2-Naphthalenesulfonic acid, 6-hydroxy-5-[(4-sulfophenyl)azo]-, disodium salt (CAS 2783-94-0) — Citrus N/A Note Fragrance Ingredient

ByThe Good Scents
Citrus · Floral

2-Naphthalenesulfonic acid, 6-hydroxy-5-[(4-sulfophenyl)azo]-, disodium salt

CAS 2783-94-0

Origin
synthetic
Note
N/A
IFRA
Professional use
Data as of: Apr 2026

What Is 2-Naphthalenesulfonic acid, 6-hydroxy-5-[(4-sulfophenyl)azo]-, disodium salt?

2-Naphthalenesulfonic acid is a synthetic dye compound primarily used in industrial applications. Consumers may encounter it in certain textile dyes or specialized inks. This ingredient does not have significant fragrance applications, as it lacks notable olfactory properties and is valued for its colorant characteristics rather than scent.

Safety Profile

PROFESSIONAL USE
Generally safeUse with awarenessProfessional use
⚠ Industrial chemical – not for fragrance use
✗ No known safe cosmetic applications
CAS
2783-94-0
Formula
Mixture
MW
Variable
Odor Family
Citrus · Floral
Layer 1 · Enthusiast

What Does 2-Naphthalenesulfonic acid, 6-hydroxy-5-[(4-sulfophenyl)azo]-, disodium salt Smell Like?

This compound has no significant odor profile suitable for perfumery applications. As an industrial dye chemical, it was not developed for olfactory characteristics and does not contribute to fragrance compositions. The molecular structure suggests it would likely be odorless or have only faint chemical notes at high concentrations.

Layer 2

2D Molecular Structure

FD&C Yellow 6

SMILES: [Na+].[Na+].OC1=C(N=NC2=CC=C(C=C2)S([O-])(=O)=O)C2=C(C=C1)C=C(C=C2)S([O-])(=O)=O

Chemistry, Properties & Perfumer Guide

The Chemistry

2-Naphthalenesulfonic acid is a synthetic azo dye compound with multiple sulfonate groups that make it water-soluble. The structure contains a naphthalene core with hydroxyl and azo functional groups. Industrial synthesis typically involves diazotization and coupling reactions. The disodium salt form improves solubility for dye applications. This compound belongs to the class of sulfonated azo dyes, which are valued for their colorfast properties rather than fragrance characteristics.

Physical & Chemical Properties

AppearanceSolid powder
Primary UseIndustrial dye

Perfumer Guide

Note Position
N/A
Volatility
N/A
Blending
N/A
ApplicationTypical %RangeNotes
Industrial Dyes0.1-5%Varies by applicationNot for fragrance use

Classic Accords

Tip: This compound is not suitable for perfumery applications.

Alternatives & Comparisons

Layer 3

Safety, Regulatory & Sustainability

⚠ Regulatory Disclaimer

General reference only. Consult current IFRA Standards Library before formulating.

IFRA Status

Not evaluated by IFRA – industrial chemical outside fragrance scope

RIFM Assessment

Not assessed by RIFM – industrial chemical without fragrance applications

Sustainability

As an industrial dye chemical, sustainability considerations focus on manufacturing waste streams and potential water contamination. Synthetic production avoids natural resource depletion but requires careful handling of sulfonated byproducts. The compound’s environmental impact relates primarily to its persistence in water systems rather than fragrance industry concerns.

Explore 2-Naphthalenesulfonic acid, 6-hydroxy-5-[(4-sulfophenyl)azo]-, disodium salt

Browse essential oils and aroma compounds.

Browse on iHerb →

Affiliate disclosure: we may earn a small commission at no extra cost to you.

References

    Data: PubChem (NIH), PubMed, RIFM, IFRA. Last reviewed: Apr 2026.

    Report a data error

    Ingredient Data Sheet

    CAS 2783-94-0

    Physical Properties

    Molecular Weight452.4 g/mol🔬 PubChem
    Boiling Point282 °C🔬 EPA CompTox
    Vapor Pressure0 mmHg @ 25°C📊 OPERA
    SMILESC1=CC(=CC=C1N=NC2=C(C=CC3=C2C=CC(=C3)S(=O)(=O)[O-])O)S(=O)(=O)[O-].[Na+].[Na+]🔬 PubChem

    Volatility & Performance

    Fragrance NoteBase💻 Calculated

    Odor & Flavor

    Functional Groupsphenolaromatic💻 RDKit
    Data Sources & Attribution
    Physical data: PubChem (NIH/NLM), U.S. EPA CompTox Dashboard, EPA OPERA models, RDKit. Odor & flavor: Arctander (Perfume & Flavor Chemicals), Fenaroli's Handbook of Flavor Ingredients, Leffingwell. Thresholds: van Gemert (Compilations of Odour Threshold Values). Regulatory: IFRA Standards 51st, FEMA GRAS. Trade names: Surburg (Common Fragrance & Flavor Materials). All data compiled and cross-referenced for perfumertools.com.

    Physicochemical Properties

    DTXSID: DTXSID6021456

    Physical Properties

    Molecular Weight 452.36 g/mol🔬 EPA CompTox
    Boiling Point 282 °C📊 OPERA
    Melting Point 230 °C📊 OPERA

    Partition & Solubility

    LogP (Octanol-Water) 1.78 Log10 unitless📊 OPERA
    LogD (pH 5.5) 1.52 Log10 unitless📊 OPERA
    LogD (pH 7.4) -0.04 Log10 unitless📊 OPERA
    LogKoa (Octanol-Air) 9.34 Log10 unitless📊 OPERA
    Water Solubility 0.293 mol/L🔬 EPA CTX
    Henry's Law Constant 0 atm-m3/mole📊 OPERA

    Transport Properties

    Vapor Pressure 0 mmHg📊 OPERA

    Molecular Descriptors

    Topological Polar Surface Area 159.35 Ų💻 Computed
    H-Bond Donors 1 count💻 Computed
    H-Bond Acceptors 9 count💻 Computed
    Rotatable Bonds 4 count💻 Computed
    Aromatic Rings 3 count💻 Computed
    Molar Refractivity 92.16 cm^3/mol💻 Computed

    Data Sources:

    🔬 EPA Experimental data from U.S. EPA CompTox Chemicals Dashboard & CTX APIs. 📊 OPERA Predicted using EPA's OPERA QSAR models. 💻 Computed Calculated from SMILES using RDKit.

    Similar Posts