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Molekula

Molekula

Thymolphthalein

SKU 40922033 CAS 125-20-2 C28H30O4 MW 430.54 Made to order 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

Thymolphthalein is a pH indicator commonly used in acid-base titrations and in the detection of alkaline substances. It appears as a white to pale yellow crystalline powder and turns blue in basic solutions. Available in powder form with a molecular weight of 430.54 g/mol, its CAS number is 125-20-2, and it is stable at ambient storage conditions. Molekula supplies Thymolphthalein 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 — £24.70 per pack ex VAT · £29.64 inc. VAT
  • 100 g — £62.00 per pack ex VAT · £74.40 inc. VAT

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Specifications

Property Value
Appearance White powder
Melting Point 251-253°C 
Loss on Drying ≤1.0% (100°C)
Solubility Insoluble in water
Infrared Spectrum Conforms
Visual Transition Interval pH 8.8 (colourless) to pH 10.5 (blue)
Absorption maxima 592 - 596 nm

Storage & handling

Property Value
Storage Temperature Ambient
Acidity Neutral

Identification

Property Value
SKU 40922033
CAS Number 125-20-2
IUPAC Name 3,3-bis(4-hydroxy-2-methyl-5-propan-2-ylphenyl)-2-benzofuran-1-one
EC Number 204-729-7
Molecular Formula C28H30O4
Molecular Weight 430.54
Exact Mass 430.2144
SMILES CC1=CC(=C(C=C1C2(C3=CC=CC=C3C(=O)O2)C4=CC(=C(C=C4C)O)C(C)C)C(C)C)O
InChIKey LDKDGDIWEUUXSH-UHFFFAOYSA-N
InChI InChI=1S/C28H30O4/c1-15(2)20-13-23(17(5)11-25(20)29)28(22-10-8-7-9-19(22)27(31)32-28)24-14-21(16(3)4)26(30)12-18(24)6/h7-16,29-30H,1-6H3
PubChem CID 31316
REACH Code Y113
TSCA Listed Yes
HTS Code 29322050
Tariff Code 2932209090

Safety & GHS

Precautionary statements

  • P280 Wear protective gloves/protective clothing/eye protection/face protection

Documents

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-2-methyl-5-(1-methylethyl)phenyl]-
  • 3,3-bis(4-hydroxy-2-methyl-5-propan-2-ylphenyl)-2-benzofuran-1-one
  • 3,3-bis(4-hydroxy-5-isopropyl-2-methyl-phenyl)isobenzofuran-1-one
  • 3,3-bis(4-hydroxy-5-isopropyl-2-methylphenyl)isobenzofuran-1(3H)-one
  • 3,3-Bis(4-hydroxy-5-isopropyl-o-tolyl)phthalide
  • 3,3-Bis[4-hydroxy-2-methyl-5-(1-methylethyl)phenyl]-1(3H)-isobenzofuranone
  • 3,3-bis[4-hydroxy-2-methyl-5-(propan-2-yl)phenyl]-2-benzofuran-1(3H)-one
  • 5',5''-Diisopropyl-2',2''-dimethylphenolphthalein
  • Phenolphthalein, 5',5''-diisopropyl-2',2''-dimethyl-
  • Thymophthalein

Frequently asked questions

What is thymolphthalein used for?

Thymolphthalein is primarily used as a pH indicator in laboratory settings, turning blue in basic solutions (pH 9.3–10.5).

What is the chemical formula and molecular weight of thymolphthalein?

The chemical formula is C28H30O4, and the molecular weight is 430.54 g/mol.

How should thymolphthalein be stored?

Thymolphthalein should be stored at ambient temperature, protected from light and moisture.

What grade of thymolphthalein does Molekula supply?

Molekula supplies thymolphthalein in analytical grade.

Can Molekula supply thymolphthalein in bulk?

Yes, Molekula can supply thymolphthalein in bulk quantities—please contact sales for details.

What documentation comes with a thymolphthalein order?

Each order includes a Certificate of Analysis (CoA) and safety data sheet (SDS) upon request.

Ready to order or need a custom pack?

Tell us the product, grade, and quantity — Molekula usually responds within one working day with pricing and lead time.

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