3652-92-4

Basic information

• Product Name: 1,3-Dimethyl-1,3-dihydro-2-phenyl-2H-benzimidazole
• Synonyms: 1,3-Dimethyl-1,3-dihydro-2-phenyl-2H-benzimidazole;1,3-Dimethyl-2-phenylbenzimidazoline;1,3-dimethyl-2-pehnylbenzimidazolium cation
• CAS NO: 3652-92-4
• Molecular Formula: C₁₅H₁₆N₂
• Molecular Weight: 224.3
• Mol File: 3652-92-4.mol
• Article Data: 24

Chemical Properties

• Melting Point: 93-94 °C
• Boiling Point: 359.9°C at 760 mmHg
• Flash Point: 160.2°C
• Appearance: /
• Density: 1.095g/cm³
• Vapor Pressure: 2.31E-05mmHg at 25°C
• Refractive Index: 1.601
• PKA: 5.68±0.40(Predicted)
• CAS DataBase Reference: 1,3-Dimethyl-1,3-dihydro-2-phenyl-2H-benzimidazole(CAS DataBase Reference)
• NIST Chemistry Reference: 1,3-Dimethyl-1,3-dihydro-2-phenyl-2H-benzimidazole(3652-92-4)
• EPA Substance Registry System: 1,3-Dimethyl-1,3-dihydro-2-phenyl-2H-benzimidazole(3652-92-4)

Safety Data

• Hazardous Substances Data: 3652-92-4(Hazardous Substances Data)

Usage

General Description

1,3-Dimethyl-1,3-dihydro-2-phenyl-2H-benzimidazole is a chemical compound with the molecular formula C15H16N2. It is a benzimidazole derivative that is commonly used as an intermediate in the synthesis of pharmaceuticals. This chemical exhibits potential antibacterial, antifungal, and antiviral properties, making it a valuable ingredient in the development of new drugs and treatments. Additionally, 1,3-Dimethyl-1,3-dihydro-2-phenyl-2H-benzimidazole has also shown promise in the field of agricultural chemical development, as it can be used as a pesticide or fungicide to protect crops from harmful pathogens. Overall, this chemical compound has a wide range of potential applications and could play a significant role in various industries.

InChI:InChI=1/C15H16N2/c1-16-13-10-6-7-11-14(13)17(2)15(16)12-8-4-3-5-9-12/h3-11,15H,1-2H3

Synthetic route

benzaldehyde (100-52-7) + N,N'-dimethyl-1,2-phenylenediamine (3213-79-4) → 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4)

Conditions	Yield
With copper(II) bis(trifluoromethanesulfonate) In water at 20℃; for 0.0333333h;	100%
With acetic acid In methanol at 20℃; for 0.5h;	86%
With acetic acid In methanol for 0.5h; Ambient temperature;	65%

1,3-dimethyl-2-phenylbenzimidazolium perchlorate → 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4)

Conditions	Yield
With sodium tetrahydroborate In methanol for 1h; Reduction;	90%
With 1-Benzyl-1,4-dihydronicotinamide In water; isopropyl alcohol at 25℃; pH=6; Equilibrium constant; Reduction;

N,N’-dimethyl-2-phenyl-benzo[d]imidazolium iodide (3653-05-2) → 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4)

Conditions	Yield
With methanol; sodium tetrahydroborate at 20℃; for 1h; Inert atmosphere;	89%
With methanol; sodium tetrahydroborate at 0 - 20℃; Inert atmosphere;	77%
With sodium tetrahydroborate In methanol at 20℃; for 0.5h;	70%

1,3-dimethylbenzimidazolium Iodide (7181-87-5) + phenylmagnesium bromide (100-58-3) → 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4)

Conditions	Yield
In tetrahydrofuran for 11h; Heating;	77%

N-methyl-2-(N-methyl-hydrazino)-aniline (858784-83-5) + benzaldehyde (100-52-7) → 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4)

Conditions	Yield
With acetic acid

N-methyl-2-(N-methyl-hydrazino)-aniline (858784-83-5) + benzaldehyde (100-52-7) + acetic acid (64-19-7) → 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4)

benzaldehyde (100-52-7) + N.N'-dimethyl-o-phenylenediamine → 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4)

2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (53088-00-9) + methyl iodide (74-88-4) → 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4)

