25596-24-1

Basic information

• Product Name: TRIMETHYLSULFOXONIUM BROMIDE
• Synonyms: TRIMETHYLSULFOXONIUM BROMIDE;TriMethylsulfoxoniuM BroMide, 98.0%(T)
• CAS NO: 25596-24-1
• Molecular Formula: Br*C₃H₉OS
• Molecular Weight: 173.07
• Product Categories: Iodonium Sulfonium & Oxonium Compounds;Sulfonium Compounds;Sulfur Compounds (for Synthesis);Synthetic Organic Chemistry
• Mol File: 25596-24-1.mol

Chemical Properties

• Appearance: /
• Density: 1.440 (estimate)
• Storage Temp.: Inert atmosphere,Room Temperature
• CAS DataBase Reference: TRIMETHYLSULFOXONIUM BROMIDE(CAS DataBase Reference)
• NIST Chemistry Reference: TRIMETHYLSULFOXONIUM BROMIDE(25596-24-1)
• EPA Substance Registry System: TRIMETHYLSULFOXONIUM BROMIDE(25596-24-1)

Safety Data

• Safety Statements: 24/25
• Hazardous Substances Data: 25596-24-1(Hazardous Substances Data)

Usage

Uses

Used in Organic Synthesis:
Trimethylsulfoxonium bromide is used as a reagent for the preparation of sulfoxides and sulfonium salts, which are important intermediates in the synthesis of various organic compounds.
Used in the Generation of Reactive Species:
It is used as a source of trimethylsulfonium cation for the generation of reactive sulfonium ylides, which are valuable in organic reactions, particularly in the formation of carbon-carbon bonds.
Used in Pharmaceutical Industry:
Trimethylsulfoxonium bromide is used as a methylating agent in the synthesis of pharmaceutical compounds, aiding in the modification of drug molecules to enhance their properties and effectiveness.
Used in Chemical Research:
In the field of chemical research, it is employed for studying the reactivity and properties of organosulfur compounds, contributing to the advancement of organic chemistry knowledge and techniques.

InChI:InChI=1/C3H9OS.BrH/c1-5(2,3)4;/h1-3H3;1H/q+1;/p-1

Synthetic route

methyl bromide (74-83-9) + dimethyl sulfoxide (67-68-5) → trimethyloxosulfonium bromide (25596-24-1)

beryllium(II) chloride (7787-47-5) + trimethyloxosulfonium bromide (25596-24-1) → tetrakis(dimethylsulfoxonium methylide)beryllium dichloride

Conditions	Yield
With sodium hydride In tetrahydrofuran THF soln. of Me2SOCH2 prepd. from mixt. of Me3SO(1+)Br(1-) and NaH in dry THF, to this soln. added BeCl2, stirred for 5 d at room temp.; pptd. complex filtered, washed with pentane, dried under vac.; elem. anal.;	88.8%

(triphenylphosphine)gold(I) chloride (14243-64-2) + trimethyloxosulfonium bromide (25596-24-1) → bis(dimethylsulfoxonium methylide)gold(I) chloride (111800-89-6, 110923-62-1)

Conditions	Yield
With sodium hydride In tetrahydrofuran byproducts: hydrogen; Me2SOCH2 prepd. by refluxing mixt. of Me3SO(1+)Br(1-) and NaH in dry THF under N2 until evolution of H2 ceased, cooled, filtered under N2, to resulting soln. added Ph3PAuCl, stirred for 3 h at room temp.; pptd. complex filtered, washed with dry pentane, dried under vac.; elem. anal.;	85.5%

3,5-diacetoxybenzaldehyde (57179-37-0) + trimethyloxosulfonium bromide (25596-24-1) → C12H12O5

Conditions	Yield
With potassium tert-butylate In dimethyl sulfoxide at 60℃; for 5.33333h;	85.1%

vitamin B12 + trimethyloxosulfonium bromide (25596-24-1) → methylcobalamin

Conditions	Yield
Stage #1: vitamin B12 With sodium tetrahydroborate; cobalt(II) chloride In water; butanone at 30 - 50℃; for 1.5 - 2.5h; Stage #2: trimethyloxosulfonium bromide at 15 - 50℃;	85%

cyanocobalamin (68-19-9) + trimethyloxosulfonium bromide (25596-24-1) → CH3Cb1 (13422-55-4)

