81-16-3

Basic information

• Product Name: 2-Aminonaphthalene-1-sulfonic acid
• Synonyms: TOBIAS ACID;1-Naphthalenesulfonic acid, 2-amino-;1-Naphthalenesulfonicacid,2-amino-;2-amino-1-naphthalenesulfonic;2-amino-1-naphthalenesulfonicaci;Kyselina 2-naftylamin-1-sulfonova;Kyselina tobiasova;kyselina2-naftylamin-1-sulfonova
• CAS NO: 81-16-3
• Molecular Formula: C₁₀H₉NO₃S
• Molecular Weight: 223.25
• EINECS: 201-331-5
• Product Categories: Intermediates of Dyes and Pigments;Intermediates;Organics
• Mol File: 81-16-3.mol
• Article Data: 8

Chemical Properties

• Melting Point: 180 °C
• Boiling Point: 220°C (rough estimate)
• Appearance: /
• Density: 1.3588 (rough estimate)
• Refractive Index: 1.5250 (estimate)
• Storage Temp.: -20°C Freezer, Under inert atmosphere
• Solubility: DMSO (Slightly), Methanol (Slightly, Heated), Water (Slightly, Heated)
• PKA: pK1: 2.35 (25°C)
• Water Solubility: 4.083g/L(20 oC)
• Merck: 14,6406
• BRN: 613084
• CAS DataBase Reference: 2-Aminonaphthalene-1-sulfonic acid(CAS DataBase Reference)
• NIST Chemistry Reference: 2-Aminonaphthalene-1-sulfonic acid(81-16-3)
• EPA Substance Registry System: 2-Aminonaphthalene-1-sulfonic acid(81-16-3)

Safety Data

• Statements: 36/37/38-40
• Safety Statements: 26-36/37/39
• RIDADR: 2585
• WGK Germany: 1
• RTECS: QK1250000
• TSCA: Yes
• HazardClass: 8
• PackingGroup: III
• Hazardous Substances Data: 81-16-3(Hazardous Substances Data)

Usage

Chemical Properties

Grey white to light pink powder

Uses

Different sources of media describe the Uses of 81-16-3 differently. You can refer to the following data:
1. Azo dye intermediate, optical brighteners.
2. 2-Amino-1-naphthalenesulfonic acid has been used in the preparation of 2-(2-naphthylamino)benzoxazole by reacting with 2-chlorobenzoxazole.

General Description

2-Amino-1-naphthalenesulfonic acid is a manufacturing intermediate in the monosulfo monoazo color additive D&C Red No. 34 and its lakes.

Purification Methods

Crystallise the acid under nitrogen from boiling water and dry it in a steam oven [Bryson Trans Faraday Soc 47 522, 527 1951]. [Beilstein 14 III 2240, 14 IV 2792.]

InChI:InChI=1/C10H9NO3S/c11-9-6-5-7-3-1-2-4-8(7)10(9)15(12,13)14/h1-6H,11H2,(H,12,13,14)/p-1

Upstream product

• 567-47-5 2-hydroxy-naphthalene-1-sulfonic acid 
• 7664-41-7 ammonia 
• 110-91-8 morpholine 
• 90-20-0 4-amino-5-hydroxy-2,7-naphthalenedisulfonic acid 
• 112291-51-7 4,5,6-trifluoro-1,2,3-triazine 
• 92-70-6 3-Hydroxy-2-naphthoic acid 
• 91-59-8 naphthalen-2-ylamine 

Downstream Products

• 3737-76-6 Vat Red KKh 
• 135-64-8 3-hydroxy-N-(2-naphthyl)-naphthamide 
• 580-13-2 2-bromonaphthalene 
• 86-60-2 7-aminonaphthalene-1-sulfonic acid 
• 81-05-0 6-aminonaphthalene-1-sulfonic acid 
• 117-62-4 2-amino-1,5-naphthalenedisulfonic acid 
• 7664-93-9 sulfuric acid 
• 20191-75-7 1-bromo-2-naphthylamine 
• 69-72-7 salicylic acid 
• 91-60-1 2-Naphthalenethiol 
• 100514-14-5 3-(2H-Naphtho<1,2-d>triazol-2-yl)benzoesaeure-ethylester 
• 100514-12-3 4-(2H-Naphtho<1,2-d>triazol-2-yl)benzoesaeure-ethylester 
• 65237-05-0 5-amino-4-hydroxy-3-[(1-sulfo-2-naphthyl)azo]naphthalene-2,7-disulfonic acid 
• 1248-18-6 2-[(2-hydroxy-1-naphthalenyl)azo]-1-naphthalenesulfonic acid sodium salt 

Relevant articles and documents

Fibre reactive azo dyestuffs

Fiber reactive azo dyestuffs of the formula STR1 in which R=H or C1 -C6 alkyl, which can be substituted with OH, Hal, SO3 H or OSO3 H; Z=heterocyclic five or six membered ring; n, m=0, 1 or 2, wherein n+m=0, 1 or 2; Y=OH, OR, NR2 R3, OMe; and R2, R3, =H, R and R2, R3 and N can form a heterocyclic 5 or 6-membered ring.

Reactive dye having both monochlorotriazinyl and vinylsulfone type reactive groups

A novel reactive monoazo dye, capable of giving cellulose fiber materials a deep orange to scarlet color and superior in build-up and chlorine fastness properties, represented by a free acid of the formula, STR1 wherein R1 is hydrogen, methyl or ethyl; R2 is an alkyl having 1 to 4 carbons that is either unsubstituted or substituted with hydroxy, cyano, alkoxy, halogen, carboxy, alkoxycarbonyl or sulfonic acid; Z is hydrogen or sulfonic acid; A is phenylene and is either unsubstituted or substituted with 1 or 2 substituents selected from the group consisting of methyl, ethyl, methoxy, ethoxy, chlorine, bromine and sulfonic acid, or natphthylene that is either unsubstituted or substituted with sulfonic acid; X is --SO2 CH=CH2 or --SO2 CH2 CH2 Y in which Y is a group that is splittable by alkalis; and m is an integer of 1 to 3.

Solid phase acylation of aminosulfonic acids

This invention is directed to the acylation of aminosulfonic acids in the solid phase. Two discrete, sequential chemical reactions occur, i.e. (1) the neutralization of the aminosulfonic acid, and (2) the subsequent amine acylation, to produce an improved neutralized acyl-aminosulfonic acid at a reduced cost. Aminosulfonic acids having the general formula HO3 S-A-NH2 are acylated to neutralized acyl-aminosulfonic acids having the general formula RCONH-A-SO3 M, where A is an unsubstituted or substituted aliphatic, aromatic or heteroaromatic group and M is a neutralizing agent moiety. The yield is virtually quantitative.