2138-43-4

Basic information

• Product Name: 4-ISOPROPYLCATECHOL
• Synonyms: 4-ISOPROPYLCATECHOL;4-(1-methylethyl)-2-benzenediol;4-isopropyl-pyrocatecho;Pyrocatechol, 4-isopropyl-;4-isopropylpyrocatechol;PARA-ISOPROPYLCATECHOL;4-Isopropyl-1,2-benzenediol;4-propan-2-ylbenzene-1,2-diol
• CAS NO: 2138-43-4
• Molecular Formula: C₉H₁₂O₂
• Molecular Weight: 152.19
• EINECS: 218-384-5
• Product Categories: Aromatic Phenols
• Mol File: 2138-43-4.mol
• Article Data: 9

Chemical Properties

• Melting Point: 78°C
• Boiling Point: 271°C (estimate)
• Flash Point: 129.2°C
• Appearance: /
• Density: 1.0505 (rough estimate)
• Vapor Pressure: 0.00399mmHg at 25°C
• Refractive Index: 1.4440 (estimate)
• Storage Temp.: -20°C Freezer
• Solubility: Acetonitrile (Slightly), Chloroform (Slightly)
• PKA: 9.86±0.10(Predicted)
• CAS DataBase Reference: 4-ISOPROPYLCATECHOL(CAS DataBase Reference)
• NIST Chemistry Reference: 4-ISOPROPYLCATECHOL(2138-43-4)
• EPA Substance Registry System: 4-ISOPROPYLCATECHOL(2138-43-4)

Safety Data

• Hazardous Substances Data: 2138-43-4(Hazardous Substances Data)

Usage

Uses

4-Isopropylcatechol was used in a catalytic aerobic cross-?dehydrogenative coupling (CDC) reaction with phenols to make aryl ethers.

InChI:InChI=1/C9H12O2/c1-6(2)7-3-4-8(10)9(11)5-7/h3-6,10-11H,1-2H3

Synthetic route

2-hydroxy-5-isopropylbenzaldehyde (68591-07-1) → 4-isopropylcatechol (2138-43-4)

Conditions	Yield
With dihydrogen peroxide In sodium hydroxide for 0.5h; <45 deg C;	85%

4-Isopropylphenol (99-89-8) → 4-isopropylcatechol (2138-43-4)

Conditions	Yield
With 1-hydroxy-3H-benz[d][1,2]iodoxole-1,3-dione In N,N-dimethyl-formamide at 20 - 23℃; for 4h;	69%
Multi-step reaction with 2 steps 1: 40 percent / POCl3 / dimethylformamide / 1 h / Ambient temperature 2: 85 percent / 6percent H2O2 / aq. NaOH / 0.5 h / <45 deg C View Scheme
Stage #1: 4-Isopropylphenol In dichloromethane at 0 - 20℃; for 66h; Stage #2: With lithium aluminium tetrahydride In tetrahydrofuran at 0℃; for 1h; Further stages.;

2,2-dichloro-5-isopropyl-benzo[1,3]dioxole → 4-isopropylcatechol (2138-43-4)

Conditions	Yield
With water

4,4'-(propane-2,2-diyl)bis(benzene-1,2-diol) (18811-78-4) → 4-isopropylcatechol (2138-43-4)

Conditions	Yield
With Menthane; hydrogen; nickel at 180 - 230℃; under 14710.2 - 18387.7 Torr;

1-isopropyl 3,4-dimethoxy benzene (4132-76-7) → 4-isopropylcatechol (2138-43-4)

Conditions	Yield
With hydrogen iodide

benzene-1,2-diol (120-80-9) + isopropyl alcohol (67-63-0) → 4-isopropylcatechol (2138-43-4)

Conditions	Yield
With sulfonated cation exchanger In toluene Heating;

2,2-dichloro-5-isopropyl-benzo[1,3]dioxole + water (7732-18-5) → 4-isopropylcatechol (2138-43-4)

4,4'-(propane-2,2-diyl)bis(benzene-1,2-diol) (18811-78-4) + menthane + hydrogen + nickel catalyst → 4-isopropylcatechol (2138-43-4) + benzene-1,2-diol (120-80-9)

Conditions	Yield
at 180 - 230℃; under 14710.2 - 18387.7 Torr;