Conditions	Yield
Stage #1: cyanocobalamin With sodium tetrahydroborate; cobalt(II) chloride In water; butanone at 30 - 50℃; for 1.66667 - 2.5h; Stage #2: trimethyloxosulfonium bromide In water; butanone at 15 - 50℃;	85%

trimethyloxosulfonium bromide (25596-24-1) + 2-chlorobenzyl 4-fluorophenyl ketone (150344-44-8) → C15H12ClFO

Conditions	Yield
Stage #1: trimethyloxosulfonium bromide With sodium hydroxide In dimethyl sulfoxide at 0 - 20℃; for 0.5h; Stage #2: 2-chlorobenzyl 4-fluorophenyl ketone In dimethyl sulfoxide at 40℃; for 12h;	85%

C14H9BrClFO + trimethyloxosulfonium bromide (25596-24-1) → C15H11BrClFO

Conditions	Yield
Stage #1: trimethyloxosulfonium bromide With sodium hydride In dimethyl sulfoxide at 0 - 20℃; for 0.5h; Stage #2: C14H9BrClFO In dimethyl sulfoxide at 40℃; for 12h;	85%

5-[(4-chlorophenyl)methyl]-2,2-dimethylcyclopentanone (115851-28-0) + sodium triazole (41253-21-8) + trimethyloxosulfonium bromide (25596-24-1) → metconazole (125116-23-6)

Conditions	Yield
With sodium hydroxide In 1-methyl-pyrrolidin-2-one at 110℃; for 5h; Reagent/catalyst; Solvent; Temperature; Flow reactor; Inert atmosphere;	85%

2-(4-chlorobenzyl)-8,8-dimethyl-7,9-dioxaspiro[4,5]decan-1-one + sodium triazole (41253-21-8) + trimethyloxosulfonium bromide (25596-24-1) → 2-(4-chlorobenzyl)-8,8-dimethyl-1-(1H-1,2,4-triazol-1-yl methyl)-7,9-dioxaspiro[4,5]decan-1-ol (1447648-36-3)

Conditions	Yield
With sodium hydroxide In N,N-dimethyl acetamide; water at 65 - 85℃; for 9h; Reagent/catalyst; Time; Temperature;	82%
Stage #1: 2-(4-chlorobenzyl)-8,8-dimethyl-7,9-dioxaspiro[4,5]decan-1-one; sodium triazole; trimethyloxosulfonium bromide In N,N-dimethyl acetamide at 85℃; for 0.833333h; Stage #2: With sodium methylate In methanol; N,N-dimethyl acetamide for 0.833333h; Reagent/catalyst;	78.2%

ethyl (2E)-3-[3-{[(tert-butoxycarbonyl)amino]methyl}-4-(4-methylphenyl)-2-propylquinolin-6-yl]acrylate (660450-65-7) + trimethyloxosulfonium bromide (25596-24-1) → ethyl 2-[3-{[(tert-butoxycarbonyl)amino]methyl}-4-(4-methylphenyl)-2-propylquinolin-6-yl]cyclopropane-1-carboxylate (660450-87-3)

Conditions	Yield
Stage #1: trimethyloxosulfonium bromide With sodium hydride In dimethyl sulfoxide at 20℃; for 1h; Stage #2: ethyl (2E)-3-[3-{[(tert-butoxycarbonyl)amino]methyl}-4-(4-methylphenyl)-2-propylquinolin-6-yl]acrylate In dimethyl sulfoxide at 20℃; for 1h;	81%

1,2,4-Triazole (288-88-0) + 2-(4-chlorobenzyl)-8,8-dimethyl-7,9-dioxaspiro[4,5]decan-1-one + trimethyloxosulfonium bromide (25596-24-1) → 2-(4-chlorobenzyl)-8,8-dimethyl-1-(1H-1,2,4-triazol-1-yl methyl)-7,9-dioxaspiro[4,5]decan-1-ol (1447648-36-3)

