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Impurities and reference standards

Phthalimide

Also known as Isoindole-1,3-dione, 1H-Isoindole-1,3(2H)-dione, o-Phthalic imide

CAS 85-41-6Formula C8H5NO2Molar mass 147.13 g/molEC 201-603-3
56 suppliers listed
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Phthalimide chemical structure, C8H5NO2, CAS 85-41-6
2D chemical structure

Key facts

What buyers check first

All properties
Appearance
Monoclinic prisms from water or by sublimation
Melting point
238 °C
Boiling point
Sublimes
Solubility
360 mg/l
HS code
292519
Category
Impurities and reference standards
Illustrative photo, closed white HDPE bottles and amber jars on a laboratory bench
Typical packagingIllustrative packaging image, not the actual product

What is Phthalimide?

Plain description, key identifiers and synonyms

Phthalimide is a dicarboximide that is 2,3-dihydro-1H-isoindole substituted by oxo groups at positions 1 and 3.

Identifiers

Registry numbers, names and line notations, tap to copy

IUPAC name
isoindole-1,3-dione
CAS number
85-41-6 CAS number cross-checkedOther or deprecated CAS: 136918-14-4, 223537-84-6
EC numbers
201-603-3, 621-254-4
Molecular formula
C8H5NO2
UNII
1J6PQ7YI80
MDL number
MFCD00005881
InChIKey
XKJCHHZQLQNZHY-UHFFFAOYSA-N
InChI
InChI=1S/C8H5NO2/c10-7-5-3-1-2-4-6(5)8(11)9-7/h1-4H,(H,9,10,11)
SMILES (canonical and isomeric)
C1=CC=C2C(=C1)C(=O)NC2=O

Synonyms

  • Isoindole-1,3-dione
  • 1H-Isoindole-1,3(2H)-dione
  • o-Phthalic imide
  • Benzoimide
  • 1,3-Isoindolinedione
  • 2-Diazoindan-1,3-dione
  • Phenylimide
  • Phthalimid
  • 1,2-Benzenedicarboximide
  • Ftalimmide
  • isoindoline-1,3-dione
  • O-Phthalimide
  • 2,3-dihydro-1H-isoindole-1,3-dione
  • phtalimide
  • 1,3-Dihydroisoindole-1,3-dione
  • 1,3-Isoindoledione
  • 1,3-Dihydro-1,3-dioxoisoindole
  • Epinastine Impurity 17
  • 2H-benzo[c]azoline-1,3-dione
  • Phthalic dicarboximide
  • Phthalimide, Tafenoquine related, SKF-2450
  • isoindoledione
  • Pthalimide
  • phthalimide-
  • hydroxyisoindolone
Show all 35 synonyms
  • folpet TP1
  • hydroxy isoindolone
  • 1,3-dioxoisoindole
  • isoindol-1,3-dione
  • 1,3-Dihydro-2H-isoindole-1,3-dione
  • isoindoline-1,3 dione
  • Phthalimide, >=99%
  • 3-hydroxyisoindol-1-one
  • isoindoline -1,3-dione
  • 1h-isoindole-1,3-dione

Physical and chemical properties

Measured values and descriptors computed from the structure

Physical and chemical properties

Measured values, check the supplier specification for your grade

Appearance
Monoclinic prisms from water or by sublimationexp.
Melting point
238 °Cexp.
Boiling point
Sublimesexp.
Solubility
360 mg/lexp.

Values vary by grade. Ask suppliers for the COA or TDS of the batch you buy.

Computed descriptors

Calculated from the structure, useful for screening and formulation

Molecular weight
147.13 g/molcalc.
Exact mass
147.032 Dacalc.
LogP (octanol/water)
0.57calc.
Topological polar surface area
46.17 Ųcalc.
Hydrogen bond donors
1calc.
Hydrogen bond acceptors
2calc.
Rotatable bonds
0calc.
Heavy atoms
11calc.
Rings
2calc.
Aromatic rings
1calc.
Fraction sp3 carbons
0calc.
Formal charge
0calc.
Stereocentres
0calc.
Lipinski rule of five
Passes (0 violations)calc.

Calculated for screening. Confirm critical figures with the supplier.

Murcko scaffold

The ring system that remains when every side chain is removed

Murcko scaffold of this chemical, O=C1NC(=O)c2ccccc21

O=C1NC(=O)c2ccccc21

2 rings, 11 atoms. This chemical is the scaffold itself.

