1-(2-Pyridylazo)-2-naphthol Property

Melting point:

138-141 °C (lit.)

Boiling point:

392.37°C (rough estimate)

Density 

1.1469 (rough estimate)

refractive index 

1.5700 (estimate)

storage temp. 

Store at +5°C to +30°C.

pka

8.86±0.50(Predicted)

form 

Powder/Solid

color 

green to red, upon chelation with metal

Water Solubility 

Insoluble

BRN 

206390

Stability:

Stable. Incompatible with strong oxidizing agents, strong bases.

CAS DataBase Reference

85-85-8(CAS DataBase Reference)

NIST Chemistry Reference

2-Naphthalenol, 1-(2-pyridinylazo)-(85-85-8)

EPA Substance Registry System

2-Naphthalenol, 1-(2-pyridinylazo)- (85-85-8)

Safety

Hazard Codes 

Xi

Risk Statements 

36/37/38

Safety Statements 

26-36-37/39

WGK Germany 

3

TSCA 

Yes

HS Code 

29333999

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H315Causes skin irritation

H319Causes serious eye irritation

H335May cause respiratory irritation

Precautionary statements

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P304+P340IF INHALED: Remove victim to fresh air and Keep at rest in a position comfortable for breathing.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P405Store locked up.

1-(2-Pyridylazo)-2-naphthol Chemical Properties,Usage,Production

Uses

1-(2-Pyridylazo)-2-naphthol is an indicator of transition metals. 1-(2-Pyridylazo)-2-naphthol is an indicator in complexometry and a reagent for the extraction and spectrophotometric determination of many transition metals. Dyes and metabolites.

Chemical Properties

orange crystals

Uses

1-(2-Pyridylazo)-2-naphthol is an indicator of transition metals. 1-(2-Pyridylazo)-2-naphthol is an indicator in complexometry and a reagent for the extraction and spectrophotometric determination of many transition metals. Dyes and metabolites.

Definition

ChEBI: 1-(2-pyridin-2-yldiazenyl)-2-naphthol is a member of naphthols.

General Description

1-(2-Pyridylazo)-2-naphthol (PAN), an orange colored dye, is commonly used as an acid-base indicator. It can form chelates with metal ions, which makes it a valuable indicator in complexometric titrations. PAN is also a spectrophotometric reagent, which can extract metal chelates into an organic solvent.

Agricultural Uses

1-(2-Pyridylazo)-2-naphthol is a hard stratum of strongly compacted soil caused by continual plowing to the same depth of hardened soil which has high clay content. The precipitated iron and silicates cement the soil particles and form pans. 1-(2-Pyridylazo)-2-naphthol often impede drainage and root growth. It can be broken up using a subsoiler .

Purification Methods

Purify PAN by repeated crystallisation from EtOH or MeOH. It can also be purified by sublimation under vacuum. Purity can be checked by TLC using a mixed solvent (pet ether/Et2O/EtOH; 10:10:1) on a silica gel plate. It has pK1 1.9 and pK2 12.2 in 20% aqueous ethoxyethanol. It chelates with copper [Pease & Williams Anal Chem 31 1046 1959]. [Beilstein 22 I 694, 22 III/IV 7073, 22/4 V 618.]