Conditions	Yield
Stage #1: 1,2,4-Triazole With sodium methylate In methanol; N,N-dimethyl acetamide at 85℃; for 3h; Stage #2: 2-(4-chlorobenzyl)-8,8-dimethyl-7,9-dioxaspiro[4,5]decan-1-one; trimethyloxosulfonium bromide In methanol; N,N-dimethyl acetamide at 85℃; for 1.66667h; Reagent/catalyst; Temperature; Solvent;	78.1%
Stage #1: 1,2,4-Triazole With sodium hydride In 1-methyl-pyrrolidin-2-one; mineral oil for 0.5h; Stage #2: 2-(4-chlorobenzyl)-8,8-dimethyl-7,9-dioxaspiro[4,5]decan-1-one; trimethyloxosulfonium bromide With sodium t-butanolate In 1-methyl-pyrrolidin-2-one; mineral oil at 90 - 125℃; for 4h;	74.3%

2-(4-chlorobenzyl)-5-(1-methylethyl)cyclopentanone + sodium triazole (41253-21-8) + trimethyloxosulfonium bromide (25596-24-1) → ipconazole (125225-28-7)

Conditions	Yield
With sodium hydroxide In 1-methyl-pyrrolidin-2-one at 100℃; for 11h; Flow reactor;	78%

indium(III) chloride (10025-82-8) + trimethyloxosulfonium bromide (25596-24-1) → μ-chloro-bis{tris(dimethylsulfoxonium methylide)indium} pentachloride

Conditions	Yield
With sodium hydride In tetrahydrofuran THF soln. of Me2SOCH2 prepd. from mixt. of Me3SO(1+)Br(1-) and NaH in dry THF under N2, InCl3 added to this soln., stirred for 3 d at room temp.; pptd. complex filtered, washed with pentane, dried; elem. anal.;	72.5%

1,2,4-Triazole (288-88-0) + 5-[(4-chlorophenyl)methyl]-2,2-dimethylcyclopentanone (115851-28-0) + trimethyloxosulfonium bromide (25596-24-1) → metconazole (125116-23-6)

Conditions	Yield
Stage #1: 1,2,4-Triazole With sodium hydroxide In 1-methyl-pyrrolidin-2-one; toluene at 125℃; Stage #2: 5-[(4-chlorophenyl)methyl]-2,2-dimethylcyclopentanone; trimethyloxosulfonium bromide In 1-methyl-pyrrolidin-2-one; toluene at 115℃; for 6h;	72.03%
With sodium hydroxide In ISOPROPYLAMIDE; water; toluene
Stage #1: 1,2,4-Triazole; trimethyloxosulfonium bromide With sodium hydride In 1-methyl-pyrrolidin-2-one for 0.5h; Stage #2: 5-[(4-chlorophenyl)methyl]-2,2-dimethylcyclopentanone In 1-methyl-pyrrolidin-2-one; tert-Amyl alcohol at 100℃; for 4h;	4.37 g

5-(4-chlorobenzyl)-2-methoxymethoxymethyl-2-methylcyclopentanone (1311402-65-9) + sodium triazole (41253-21-8) + trimethyloxosulfonium bromide (25596-24-1) → 5-(4-chlorobenzyl)-2-methoxymethoxymethyl-2-methyl-1-(1H-1,2,4-triazole-1-ylmethyl)cyclopentanol (1311402-66-0)

Conditions	Yield
With sodium t-butanolate In 1-methyl-pyrrolidin-2-one at 115℃; for 4.25h;	71%
With 1-methyl-pyrrolidin-2-one; sodium t-butanolate In water at 115℃; for 4.25h;	71%
With sodium t-butanolate In 1-methyl-pyrrolidin-2-one at 115℃; for 4.25h;

aluminium trichloride (7446-70-0) + trimethyloxosulfonium bromide (25596-24-1) → μ-chloro-bis{tris(dimethylsulfoxonium methylide)aluminium} pentachloride