Conditions	Yield
Stage #1: 2-phenyl-2,3-dihydro-1H-benzoimidazole; methyl iodide With sodium hydroxide In methanol at 110℃; Stage #2: With sodium tetrahydroborate In methanol for 1h; Further stages.;

N,N’-dimethyl-N,N’-di(p-toluenesulfonyl)-o-phenylenediamine (29627-62-1) → 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4)

Conditions	Yield
Multi-step reaction with 2 steps 1: H2O; H2SO4 / 4 h / 85 °C View Scheme
Multi-step reaction with 2 steps 1: conc. sulphuric acid / 4 h / Heating 2: 65 percent / glacial acetic acid / methanol / 0.5 h / Ambient temperature; other aromatic aldehydes View Scheme
Multi-step reaction with 2 steps 1: sulfuric acid / 4 h / 85 °C 2: dichloromethane / 12 h / 0 - 20 °C / Molecular sieve; Inert atmosphere View Scheme

1,2-bis-(p-methylphenylsulfonamido)-benzene (49633-28-5) → 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4)

Conditions	Yield
Multi-step reaction with 3 steps 1: 4 N aq. sodium hydroxide / 0.33 h / Heating 2: conc. sulphuric acid / 4 h / Heating 3: 65 percent / glacial acetic acid / methanol / 0.5 h / Ambient temperature; other aromatic aldehydes View Scheme

2-phenyl-1H-benzoimidazole (716-79-0) → 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4)

Conditions	Yield
Multi-step reaction with 3 steps 1: potassium hydroxide / acetone / 12 h / 50 °C / Heating 2: ethyl acetate / 12 h / 80 °C / Reflux 3: sodium tetrahydroborate / methanol / 0.5 h / 20 °C View Scheme

2-phenyl-1H-benzoimidazole (716-79-0) + methyl iodide (74-88-4) → 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4)

Conditions	Yield
Stage #1: 2-phenyl-1H-benzoimidazole; methyl iodide With sodium hydroxide In methanol at 110℃; for 24h; Inert atmosphere; Sealed tube; Stage #2: With sodium tetrahydroborate In methanol for 1h; Inert atmosphere;

1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4) → 1,3-dimethyl-2-phenylbenzimidazolium perchlorate

Conditions	Yield
With nitrosonium perchlorate In acetonitrile for 0.25h;	86%
With iron(III) perchlorate In acetonitrile	81%
With 1-benzyl-3-carbamoylpyridinium ion In water; isopropyl alcohol at 25℃; pH=6; Equilibrium constant; Kinetics; Further Variations:; Reagents; Oxidation;

1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4) → N-methyl-N-benzamide (13786-09-9)

Conditions	Yield
With oxygen In Petroleum ether for 96h; Mechanism; Ambient temperature; other 1,3-dialkyl-2-arylbenzimidazolines, other solvents, or heating without solvent at different temperatures;	65%
With oxygen In Petroleum ether for 96h; Ambient temperature;	65%

1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4) → 1,3-dimethyl-2-phenylbenzimidazolium tetrafluoroborate

Conditions	Yield
With copper(II) bis(tetrafluoroborate) In acetonitrile for 0.0166667h;	43%
With bis[p-(methyl(2,2,2-trifluoroethyl)amino)]benzhydrylium tetrafluoroborate In acetonitrile at 20℃; Kinetics; Reagent/catalyst; Inert atmosphere;

1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4) + diphenyldisulfane (882-33-7) → 1-methyl-2-phenylbenzimidazole (2622-63-1) + methyl-phenyl-thioether (100-68-5) + thiophenol (108-98-5) + 1,3-Dimethyl-2-phenylbenzenediazolium phenylthiolate

Conditions	Yield
With 2,2'-azobis(isobutyronitrile); 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole In tetrahydrofuran at 61℃; for 10h; Mechanism; Product distribution; also in benzene;	A 6 % Chromat. B 6.4 % Chromat. C 69 % Chromat. D n/a

1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4) + diphenyldisulfane (882-33-7) → 1,3-Dimethyl-2-phenylbenzenediazolium phenylthiolate

Conditions	Yield
With 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole In tetrahydrofuran at 61℃;

1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4) → 1,3-Dimethyl-2-phenylbenzimidazolium 1,1-Dihydro-2,4,6-trinitrocyclohexadienate

