4792-29-4

Basic information

• Product Name: 5-Carboxyphthalide
• Synonyms: 1,3-DIHYDRO-1-OXOISOBENZOFURAN-5-CARBOXYLIC ACID;1-Oxo-5-phthalancarboxylic acid;5-Carboxyl-phthalide;1,3-Dihydro-1-oxoisobenzofuran-5-carboxylic acid, 1,3-Dihydro-1-oxo-2-benzofuran-5-carboxylic acid;5-CARBOXYPHTHALID ACID;5-Carboxyphthalide 97%;5-CARBOXYPHTALIDACID;1-Oxo-1,3-dihydroisobenzofuran-5-carboxylic acid
• CAS NO: 4792-29-4
• Molecular Formula: C₉H₆O₄
• Molecular Weight: 178.14
• EINECS: 225-343-5
• Product Categories: blocks;Carboxes
• Mol File: 4792-29-4.mol
• Article Data: 8

Chemical Properties

• Boiling Point: 481.1 °C at 760 mmHg
• Flash Point: 206.3 °C
• Appearance: White to off white odorless powder
• Density: 1.502
• Vapor Pressure: 4.57E-10mmHg at 25°C
• Refractive Index: 1.635
• PKA: 3.73±0.20(Predicted)
• CAS DataBase Reference: 5-Carboxyphthalide(CAS DataBase Reference)
• NIST Chemistry Reference: 5-Carboxyphthalide(4792-29-4)
• EPA Substance Registry System: 5-Carboxyphthalide(4792-29-4)

Safety Data

• Hazard Codes: Xi,Xn
• Statements: 22
• Hazardous Substances Data: 4792-29-4(Hazardous Substances Data)

Usage

Uses

5-Carboxyphthalide is used in the cosmetic treatment method as a condensation polymer of the cosmetic composition.

Synthesis Reference(s)

The Journal of Organic Chemistry, 36, p. 689, 1971 DOI: 10.1021/jo00804a017

InChI:InChI=1/C9H6O4/c10-8(11)5-1-2-7-6(3-5)4-13-9(7)12/h1-3H,4H2,(H,10,11)

Synthetic route

terephthalic acid (100-21-0) → 5-carboxyphtalide (4792-29-4)

Conditions	Yield
With sulfuric acid; paraformaldehyde In water	82%
With hydrogenchloride; sodium hydroxide; sulfur trioxide In 1,3,5-Trioxan; water
With hydrogenchloride; sodium hydroxide; sulfur trioxide In 1,3,5-Trioxan; water

formaldehyd (50-00-0) + terephthalic acid (100-21-0) → 5-carboxyphtalide (4792-29-4)

Conditions	Yield
With sulfuric acid; sulfur trioxide at 100 - 150℃; for 5 - 6h;	76.4%

chlorosulfuric acid chloromethyl ester (49715-04-0) + terephthalic acid (100-21-0) → 5-carboxyphtalide (4792-29-4)

Conditions	Yield
at 27 - 130℃; for 3h; Product distribution / selectivity; Industry scale; Neat (no solvent);	60%

1-oxo-1,3-dihydroisobenzofuran-5-carboxamide (85118-25-8) → 5-carboxyphtalide (4792-29-4)

Conditions	Yield
With sodium hydroxide anschliessend Ansaeuern;

hydroxymethyl-terephthalic acid (23405-34-7) → 5-carboxyphtalide (4792-29-4)

Conditions	Yield
at 110℃;

2-formyl-4-carboxybenzoic acid (69526-90-5) → 5-carboxyphtalide (4792-29-4)

Conditions	Yield
With sodium hydroxide

phthalide-dicarboxylic acid-(3.5) → 5-carboxyphtalide (4792-29-4)

Conditions	Yield
at 240℃;

5-amino-3H-isobenzofuran-1-one (65399-05-5) → 5-carboxyphtalide (4792-29-4)

Conditions	Yield
Multi-step reaction with 3 steps 1: copper (II)-sulfate; potassium cyanide / ueber eine wss. Diazoniumsalz-Loesung 2: aqueous sulfuric acid 3: aq. NaOH solution / anschliessend Ansaeuern View Scheme

1-oxo-1,3-dihydro-isobenzofuran-5-carbonitrile (82104-74-3) → 5-carboxyphtalide (4792-29-4)

Conditions	Yield
Multi-step reaction with 2 steps 1: aqueous sulfuric acid 2: aq. NaOH solution / anschliessend Ansaeuern View Scheme
With sulfuric acid In water Reflux;

2-dichloromethyl-4-trichloromethyl-benzoyl chloride → 5-carboxyphtalide (4792-29-4)

Conditions	Yield
Multi-step reaction with 2 steps 1: calcium carbonate; water 2: NaOH-solution View Scheme

m-xylene (108-38-3) → 5-carboxyphtalide (4792-29-4)

