Phthalic acid - ACS, ≥99.5% , CAS No.88-99-3

CAS: 88-99-3 Cat. No.: P104115 Formula: C8H6O4 Molecular Weight: 166.13 Beilstein Registry Number: 608199 EC Number: 201-873-2
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GRADE & PURITY ACS ? ACS grade — meets American Chemical Society specifications, the analytical benchmark in the US. Use for analytical and QC work needing ACS-defined purity. ≥99.5%
Synonyms
1,2-benzenedicarboxylic acid | o-dicarboxybenzene | benzene-1,2-dicarboxylic acid | o-benzenedicarboxylic acid | o-phthalic acid
Storage
Room temperature
Shipped In
Normal
★
Size
USA
Germany (EU)*
Price
Qty
100g
P104115-100g
5 In stock
—
$30.90
500g
P104115-500g
1 In stock
1 In stock
$103.90
Enter a quantity for the sizes you want to add.
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Why this grade

ACS, ≥99.5% ACS for sensitive chromatographic and analytical workflows requiring minimal baseline interference.

🌡

Storage & shipping

Room temperature Ships Normal Check lot-specific COA for exact specifications.

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Quality documents

SDS, COA, datasheet, and spec sheet available for download. Lot-specific COA accessible via lot number lookup.

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Literature proof

Cited in 126 peer-reviewed publications across chromatography, organic synthesis, and cross-coupling reactions.

Overview

Phthalic acid (PA, PTA), also called as 1,2-benzenedicarboxylic acid is an aromatic carboxylic acid. It is the ortho form of the three phthalic acid isomers, the other two being isophthalic acid (meta form) and terephthalic acid (para form). PA is the starting material in the synthesis of plasticizers. A study on toxicity reveals that PA shows in vitro and in vivo toxicity. Its mineralization by photocatalysis using TiO2/UV system has been studied. It also is used as a potential tyrosinase inhibitor.

 
Application:
Phthalic acid may be used as a catalyst for the thiocyanation of aromatics and heteroaromatics and as an interfacial protector for the preparation of ordered mesoporous γ-alumina. It may be used as a model compound in understanding the adsorption of aromatic carboxylic acids on gold surfaces.

Specifications

Synonyms
1,2-benzenedicarboxylic acid | o-dicarboxybenzene | benzene-1,2-dicarboxylic acid | o-benzenedicarboxylic acid | o-phthalic acid
Specifications & Purity
ACS, ≥99.5%
Storage
Room temperature
Shipped In
Normal
Grade
ACS
Purity
≥99.5%
Names and Identifiers
Canonical Smiles
C1=CC=C(C(=C1)C(=O)O)C(=O)O
IUPAC Name
phthalic acid
InChIKey
XNGIFLGASWRNHJ-UHFFFAOYSA-N
INCHI
1S/C8H6O4/c9-7(10)5-3-1-2-4-6(5)8(11)12/h1-4H,(H,9,10)(H,11,12)
Isomeric SMILES
C1=CC=C(C(=C1)C(=O)O)C(=O)O
WGK Germany
1
RTECS
TH9625000
Molecular Weight
166.13
Beilstein
608199
Reaxy-Rn
608199
Reaxys-RN_link_address
https://www.reaxys.com/reaxys/secured/hopinto.do?context=S&query=IDE.XRN=608199&ln=

Documentation

📋 Safety Data Sheet (SDS)

Comprehensive hazard, handling, storage, and regulatory compliance document.

Download SDS →

✅ Certificate of Analysis (COA)

Lot-specific quality data. Enter your lot number to retrieve the exact COA.

Look up COA →

📊 Datasheet

Quick-reference summary of product specifications and applications.

View datasheet →

🔬 Specification Sheet

Full quality attributes and acceptance criteria for this grade.

View spec sheet →

Advanced Data

Taxonomic Classification

Taxonomy Tree

KingdomOrganic compounds
SuperclassBenzenoids
ClassBenzene and substituted derivatives
SubclassBenzoic acids and derivatives
Intermediate Tree Nodes Not available
Direct ParentBenzoic acids
Alternative Parents Benzoyl derivatives  Dicarboxylic acids and derivatives  Carboxylic acids  Organooxygen compounds  Organic oxides  Hydrocarbon derivatives  
Molecular FrameworkAromatic homomonocyclic compounds
Substituents Benzoic acid - Benzoyl - Dicarboxylic acid or derivatives - Carboxylic acid - Carboxylic acid derivative - Organic oxygen compound - Organic oxide - Hydrocarbon derivative - Organooxygen compound - Aromatic homomonocyclic compound
DescriptionThis compound belongs to the class of organic compounds known as benzoic acids. These are organic Compounds containing a benzene ring which bears at least one carboxyl group.
External Descriptors benzenedicarboxylic acid
3D Structure
Interactive Chemical Structure Model