2,700 other chemicals share this scaffold

Safety and hazards

GHS classification summary, not a safety data sheet

GHS classification
Hazard pictograms

GHS classification summary, not a safety data sheet (SDS). Classifications can differ by supplier, grade and concentration. Always check the supplier's SDS.

Full safety data and first aid

Phthalimide suppliers

Sponsored listings first, then the documented ranking: membership, verification, replies, completeness, freshness and ratings

All 56 suppliers
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Suppliers marked Unclaimed profile have not claimed their profile yet. They are not verified by CompoundList, their offers are price on request and details may have changed, so please confirm them with the supplier. Company representatives can claim a profile with a business email on the company's own website domain. Our team verifies each claim and sends the result by email.

Where suppliers are based

56 suppliers in 10 countries

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Phthalimide price

Indicative price range per kg from live supplier offers

No published prices right now

Suppliers quote this chemical on request. Send one free request and compare quotes side by side.

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Uses and applications

What the substance is used for, by industry and function

In production of phthalocyanine dyes.

In synthesis of primary amines & amino acids in form of its sodium or potassium salt.

Synthetic indigo, via anthranilic acid, fungicide, organic synthesis, laboratory reagent.

Chemical intermediate for primary amines, amino acids, dyes, eg indigo, & folpet (a fungicide).

Inhibitor for oxidation and photochemical reactions.

Industrial uses: Pigment, Intermediate.

Consumer uses: Pigment.

Use classes: Transformation products, Pesticide transformation products.

How it is made

Reaction of phthalic anhydride with ammonium hydroxide or urea

From phthalic anhydride & nh4oh or (nh4)2co3.

Regulatory status

Inventories, regulations and trade controls that list this substance

United States

  • TSCA inventory (USA)
    Status: Active in US commerce

HS code and trade data

Customs classification and reported world trade statistics

Global trade

World import and export statistics for the HS code Phthalimide is traded under.

HS 2925.19Indicative HS code

Imides and their derivatives, salts thereof, other

World exports in 2024
$295M
+11.7% vs 2023, imports $348M
2019 to 2024
Top exporters
  1. China29.7%
  2. Japan22.7%
  3. United Kingdom10.0%
Top importers
  1. United States12.7%
  2. Brazil12.6%
  3. China10.5%
Reported customs values in USD, not prices.Full trade data

The HS code shown for Phthalimide is indicative (it was assigned by structure rules). Confirm the classification with your customs broker before shipping.

Frequently asked questions

Quick answers about Phthalimide, based on the data on this page

What is Phthalimide?

Phthalimide is a dicarboximide that is 2,3-dihydro-1H-isoindole substituted by oxo groups at positions 1 and 3.

What is the CAS number of Phthalimide?

The CAS registry number of Phthalimide is 85-41-6. Other or deprecated CAS numbers: 136918-14-4, 223537-84-6.

What is the molecular formula and weight of Phthalimide?

The molecular formula of Phthalimide is C8H5NO2 and its molar mass is 147.13 g/mol.

What is Phthalimide used for?

In production of phthalocyanine dyes. In synthesis of primary amines & amino acids in form of its sodium or potassium salt. Synthetic indigo, via anthranilic acid, fungicide, organic synthesis, laboratory reagent. Chemical intermediate for primary amines, amino acids, dyes, eg indigo, & folpet (a fungicide).

Is Phthalimide hazardous?

No GHS hazard classification for Phthalimide is recorded on CompoundList yet. That does not prove it is safe. Always read the supplier safety data sheet.

What is the HS code of Phthalimide?

Phthalimide is usually classified under HS code 292519 (Imides and their derivatives, salts thereof, other). This is indicative, confirm it with your customs broker before shipping.

Where can I buy Phthalimide?

CompoundList lists 56 suppliers of Phthalimide in China, India, United States, Germany and 6 more. Send one free request to get and compare quotes. Your contact details stay private until you accept a quote.

Where can I buy Phthalimide in India?

9 suppliers in India list Phthalimide on CompoundList. Filter the suppliers list by country and send a request to compare prices, grades and delivery times.

What is the price of Phthalimide?

Suppliers quote Phthalimide on request because prices depend on grade, purity, quantity and destination. A free request on CompoundList gets you several quotes to compare.

Guides for buyers

Practical guides that help when you source, ship or handle Phthalimide

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Data last updated 7 Oct 2026. Details may have changed, please confirm them with the supplier. Report an error on this page
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