Article · Wikipedia archive · Last revised Jun 15, 2026

4-Iodophenol

4-Iodophenol (p-iodophenol) is an aromatic organic compound. A colorless solid, it is one of three monoiodophenols. 4-Iodophenol undergoes a variety of coupling reactions in which the iodine substituent is replaced by a new carbon group para to the hydroxy group of the phenol. It is also used to enhance chemiluminescence for detection of cancer cells and in the Eclox assay.

Last revised
Jun 15, 2026
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Source
4-Iodophenol
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Names
IUPAC name
4-Iodophenol
Other names
    • p-Iodophenol
    • para-Iodophenol
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard 100.007.951
EC Number
  • 208-745-5
UNII
  • InChI=1S/C6H5IO/c7-5-1-3-6(8)4-2-5/h1-4,8H
    Key: VSMDINRNYYEDRN-UHFFFAOYSA-N
  • C1=CC(=CC=C1O)I
Properties
C6H5IO
Molar mass 220.009 g·mol−1
Density 1.8573 g/cm3 (112 °C)1
Melting point 93.5 °C (200.3 °F; 366.6 K)1
Boiling point 139 °C (282 °F; 412 K)1 (5 mmHg; decomposes)
Acidity (pKa) 9.332
Hazards
GHS labelling:
GHS07: Exclamation markGHS05: Corrosive3
H302, H312, H314
P280, P305+P351+P338, P310
Related compounds
Related compounds
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

4-Iodophenol (p-iodophenol) is an aromatic organic compound. A colorless solid, it is one of three monoiodophenols. 4-Iodophenol undergoes a variety of coupling reactions in which the iodine substituent is replaced by a new carbon group para to the hydroxy group of the phenol.3 It is also used to enhance chemiluminescence for detection of cancer cells4 and in the Eclox assay.

4-Iodophenol can be prepared from 4-aminophenol via the diazonium salt. An alternative synthesis involves reaction of salicylic acid with iodine, followed by decarboxylation.5

References

References

  1. Haynes, p. 3.324
  2. Haynes, p. 5.93
  3. "4-Iodophenol". Sigma-Aldrich.
  4. "4-Iodophenol". Fisher Scientific.
  5. Dains, F. B.; Eberly, Floyd (1935). "p-Iodophenol". Organic Syntheses. 15: 39. doi:10.15227/orgsyn.015.0039.

Cited sources