Conditions	Yield
With sodium hydride In tetrahydrofuran THF soln. of Me2SOCH2 prepd. from mixt. of Me3SO(1+)Br(1-) and NaH in dry THF under N2, AlCl3 added to this soln., stirred for 3 d at room temp.; pptd. complex filtered under N2, washed with pentane, dried under vac.; elem. anal.;	61.5%

Gallium trichloride (13450-90-3) + trimethyloxosulfonium bromide (25596-24-1) → μ-chloro-bis{tris(dimethylsulfoxonium methylide)gallium} pentachloride

Conditions	Yield
With sodium hydride In tetrahydrofuran THF soln. of Me2SOCH2 prepd. from mixt. of Me3SO(1+)Br(1-) and NaH in dry THF under N2, GaCl3 added to this soln., stirred for 1 d at room temp.; pptd. complex filtered, washed with pentane under N2, dried under vac.; elem. anal.;	57.4%

sodium triazole (41253-21-8) + methyl 2-(2-chloro-4-((5-chloropyridine-2-yl)oxy)phenyl)-2-oxoacetate + trimethyloxosulfonium bromide (25596-24-1) → methyl 2-(2-chloro-4-((5-chlorobenzyl-2-yl)oxy)phenyl)-2-hydroxy-3-(1H-1,2,4-triazol-1-yl)propanoate

Conditions	Yield
In N,N-dimethyl acetamide at 50℃; for 3h;	42.3%

methyl 2-(2-chloro-5-(4-chlorophenoxy)phenyl)-2-oxoacetate + trimethyloxosulfonium bromide (25596-24-1) → methyl 2-(2-chloro-5-(4-chlorophenoxy)phenyl)oxirane-2-carboxylate

Conditions	Yield
With sodium hydride In dichloromethane for 1h;	37.5%

sodium triazole (41253-21-8) + methyl 2-(2-chloro-4-[4-(pentafluoro-λ6-sulfanyl)phenoxy]phenyl)-2-oxoacetate + trimethyloxosulfonium bromide (25596-24-1) → methyl 2-(2-chloro-4-(4-(pentafluoro-λ6-sulfanyl)phenoxy)phenyl)-2-hydroxy-3-(1H-1,2,4-triazol-1-yl)propionate

Conditions	Yield
In N,N-dimethyl acetamide at 50℃; for 3h;	35.3%

1-(1-chlorocyclopropyl)-4-penten-1-one (1311370-63-4) + trimethyloxosulfonium bromide (25596-24-1) → 2-(3-butenyl)-2-(1-chlorocyclopropyl)oxirane (1311370-64-5)

Conditions	Yield
Stage #1: trimethyloxosulfonium bromide With sodium hydride In dimethyl sulfoxide; mineral oil at 20℃; for 1.5h; Inert atmosphere; Stage #2: 1-(1-chlorocyclopropyl)-4-penten-1-one In dimethyl sulfoxide; mineral oil at 20℃; for 3h; Product distribution / selectivity;	31%

sodium triazole (41253-21-8) + methyl 2-(2-chloro-4-(4-chloro-3-fluorophenoxy)phenyl)-2-oxoacetate + trimethyloxosulfonium bromide (25596-24-1) → methyl 2-(2-chloro-4-(4-chloro-3-fluorophenoxy)phenyl)-2-hydroxy-3-(1H-1,2,4-triazol-1-yl)propanoate

Conditions	Yield
In N,N-dimethyl-formamide at 0 - 50℃; for 3h;	29.3%

sodium triazole (41253-21-8) + methyl 2-(2-chloro-4-(naphthalen-1-yloxy)phenyl)-2-oxoacetate + trimethyloxosulfonium bromide (25596-24-1) → 2-(2-chloro-4-(naphthalen-1-yloxy)phenyl)-2-hydroxy-3-(1H-1,2,4-triazol-1-yl) methyl propionate