Conditions	Yield
Multi-step reaction with 6 steps 1: iron chloride; carbon disulfide 2: sodium hypobromite / 0 °C 3: thionyl chloride 5: calcium carbonate; water 6: NaOH-solution View Scheme

2,4-dimethylbenzoyl chloride (21900-42-5) → 5-carboxyphtalide (4792-29-4)

Conditions	Yield
Multi-step reaction with 3 steps 2: calcium carbonate; water 3: NaOH-solution View Scheme

2,4-dimethylacetophenone. (89-74-7) → 5-carboxyphtalide (4792-29-4)

Conditions	Yield
Multi-step reaction with 5 steps 1: sodium hypobromite / 0 °C 2: thionyl chloride 4: calcium carbonate; water 5: NaOH-solution View Scheme

2,4-dimethyl-benzoic acid (611-01-8) → 5-carboxyphtalide (4792-29-4)

Conditions	Yield
Multi-step reaction with 4 steps 1: thionyl chloride 3: calcium carbonate; water 4: NaOH-solution View Scheme

1,3,5-Trioxan (110-88-3) + terephthalic acid (100-21-0) → 5-carboxyphtalide (4792-29-4)

Conditions	Yield
With hydrogenchloride; sodium hydroxide; sulfur trioxide In water
With hydrogenchloride; sulfur trioxide; sodium hydrogencarbonate In water
With hydrogenchloride; sulfur trioxide; sodium hydrogencarbonate In water; acetic acid

1,3,5-Trioxan (110-88-3) + NaHCO3are + terephthalic acid (100-21-0) → 5-carboxyphtalide (4792-29-4)

Conditions	Yield
With hydrogenchloride; sulfur trioxide In water; acetic acid

5-carboxyphtalide (4792-29-4) → 5-(hydroxymethyl)isobenzofuran-1(3H)-one (65006-89-5)

Conditions	Yield
Stage #1: 5-carboxyphtalide With 1,1'-carbonyldiimidazole In tetrahydrofuran at 20℃; for 2h; Stage #2: With sodium tetrahydroborate In tetrahydrofuran; water Stage #3: With hydrogenchloride In tetrahydrofuran; water pH=2;	94%
Multi-step reaction with 2 steps 1: tetrahydrofuran / 2 h / 20 °C 2: sodium tetrahydroborate / tetrahydrofuran; water / 0.08 h / 20 °C View Scheme

5-carboxyphtalide (4792-29-4) + pentafluorophenyl trifloroacetate (14533-84-7) → C15H5F5O4 (1374215-44-7)

Conditions	Yield
With pyridine In tetrahydrofuran at 20℃; for 2h;	93%

5-carboxyphtalide (4792-29-4) → (1-oxo-1,3-dihydroisobenzofuran-5-yl)carbonyl chloride (227954-90-7)

Conditions	Yield
With thionyl chloride; N,N-dimethyl-formamide at 60℃; for 3 - 5h; Product distribution / selectivity; Heating / reflux;	91%
With thionyl chloride
With thionyl chloride In N,N-dimethyl-formamide; toluene
With thionyl chloride In N,N-dimethyl-formamide for 6h; Heating / reflux;
With thionyl chloride; N,N-dimethyl-formamide In toluene at 80℃; for 1h; Heating / reflux;

5-carboxyphtalide (4792-29-4) + methyl iodide (74-88-4) → methyl 1,3-dihydro-1-oxoisobenzofuran-5-carboxylate (23405-32-5)

Conditions	Yield
With potassium carbonate In dimethyl sulfoxide for 0.5h;	91%
With potassium carbonate In N,N-dimethyl-formamide at 50℃;	15%

methanol (67-56-1) + 5-carboxyphtalide (4792-29-4) → methyl 1,3-dihydro-1-oxoisobenzofuran-5-carboxylate (23405-32-5)

Conditions	Yield
With thionyl chloride at 5℃; for 2h; Reflux;	90%

5-carboxyphtalide (4792-29-4) → 1-oxo-1,3-dihydro-isobenzofuran-5-carbonitrile (82104-74-3)

Conditions	Yield
Stage #1: 5-carboxyphtalide With ethyl phosphate; ammonium carbonate In acetonitrile at 0 - 25℃; for 6h; Stage #2: at 90 - 95℃; for 12h;	89.5%
With thionyl chloride; SULFAMIDE In sulfolane; water
With thionyl chloride; SULFAMIDE In sulfolane; water

5-carboxyphtalide (4792-29-4) + butan-1-ol (71-36-3) → 5-butoxycarbonylphthalide

Conditions	Yield
With sulfuric acid In toluene at 80 - 110℃;	88.3%

5-carboxyphtalide (4792-29-4) + 2-Amino-2-methyl-1-propanol (124-68-5) → 4,4-dimethyl-2-(1-oxo-1,3-dihydroisobenzofuran-5-yl)oxazoline (265137-37-9)

