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
• Article Data: 1

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

General Description

Trimethylsulfoxonium bromide is an organosulfur compound with the molecular formula (CH3)3S+Br-. It is a quaternary ammonium salt, with a sulfur atom at the center of the molecule. This chemical is used as a reagent in organic synthesis, particularly in the preparation of sulfoxides and sulfonium salts. Trimethylsulfoxonium bromide can act as a powerful methylating agent, and also as a source of trimethylsulfonium cation, which can be used for the generation of reactive sulfonium ylides. Overall, it is a versatile compound with various applications in organic chemistry.

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

• 125116-23-6 metconazole 
• 125225-28-7 ipconazole 
• 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 

Relevant articles and documents

-

-