Conditions	Yield
In N,N-dimethyl acetamide at 20 - 50℃; for 3.5h;	27.9%

sodium triazole (41253-21-8) + methyl 2-(4-(4-bromo-3-fluorophenoxy)-2-chlorophenyl)-2-oxoacetate + trimethyloxosulfonium bromide (25596-24-1) → methyl 2-[4-(4-bromo-3-fluorophenoxy)-2-chlorophenyl]-2-hydroxy-3-(1H-1,2,4-triazol-1-yl)propanoate

Conditions	Yield
In N,N-dimethyl acetamide at 20 - 50℃; for 2.5h;	27.2%

sodium triazole (41253-21-8) + methyl 2-(2-chloro-4-(4-cyanophenoxy)phenyl)-2-oxoacetate + trimethyloxosulfonium bromide (25596-24-1) → methyl 2-(2-chloro-4-(4-cyanophenoxy)phenyl)-2-hydroxy-3-(1H-1,2,4-triazol-1-yl)propanoate

Conditions	Yield
In N,N-dimethyl-formamide at 20 - 50℃; for 2h;	25.8%

sodium triazole (41253-21-8) + methyl 2-(2-chloro-4-(4-(trifluoromethyl)phenoxy)phenyl)-2-oxoacetate + trimethyloxosulfonium bromide (25596-24-1) → methyl 2-(2-chloro-4-(4-(trifluoromethyl)phenoxy)phenyl)-2-hydroxy-3-(1H-1,2,4-triazole-1-yl)propanoate

Conditions	Yield
In N,N-dimethyl-formamide at 50℃; for 2h;	25.5%

sodium triazole (41253-21-8) + methyl 2-(2-chloro-4-((4-chlorobenzyl)oxy)phenyl)-2-oxoacetate + trimethyloxosulfonium bromide (25596-24-1) → methyl 2-(2-chloro-4-((4-chlorobenzyl)oxy)phenyl)-2-hydroxy-3-(1H-1,2,4-triazol-1-yl)propanoate

Conditions	Yield
In N,N-dimethyl acetamide at 20 - 50℃; for 2.5h;	25.5%

sodium triazole (41253-21-8) + methyl 2-(2-chloro-4-(4-(trifluoromethoxy)phenoxy)phenyl)-2-oxoacetate + trimethyloxosulfonium bromide (25596-24-1) → methyl 2-(2-chloro-4-[4-(trifluoromethoxy)phenoxy]phenyl)-2-hydroxy-3-(1H-1,2,4-triazol-1-yl)propanoate

Conditions	Yield
In N,N-dimethyl-formamide at 50℃; for 2.5h;	25.1%

sodium triazole (41253-21-8) + methyl 2-(2-chloro-4-(3,4-difluorophenoxy)phenyl)-2-oxoacetate + trimethyloxosulfonium bromide (25596-24-1) → methyl 2-(2-chloro-4-(3,4-difluorophenoxy)phenyl)-2-hydroxy-3-(1H-1,2,4-triazol-1-yl)propanoate

Conditions	Yield
In N,N-dimethyl-formamide at -20 - 50℃; for 3h;	24.4%

Upstream product

• 74-83-9 methyl bromide 
• 67-68-5 dimethyl sulfoxide 

Downstream Products

• 126918-35-2 (1R)-1-<(2R)-2-(2,4-difluorophenyl)-2-oxiranyl>ethanol 
• 150802-86-1 (1R)-1-<(2S)-2-(2,4-difluorophenyl)-2-oxiranyl>ethanol 
• 13422-55-4 CH₃Cb₁ 
• 660450-87-3 ethyl 2-[3-{[(tert-butoxycarbonyl)amino]methyl}-4-(4-methylphenyl)-2-propylquinolin-6-yl]cyclopropane-1-carboxylate 
• 125116-23-6 metconazole 
• 125225-28-7 ipconazole 
• 75-18-3 dimethylsulfide 

Relevant articles and documents

Process for the preparation of trimethylsulfoxonium bromide

The present invention is concerned with an improved process for the preparation of trimethylsulfoxonium bromide. The improvement in the process comprises the addition of a scavenger to the reaction mixture of dimethyl sulfoxide and methyl bromide.