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Molekula

Molekula

o-Cresolphthalein

SKU 15685521 CAS 596-27-0 C22H18O4 MW 346.38 In stock (5+ packs) — same-day dispatch Bulk quantities on request

Supplying 4,500+ customers in over 80 countries

ISO 9001:2015 & ISO 14001:2015 certified · Supplying laboratories and industry since 2000 · Listed pack sizes are a starting point — we manufacture, source and repack to the quantity you need

o-Cresolphthalein is a synthetic organic compound primarily used as a pH indicator in analytical chemistry, particularly for detecting alkaline solutions (pH 8.2–9.8). It appears colorless in acidic and neutral conditions but turns bright pink in strongly basic environments, making it ideal for titrations and laboratory testing. This chemical has a CAS number of 596-27-0, with the molecular formula C22H18O4 and a molecular weight of 346.38. It is stable at ambient storage conditions and carries no signal word for hazard classification. Molekula supplies o-Cresolphthalein from research to bulk quantities with full documentation and ISO 9001:2015 traceability.

Expect a response within hours Speak to a chemist: +44 (0) 3302 000333

Example image for illustration only. Other packaging and pack sizes are available.

Pricing & pack sizes

Pack sizes & pricing

These pack sizes aren't a limit. Molekula manufactures, sources and repacks to order — if you need 500 kg and only see 1 kg listed, . We quote from grams to multi-tonne.

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  • 25 g — $88.40 per pack

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Specifications

Property Value
Appearance Beige/Cream to yellow powder
Identification Conforms to reference
pH 6.0-7.0
Solubility test in ethanol Complies
pH Transition - Colour Change 8.2 (colorless) to 9.8 (red)

Storage & handling

Property Value
Storage Temperature Ambient
Acidity Neutral

Identification

Property Value
SKU 15685521
CAS Number 596-27-0
IUPAC Name 3,3-bis(4-hydroxy-3-methylphenyl)-2-benzofuran-1-one
Molecular Formula C22H18O4
Molecular Weight 346.38
Exact Mass 346.1205
SMILES CC1=C(C=CC(=C1)C2(C3=CC=CC=C3C(=O)O2)C4=CC(=C(C=C4)O)C)O
InChIKey CPBJMKMKNCRKQB-UHFFFAOYSA-N
InChI InChI=1S/C22H18O4/c1-13-11-15(7-9-19(13)23)22(16-8-10-20(24)14(2)12-16)18-6-4-3-5-17(18)21(25)26-22/h3-12,23-24H,1-2H3
PubChem CID 68995
REACH Code Y113
TSCA Listed Yes
HTS Code 29322045
Tariff Code 2932209090

Safety & GHS

Precautionary statements

  • P280 Wear protective gloves/protective clothing/eye protection/face protection
  • P410+403 Protect from sunlight. Store in a well ventilated place

Documents

Safety Data Sheets (SDS)

Available in English, French, German, Italian, Spanish.

Certificate of Analysis (CoA) by batch

Enter a lot or batch number to retrieve the CoA for that specific batch. We can generate one from spec data if no PDF is on file.

Synonyms

  • 1(3H)-Isobenzofuranone, 3,3-bis(4-hydroxy-3-methylphenyl)-
  • 3,3-bis(4-hydroxy-3-methyl-phenyl)isobenzofuran-1-one
  • 3,3-Bis(4-hydroxy-3-methylphenyl)-1(3H)-isobenzofuranone
  • 3,3-bis(4-hydroxy-3-methylphenyl)-2-benzofuran-1-one
  • 3,3-bis(4-hydroxy-3-methylphenyl)-3-hydroisobenzofuran-1-one
  • 3,3-Bis(4-hydroxy-3-methylphenyl)isobenzofuran-1(3H)-one
  • 3,3'-Dimethylphenolphthalein
  • Cresolphthalein
  • CRESOLPHTHALEIN, O-
  • Phenolphthalein, 3',3''-dimethyl-

Frequently asked questions

What is o-Cresolphthalein commonly used for?

o-Cresolphthalein is primarily used as a pH indicator in analytical chemistry, particularly for detecting alkaline solutions (color change from colorless to pink/red in pH 8.3–10.0). It is also used in titrations.

What is the chemical formula and molecular weight of o-Cresolphthalein?

The chemical formula is C₂₂H₁₈O₄, and the molecular weight is 346.38 g/mol.

How should o-Cresolphthalein be stored?

Store o-Cresolphthalein at ambient temperature in a tightly sealed container, protected from light and moisture. No special refrigeration is required.

What grades or purity levels of o-Cresolphthalein does Molekula supply?

Molekula supplies analytical reagent (AR) grade o-Cresolphthalein, meeting high-purity standards for laboratory and analytical applications.

Can Molekula supply o-Cresolphthalein in bulk quantities?

Yes, Molekula can provide o-Cresolphthalein in bulk quantities upon request, with flexible packaging options (e.g., drums, bottles) depending on order size.

What documentation is provided with an order of o-Cresolphthalein?

Each order includes a Certificate of Analysis (CoA), Material Safety Data Sheet (MSDS), and batch-specific documentation to verify purity and compliance with specifications.

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