Conditions	Yield
With 1,3,5-trinitrobenzene In acetonitrile at 25℃; Rate constant;

1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4) + acetic acid (64-19-7) → 1,3-Dimethyl-2-phenylbenzimidazolium acetate

Conditions	Yield
palladium In acetonitrile at 20℃; for 2h;
palladium diacetate In [D3]acetonitrile at 70℃; for 0.5h; Product distribution / selectivity; Nuclear magnetic resonance (NMR) tube;

1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4) + benzoic acid (65-85-0) → 1,3-dimethyl-2-phenyl-3H-benzoimidazol-1-ium; benzoate

Conditions	Yield
palladium In acetonitrile at 20℃; for 2h;

10-methylacridinium cation (13367-81-2) + 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4) → 9,10-dihydro-10-methylacridine (4217-54-3) + 1,3-dimethyl-2-phenyl-benzoimidazolium (50578-44-4)

Conditions	Yield
In acetonitrile at 24.84℃; Kinetics; Activation energy;

1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4) + carbon dioxide (124-38-9) → carbon monoxide (201230-82-2) + hydrogen (1333-74-0)

Conditions	Yield
With bis(2,9-dimethyl-1,10-phenanthroline)dithiocyanato iron(II); bis[2,9-bis{4-(diphenylphosphanyl)butyl}-4,7-diphenyl-1,10-phenanthroline copper(I)] bis-hexafluorophosphate In acetonitrile at 25℃; for 5h; Reagent/catalyst; Time; UV-irradiation;

1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4) + carbon dioxide (1111-72-4) → hydrogen (1333-74-0) + [13C]Carbon monoxide (1641-69-6)

Conditions	Yield
With bis(2,9-dimethyl-1,10-phenanthroline)dithiocyanato iron(II); bis[2,9-bis{4-(diphenylphosphanyl)butyl}-4,7-diphenyl-1,10-phenanthroline copper(I)] bis-hexafluorophosphate In acetonitrile at 25℃; under 705 Torr; for 5h; Reagent/catalyst; Time; UV-irradiation;

1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4) + N-methyl-2-phenylbenzoxazolium tetra(3,5-dichlorophenyl)borate → C15H15N2(1+)*C24H12BCl8(1-) + C14H13NO

Conditions	Yield
In dimethylsulfoxide-d6; dichloromethane at 60℃; for 2h;

1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (3652-92-4) + N-methyl-2-phenylbenzothiazolium tetra(3,5-dichlorophenyl)borate → 3-Methyl-2-phenyl-2,3-dihydrobenzothiazoline (16192-33-9) + C15H15N2(1+)*C24H12BCl8(1-)

Conditions	Yield
In dimethylsulfoxide-d6; dichloromethane at 60℃; for 2h;

Upstream product

• 858784-83-5 N-methyl-2-(N-methyl-hydrazino)-aniline 
• 100-52-7 benzaldehyde 
• 64-19-7 acetic acid 
• 3213-79-4 N,N'-dimethyl-1,2-phenylenediamine 
• 7181-87-5 1,3-dimethylbenzimidazolium Iodide 
• 100-58-3 phenylmagnesium bromide 
• 3653-05-2 N,N’-dimethyl-2-phenyl-benzo[d]imidazolium iodide 
• 716-79-0 2-phenyl-1H-benzoimidazole 
• 74-88-4 methyl iodide 
• 49633-28-5 1,2-bis-(p-methylphenylsulfonamido)-benzene 
• 29627-62-1 N,N’-dimethyl-N,N’-di(p-toluenesulfonyl)-o-phenylenediamine 
• 53088-00-9 2-phenyl-2,3-dihydro-1H-benzoimidazole 

Downstream Products

• 2622-63-1 1-methyl-2-phenylbenzimidazole 
• 100-68-5 methyl-phenyl-thioether 
• 108-98-5 thiophenol 
• 13786-09-9 N-methyl-N-benzamide 
• 16192-33-9 3-Methyl-2-phenyl-2,3-dihydrobenzothiazoline 
• 1333-74-0 hydrogen 
• 1641-69-6 [13C]Carbon monoxide 
• 4217-54-3 9,10-dihydro-10-methylacridine 
• 50578-44-4 1,3-dimethyl-2-phenyl-benzoimidazolium 

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