3,3,3',3'-tetramethyl-2,3,2',3'-tetrahydro-[1,1']spirobiindene-5,6,5',6'-tetraol (77-08-7) → 4-isopropylcatechol (2138-43-4) + benzene-1,2-diol (120-80-9) + compound C12H16O2 of mp: 135 degree

Conditions	Yield
at 300℃;

5-(1-methylethyl)-1,3-benzodioxole (108303-53-3) → 4-isopropylcatechol (2138-43-4)

Conditions	Yield
Multi-step reaction with 2 steps 1: phosphorus pentachloride 2: water View Scheme

benzene-1,2-diol (120-80-9) + isopropyl alcohol (67-63-0) → 4-isopropylcatechol (2138-43-4) + 3-isopropylbenzene-1,2-diol (2138-48-9)

Conditions	Yield
1-butyl-3-methylimidazolium heptachlorodiindate (III) at 100℃; for 3h; Product distribution / selectivity; In ionic liquid;

4-Isopropylphenol (99-89-8) → 4-isopropylcatechol (2138-43-4) + 4-isopropyl-2-(4-isopropylphenoxy)phenol + 4-isopropyl-3-(4-isopropylphenoxy)phenol

Conditions	Yield
With ammonium bicarbonate In water; acetonitrile at 37℃; Electrochemical reaction;

4-isopropylcatechol (2138-43-4) + epichlorohydrin (106-89-8) → 1,1'-[(4-isopropyl-o-phenylene)dioxy]-bis-(2,3-epoxy-propane) (34646-52-1)

Conditions	Yield
With sodium hydroxide; sodium carbonate In water	76%

4-isopropylcatechol (2138-43-4) + 1,3-Dichloroacetone (534-07-6) → 7-isopropyl-2H-1,5-benzodioxepin-3(4H)-one

Conditions	Yield
With potassium carbonate; sodium iodide In acetone for 4h; Heating;	60%

4-isopropylcatechol (2138-43-4) + (2S,3S,4S,5R,6S)-3,4,5,6-Tetraacetoxy-tetrahydro-pyran-2-carboxylic acid methyl ester (7355-18-2) → 4-Isopropylbrenzcatechin-2-O-triacetyl-β-D-glucopyranosiduronsaeuremethylester (117591-54-5)

Conditions	Yield
With toluene-4-sulfonic acid at 100 - 110℃; under 3 - 6 Torr; for 0.75h;	26%

4-isopropylcatechol (2138-43-4) + benzoyl chloride (98-88-4) → 1,2-bis-benzoyloxy-4-isopropyl-benzene

Conditions	Yield
With pyridine

4-isopropylcatechol (2138-43-4) + dimethyl sulfate (77-78-1) → 1-isopropyl 3,4-dimethoxy benzene (4132-76-7)

Conditions	Yield
With potassium hydroxide

4-isopropylcatechol (2138-43-4) + 3-oxa-1,5-dichloropentane (111-44-4) → 4',5''-Di-isopropyldibenzo-18-crown-6 (110912-22-6) + 4',4''-Di-isopropyldibenzo-18-crown-6 (110912-35-1)

Conditions	Yield
With potassium hydroxide In toluene Title compound not separated from byproducts;

4-isopropylcatechol (2138-43-4) → 4-Isopropyl-o-benzochinon (54210-12-7)

Conditions	Yield
With cerium (IV) sulfate; sulfuric acid In chloroform
With sodium periodate In dichloromethane; water at 20 - 23℃; for 1h;

4-isopropylcatechol (2138-43-4) → 4-Isopropylbrenzcatechin-2-O-β-D-glucopyranosiduronsaeure (117591-56-7)

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / TsOH*H2O / 0.75 h / 100 - 110 °C / 3 - 6 Torr 2: 85 percent / NaOH / H2O / 0.5 h View Scheme

4-isopropylcatechol (2138-43-4) → 4-Isopropylbrenzcatechin-2-O-β-D-glucopyranosiduronsaeuremethylester (117591-55-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: 26 percent / TsOH*H2O / 0.75 h / 100 - 110 °C / 3 - 6 Torr 2: 88 percent / Na, MeOH / 3 h / 20 °C View Scheme

4-isopropylcatechol (2138-43-4) + acetic anhydride (108-24-7) → 4-isopropylphenylene-1,2-diacetate (1039065-26-3)

Conditions	Yield
With pyridine at 20℃;

