4-Bromoanisole

Chemical properties

4-Bromoanisole is a colourless to pale yellow oily liquid with a pleasant smell similar to that of anise seed. Insoluble in water, soluble in ethanol, ether and chloroform. It is one of three isomers of bromoanisole, the others being 3-bromoanisole and 2-bromoanisole. It is the precursor to many 4-anisyl derivatives.

The Uses of 4-Bromoanisole

4-Bromoanisole finds application as an intermediate in synthetic chemistry. It is used in the preparation of aryl 1,3-diketones and ethyl 4-methoxycinnamate. It is a used as a brominating reagent. Further, it is used in Suzuki coupling reaction with phenylboronic acid as well as in Heck reaction.

Definition

ChEBI: 4-bromoanisole is a monomethoxybenzene carrying a bromo substituent at position 4. It is a monomethoxybenzene and an organobromine compound.

Preparation

4-Bromoanisole is obtained by reacting p-bromophenol with dimethyl sulfate.

Biological Functions

4-Bromoanisole is compound sometimes used in RNA extraction which serves to further eliminate DNA contamination. It interacts with genomic DNA(gDNA) and through a separation phase, it will be located in the organic layer instead of the aqueous layer (upper layer) containing the RNA extract.

Synthesis Reference(s)

Tetrahedron Letters, 35, p. 7429, 1994 DOI: 10.1016/0040-4039(94)85333-9
Synthesis, p. 868, 1986 DOI: 10.1055/s-1986-31813

General Description

4-Bromoanisole is a useful brominating reagent. It is formed as reaction product in the reaction between HOBr and anisole. Suzuki coupling of 4-bromoanisole with phenylboronic acid catalyzed by palladium pincer complexes has been studied. Heck Reaction of 4-bromoanisole with ethyl acrylates in room-temperature ionic liquids is reported to afford ethyl 4-methoxycinnamate.

Safety Profile

Moderately toxic by ingestion andintraperitoneal routes. When heated to decomposition itemits toxic vapors of Br^-.

Purification Methods

Crystallise the anisole by repeated partial freezing, then distil it under reduced pressure. [Beilstein 6 III 741, 6 IV 1044.]