700090.
2. Khan . Imtiaz . Ibrar . Aliya . Ejaz . Syeda Abida . Khan . Shafi Ullah . Shah . Syed Jawad Ali . Hameed . Shahid . Simpson . Jim . Lecka . Joanna . Sévigny . Jean . Iqbal . Jamshed . Influence of the diversified structural variations at the imine functionality of 4-bromophenylacetic acid derived hydrazones on alkaline phosphatase inhibition: synthesis and molecular modelling studies . RSC Advances . 2015 . 5 . 110 . 90806–90818 . 10.1039/C5RA14836G. 2015RSCAd...590806K .
3. Field . Jennifer A. . Reed . Ralph L. . Nonylphenol Polyethoxy Carboxylate Metabolites of Nonionic Surfactants in U.S. Paper Mill Effluents, Municipal Sewage Treatment Plant Effluents, and River Waters . Environmental Science & Technology . 1 November 1996 . 30 . 12 . 3544–3550 . 10.1021/es960191z. 1996EnST...30.3544F .
4. Aranda . Gérard . Muller . Jean-François . Caboche . Michel . Conjugation of aspartic acid with 4-bromophenylacetic acid, an auxin analogue of aspartic acid . Phytochemistry . January 1987 . 26 . 8 . 2145–2147 . 10.1016/S0031-9422(00)84675-0.
5. Kuuloja . Noora . Kylmälä . Tuula . Xu . Youjun . Franzén . Robert . Synthesis of Xenbucin using Suzuki reaction catalyzed by Pd/C in water . Open Chemistry . 1 September 2008 . 6 . 3 . 390–392 . 10.2478/s11532-008-0044-1. 94911885 . free .
6. Book: Holze . Rudolf . Ionic conductance of p-bromophenylacetic acid . Electrochemistry . 2016 . 573 . 10.1007/978-3-662-49251-2_540. 978-3-662-49249-9 .