1-Bromo-4-iodobenzene explained

1-Bromo-4-iodobenzene is a mixed aryl halide (aryl bromide and aryl iodide) with the formula BrC₆H₄I.^[1]

Preparation

In one laboratory route to 1-bromo-4-iodobenzene, 4-bromoaniline is treated with concentrated sulfuric acid and sodium nitrite to form the diazonium salt, which is then treated with potassium iodide to form 1-bromo-4-iodobenzene.^[2]

Reactions

Since aryl iodides are more reactive than aryl bromides in the Sonogashira coupling, the iodine end of 1-bromo-4-iodobenzene can be selectively coupled to a terminal acetylene while leaving the bromine end unreacted, by running the reaction at room temperature. For example, two equivalents of 1-bromo-4-iodobenzene can couple to trimethylsilylacetylene in a room temperature symmetrical Sonogashira coupling (with TMSA being deprotected to acetylene in-situ) to form bis(4-bromophenyl)acetylene.^[3]

See also

• Bromobenzene
• Iodobenzene
• Bromochlorobenzene

Notes and References

1. Web site: PubChem . 1-Bromo-4-iodobenzene . 2023-10-22 . pubchem.ncbi.nlm.nih.gov . en.
2. Banerjee . M. . Shukla . R. . Rathore . R. . 15 January 2009 . Synthesis, Optical, and Electronic Properties of Soluble Poly-p-phenylene Oligomers as Models for Molecular Wires . . 131 . 5 . 1780–1786 . 10.1021/ja805102d. 19146375 .
3. Mio . Matthew J. . Kopel . Lucas C. . Braun . Julia B. . Gadzikwa . Tendai L. . Hull . Kami L. . Brisbois . Ronald G. . Markworth . Christopher J. . Grieco . Paul A. . 2002 . One-Pot Synthesis of Symmetrical and Unsymmetrical Bisarylethynes by a Modification of the Sonogashira Coupling Reaction . . 4 . 19 . 3199–3202 . 10.1021/ol026266n. 12227748 .