Bitertanol

Bitertanol
Names
IUPAC name
3,3-dimethyl-1-(4-phenylphenoxy)-1-(1,2,4-triazol-1-yl)butan-2-ol
Other names
  • Baycor
  • Biloxazol
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.054.084 Edit this at Wikidata
EC Number
  • 259-513-5
KEGG
  • InChI=1S/C20H23N3O2/c1-20(2,3)18(24)19(23-14-21-13-22-23)25-17-11-9-16(10-12-17)15-7-5-4-6-8-15/h4-14,18-19,24H,1-3H3
    Key: VGPIBGGRCVEHQZ-UHFFFAOYSA-N
  • CC(C)(C)C(C(N1C=NC=N1)OC2=CC=C(C=C2)C3=CC=CC=C3)O
Properties
C20H23N3O2
Molar mass 337.423 g·mol−1
Appearance colorless
Density 1.16 g·cm−3
log P 4.1
Vapor pressure 0.0000075 mmHg
Hazards
GHS labelling:
GHS06: ToxicGHS07: Exclamation mark
Danger
H302, H330
P260, P264, P270, P271, P284, P301+P317, P304+P340, P316, P320, P330, P403+P233, P405, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Bitertanol is a mixture of four isomers, which are chemical compounds belonging to the triazole and biphenyl derivative classes.

Properties

Bitertanol is a colorless, water-insoluble solid. The commercial product is a 20:80 mixture of the (1RS,2RS)- and (1RS,2SR)-isomers.

It is highly stable toward photolysis and hydrolysis. Its half-life in aqueous suspension is 39.2 days.

Synthesis

Bitertanol can be prepared via a multi-step reaction starting from 3,3-dimethyl-2-butanone: chlorination with elemental chlorine is followed by nucleophilic substitution of the chlorine atom with 4-phenylphenol, bromination with elemental bromine, subsequent nucleophilic substitution with 1,2,4-triazole, and final reduction of the ketone with hydrogen.

Synthesis of Bitertanol
Synthesis of Bitertanol

Uses

Bitertanol is used as a fungicide for the preventive or curative treatment of diseases in fruit and vegetable crops, including Venturia species and Monilia laxa in stone fruit, as well as a seed treatment against Fusarium, Septoria, wheat scab, and other pathogens. It was introduced to the market in 1979 by Bayer AG.

Approval

The European Union approved its use as an active substance in plant protection products, effective January 1, 2012, specifically as a fungicide for seed treatment. This approval expired in August 2013.

In European countries such as Germany and Austria, as well as Switzerland, no plant protection products containing this active substance are approved.

References

  1. 1 2 3 4 "Bitertanol". pubchem.ncbi.nlm.nih.gov. Retrieved 2026-10-16.
  2. 1 2 F. Müller, P. Ackermann, P. Margot: Fungicides, Agricultural, 2. Individual Fungicides. In: Ullmanns Enzyklopädie der Technischen Chemie. Wiley-VCH, Weinheim 2012, doi:10.1002/14356007.o12_o06.
  3. ↑ Sigma-Aldrich Co., Bitertanol, PESTANAL. Retrieved on 2017-05-19.
  4. ↑ EFSA: Conclusion on the peer review of the pesticide risk assessment of the active substance bitertanol, 2010. doi:10.2903/j.efsa.2010.1850
  5. ↑ Terence Robert Roberts, David Herd Hutson (1999), Metabolic Pathways of Agrochemicals: Part 2, Insecticides and fungicides, Royal Society of Chemistry, p. 1018, ISBN 0-85404-499-X
  6. ↑ Thomas A. Unger (1996), Pesticide Synthesis Handbook, William Andrew, p. 685, ISBN 0-08-095716-1
  7. ↑ FAO: Bitertanol (PDF; 548 kB).
  8. ↑ Ulrich Schirmer, Peter Jeschke, Matthias Witschel (2012), Modern Crop Protection Compounds: Herbicides, John Wiley & Sons, p. 771, ISBN 978-3-527-32965-6{{citation}}: CS1 maint: multiple names: authors list (link)
  9. ↑ Durchführungsverordnung (EU) Nr. 1278/2011 der Kommission vom 8. Dezember 2011 zur Genehmigung des Wirkstoffs Bitertanol gemäß der Verordnung (EG) Nr. 1107/2009... (PDF).
  10. ↑ Generaldirektion Gesundheit und Lebensmittelsicherheit der Europäischen Kommission: Eintrag zu Bitertanol in der EU-Pestiziddatenbank; Eintrag in den nationalen Pflanzenschutzmittelverzeichnissen der Schweiz, Österreichs und Deutschlands, abgerufen am 13. August 2025.