Conditions	Yield
Stage #1: 5-carboxyphtalide With chloroformic acid ethyl ester; triethylamine In acetone at -10 - 13℃; for 0.5h; Stage #2: 2-Amino-2-methyl-1-propanol In acetone at -10 - 20℃; Stage #3: With thionyl chloride; ammonia more than 3 stages;	66.8%
Stage #1: 5-carboxyphtalide With thionyl chloride In ISOPROPYLAMIDE at 60 - 80℃; for 6.5h; Stage #2: 2-Amino-2-methyl-1-propanol With potassium carbonate In tetrahydrofuran at 0 - 10℃; for 0.5h; Stage #3: With thionyl chloride; ammonia more than 3 stages;	59.8%

5-carboxyphtalide (4792-29-4) + propan-1-ol-3-amine (156-87-6) → N-(3-hydroxypropyl)-1-oxo-1,3-dihydroisobenzofuran-5-carboxamide (1359020-78-2)

Conditions	Yield
With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; triethylamine In N,N-dimethyl-formamide at 20℃; for 16h;	52%

5-carboxyphtalide (4792-29-4) + C10H14N2O2S*ClH (627898-14-0) → 5-{2-[((2-phenoxyethyl)thio)methyl]-1,3,4-oxadiazol-5-yl}phthalide (627899-11-0)

Conditions	Yield
With tetrachloromethane; triethylamine; 4-(N,N-Dimethylamino)triphenylphosphine In acetonitrile at 20℃;	51%

5-carboxyphtalide (4792-29-4) + thiophenol (108-98-5) → 2-Phenylsulfanylmethyl-terephthalic acid

Conditions	Yield
With potassium carbonate In N,N-dimethyl-formamide

5-carboxyphtalide (4792-29-4) + diluted NaOH-solution → hydroxymethyl-terephthalic acid (23405-34-7)

5-carboxyphtalide (4792-29-4) → methyl 1,3-dihydro-1-oxoisobenzofuran-5-carboxylate (23405-32-5)

Conditions	Yield
Multi-step reaction with 2 steps 1: thionyl chloride 2: methanol View Scheme

5-carboxyphtalide (4792-29-4) → 5-ethoxycarbonylphthalide (23405-31-4)

Conditions	Yield
Multi-step reaction with 2 steps 1: thionyl chloride 2: ethanol View Scheme
With trichlorophosphate In ethanol

5-carboxyphtalide (4792-29-4) → 2-Phenylsulfanylmethyl-terephthaloyl dichloride (67666-77-7)

Conditions	Yield
Multi-step reaction with 2 steps 1: K2CO3 / dimethylformamide 2: SOCl2 View Scheme

Upstream product

• 85118-25-8 1-oxo-1,3-dihydroisobenzofuran-5-carboxamide 
• 65399-05-5 5-amino-3H-isobenzofuran-1-one 
• 82104-74-3 1-oxo-1,3-dihydro-isobenzofuran-5-carbonitrile 
• 49715-04-0 chlorosulfuric acid chloromethyl ester 
• 100-21-0 terephthalic acid 
• 110-88-3 1,3,5-Trioxan 
• 50-00-0 formaldehyd 
• 611-01-8 2,4-dimethyl-benzoic acid 
• 89-74-7 2,4-dimethylacetophenone. 
• 21900-42-5 2,4-dimethylbenzoyl chloride 
• 108-38-3 m-xylene 
• 69526-90-5 2-formylterephthalic acid 
• 23405-34-7 hydroxymethyl-terephthalic acid 

Downstream Products

• 227954-90-7 (1-oxo-1,3-dihydroisobenzofuran-5-yl)carbonyl chloride 
• 23405-32-5 methyl 1-oxo-1,3-dihydro-5-isobenzofurancarboxylate 
• 194785-18-7 6-carboxy-X-rhodamine 
• 1439931-11-9 C₃₅H₃₄N₂O₅ 
• 1374215-44-7 C₁₅H₅F₅O₄ 
• 65006-89-5 5-(hydroxymethyl)isobenzofuran-1(3H)-one 
• 333333-34-9 1-oxo-1,3-dihydroisobenzofuran-5-carbaldehyde 
• 82104-74-3 1-oxo-1,3-dihydro-isobenzofuran-5-carbonitrile 
• 627899-11-0 5-{2-[((2-phenoxyethyl)thio)methyl]-1,3,4-oxadiazol-5-yl}phthalide 
• 23405-31-4 5-ethoxycarbonylphthalide 
• 23405-34-7 hydroxymethyl-terephthalic acid 

Relevant articles and documents

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