4-isopropylcatechol (2138-43-4) → C15H14O3

Conditions	Yield
Multi-step reaction with 2 steps 1: sodium periodate / dichloromethane; water / 1 h / 20 - 23 °C 2: oxygen; copper(l) chloride; 4-methoxypyridine / dichloromethane / 20 - 23 °C / 1520.1 Torr / Molecular sieve View Scheme

Upstream product

• 18811-78-4 4,4'-(propane-2,2-diyl)bis(benzene-1,2-diol) 
• 68591-07-1 2-hydroxy-5-isopropylbenzaldehyde 
• 7732-18-5 water 
• 77-08-7 3,3,3',3'-tetramethyl-2,3,2',3'-tetrahydro-[1,1']spirobiindene-5,6,5',6'-tetraol 
• 120-80-9 benzene-1,2-diol 
• 67-63-0 isopropyl alcohol 
• 618-45-1 3-isopropylhydroxybenzene 
• 4132-76-7 1-isopropyl 3,4-dimethoxy benzene 
• 99-89-8 4-Isopropylphenol 
• 108303-53-3 5-(1-methylethyl)-1,3-benzodioxole 

Downstream Products

• 4132-76-7 1-isopropyl 3,4-dimethoxy benzene 
• 34646-52-1 1,1'-[(4-isopropyl-o-phenylene)dioxy]-bis-(2,3-epoxy-propane) 
• 117591-55-6 4-Isopropylbrenzcatechin-2-O-β-D-glucopyranosiduronsaeuremethylester 
• 117591-56-7 4-Isopropylbrenzcatechin-2-O-β-D-glucopyranosiduronsaeure 
• 54210-12-7 4-Isopropyl-o-benzochinon 
• 117591-54-5 4-Isopropylbrenzcatechin-2-O-triacetyl-β-D-glucopyranosiduronsaeuremethylester 

Relevant articles and documents

Chromato–Mass Spectrometric Identification of Unusual Products of 4-Isopropylphenol Oxidation in Aqueous Solutions

4-Isopropylphenol has been chosen as the simplest object to model the processes of oxidation of organic compounds with air oxygen in aqueous media, since it contains a hydrogen atom at the tertiary carbon atom in the α-position with benzene ring and a hydroxyl group enabling mass-spectrometric detection of the products in the negative ions mode. It has been stated that oxidation of 4-isopropylphenol with air oxygen in aqueous media becomes noticeable as the solution pH approaches the рKа value of the substrate (10.25). The major product [4-isopropyl-2-(4-isopropylphenoxy)phenol] is formed via nucleophilic addition of the starting 4-isopropylphenol at the intermediate product of its oxidation, quinone methide. Intensity of electrochemical oxidation can be tubed by changing the electrode potential. The highest conversion of 4-isopropylphenol has been observed at potential 1.5–3.0 V, the formed compounds being the products of transformation of the same quinone methide intermediate. The obtained data have explained the formation and diversity of dimeric and oligomeric products of oxidation of natural flavonoids.

Iron-catalyzed arene C-H hydroxylation

The sustainable, undirected, and selective catalytic hydroxylation of arenes remains an ongoing research challenge because of the relative inertness of aryl carbon-hydrogen bonds, the higher reactivity of the phenolic products leading to over-oxidized by-products, and the frequently insufficient regioselectivity. We report that iron coordinated by a bioinspired L-cystine-derived ligand can catalyze undirected arene carbon-hydrogen hydroxylation with hydrogen peroxide as the terminal oxidant. The reaction is distinguished by its broad substrate scope, excellent selectivity, and good yields, and it showcases compatibility with oxidation-sensitive functional groups, such as alcohols, polyphenols, aldehydes, and even a boronic acid. This method is well suited for the synthesis of polyphenols through multiple carbon-hydrogen hydroxylations, as well as the late-stage functionalization of natural products and drug molecules.

Efficient ortho-oxidation of phenols with diacyl peroxides

A stable symmetric diacyl peroxide, m-chlorobenzoyl peroxide (mCBPO), and an asymmetric diacyl peroxide, chloroacetyl m-chlorobenzoyl peroxide (CAMCBPO), were synthesized from m-chloroperbenzoic acid. Both peroxides oxidized phenols selectively at the ortho position predoninantly. CAMCBPO gave para-oxidized compounds as minor products from some phenols. The improvement of the yield of ortho-oxidation of phenols with mCBPO was also reported.