Phenidone

Phenidone
Names
Preferred IUPAC name
1-Phenylpyrazolidin-3-one
Identifiers
3D model (JSmol)
ChEMBL
ChemSpider
ECHA InfoCard 100.001.960 Edit this at Wikidata
EC Number
  • 202-155-1
UNII
  • InChI=1S/C9H10N2O/c12-9-6-7-11(10-9)8-4-2-1-3-5-8/h1-5H,6-7H2,(H,10,12) checkY
    Key: CMCWWLVWPDLCRM-UHFFFAOYSA-N checkY
  • InChI=1/C9H10N2O/c12-9-6-7-11(10-9)8-4-2-1-3-5-8/h1-5H,6-7H2,(H,10,12)
    Key: CMCWWLVWPDLCRM-UHFFFAOYAF
  • O=C2NN(c1ccccc1)CC2
Properties
C9H10N2O
Molar mass 162.192 g·mol−1
Appearance Crystal leaflets or needles
Melting point 121 °C (250 °F; 394 K)
10 g/100 ml at 100 °C
Solubility in ethanol 10 g/100 ml (hot)
Solubility in diethyl ether practically insoluble
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
 Harmful if swallowed
GHS labelling:
GHS07: Exclamation markGHS09: Environmental hazard
Warning
H302, H411
P264, P270, P273, P301+P312, P330, P391, P501
Safety data sheet (SDS) External MSDS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

Phenidone (1-phenyl-3-pyrazolidinone) is an organic compound that is primarily used as a photographic developer. It has five to ten times the developing power as Metol. It also has low toxicity and unlike some other developers, does not cause dermatitis upon skin contact.[1]

Phenidone is Ilford's trademark for this material, which was first prepared in 1890. It was not until 1940 that J. D. Kendall, in the laboratories of Ilford Limited, discovered the reducing properties of this compound. Large scale production did not become feasible until 1951.[2]

Phenidone functions as a reducing agent. It converts to the N-phenyl-hydroxypyrazole:

Reaction of phenidone with silver bromide, as occurs in photographic development
  1. ^ Merck Index of Chemicals and Drugs, 9th ed. monograph 7115
  2. ^ Karlheinz Keller et al. "Photography" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim. doi:10.1002/14356007.a20_001