Associated Targets(Human)
ESR1 Tclin Estrogen receptor alpha (17718 Activities)
Activity TypeRelationActivity valueUnitsAction TypeJournalPubMed IddoiAssay Aladdin ID
PPARG Tclin Peroxisome proliferator-activated receptor gamma (15191 Activities)
Activity TypeRelationActivity valueUnitsAction TypeJournalPubMed IddoiAssay Aladdin ID
LCK Tclin Tyrosine-protein kinase LCK (9212 Activities)
Activity TypeRelationActivity valueUnitsAction TypeJournalPubMed IddoiAssay Aladdin ID
ALDH1A1 Tchem Aldehyde dehydrogenase 1A1 (77053 Activities)
Activity TypeRelationActivity valueUnitsAction TypeJournalPubMed IddoiAssay Aladdin ID
ALOX15 Tchem Arachidonate 15-lipoxygenase (7108 Activities)
Activity TypeRelationActivity valueUnitsAction TypeJournalPubMed IddoiAssay Aladdin ID
TDP1 Tchem Tyrosyl-DNA phosphodiesterase 1 (345557 Activities)
Activity TypeRelationActivity valueUnitsAction TypeJournalPubMed IddoiAssay Aladdin ID
CBX1 Tbio Chromobox protein homolog 1 (92434 Activities)
Activity TypeRelationActivity valueUnitsAction TypeJournalPubMed IddoiAssay Aladdin ID
BAZ2B Tchem Bromodomain adjacent to zinc finger domain protein 2B (56204 Activities)
Activity TypeRelationActivity valueUnitsAction TypeJournalPubMed IddoiAssay Aladdin ID
SLCO2B1 Tchem Solute carrier organic anion transporter family member 2B1 (580 Activities)
Activity TypeRelationActivity valueUnitsAction TypeJournalPubMed IddoiAssay Aladdin ID
Associated Targets(non-human)
Plasmodium falciparum (966862 Activities)
Activity TypeRelationActivity valueUnitsAction TypeJournalPubMed IddoiAssay Aladdin ID
Mus musculus (284745 Activities)
Activity TypeRelationActivity valueUnitsAction TypeJournalPubMed IddoiAssay Aladdin ID
GCN5 Histone acetyltransferase GCN5 (89 Activities)
Activity TypeRelationActivity valueUnitsAction TypeJournalPubMed IddoiAssay Aladdin ID
Rorc Nuclear receptor ROR-gamma (89407 Activities)
Activity TypeRelationActivity valueUnitsAction TypeJournalPubMed IddoiAssay Aladdin ID
Mechanisms of Action
Certificates(CoA,COO,BSE/TSE and Analysis Chart)
C of A & Other Certificates(BSE/TSE, COO):
Analytical Chart:

Find and download the COA for your product by matching the lot number on the packaging.

21 results found

Lot NumberCertificate TypeDateItem
F2626157Certificate of AnalysisJun 13, 2026 P104115
F2626155Certificate of AnalysisJun 13, 2026 P104115
L2517458Certificate of AnalysisNov 29, 2025 P104115
H2508531Certificate of AnalysisJul 10, 2025 P104115
K2519097Certificate of AnalysisJul 10, 2025 P104115
H2508529Certificate of AnalysisJul 10, 2025 P104115
A2516252Certificate of AnalysisDec 26, 2024 P104115
A2516253Certificate of AnalysisDec 26, 2024 P104115
K2415409Certificate of AnalysisNov 01, 2024 P104115
I2409418Certificate of AnalysisSep 14, 2024 P104115
I2418575Certificate of AnalysisAug 22, 2024 P104115
I2426431Certificate of AnalysisAug 22, 2024 P104115
F2425299Certificate of AnalysisJun 07, 2024 P104115
K2324214Certificate of AnalysisNov 13, 2023 P104115
K2324215Certificate of AnalysisNov 13, 2023 P104115
B2323572Certificate of AnalysisAug 30, 2022 P104115
J2215369Certificate of AnalysisAug 30, 2022 P104115
J2215371Certificate of AnalysisAug 30, 2022 P104115
B2303869Certificate of AnalysisAug 30, 2022 P104115
G2220630Certificate of AnalysisJun 15, 2022 P104115
G2220631Certificate of AnalysisJun 15, 2022 P104115
Chemical and Physical Properties
SensitivityMoisture sensitive.
Melt Point(°C)210-211°C
Molecular Weight166.130 g/mol
XLogP30.700
Hydrogen Bond Donor Count2
Hydrogen Bond Acceptor Count4
Rotatable Bond Count2
Exact Mass166.027 Da
Monoisotopic Mass166.027 Da
Topological Polar Surface Area74.600 Ų
Heavy Atom Count12
Formal Charge0
Complexity177.000
Isotope Atom Count0
Defined Atom Stereocenter Count0
Undefined Atom Stereocenter Count0
Defined Bond Stereocenter Count0
Undefined Bond Stereocenter Count0
The total count of all stereochemical bonds0
Covalently-Bonded Unit Count1
Documents & Articles
Citations of This Product
Solution Calculators
Reviews

Customer Reviews

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