120801-75-4

Basic information

• Product Name: Trimethylsilyl 2-(fluorosulfonyl)difluoroacetate
• Synonyms: TRIMETHYLSILYL FLUOROSULFONYLDIFLUOROACETATE;TRIMETHYLSILYL 2,2-DIFLUORO-2-(FLUOROSULFONYL)ACETATE;TRIMETHYLSILYL 2-(FLUOROSULFONYL)DIFLUOROACETATE;TRIMETHYLSILYL 2-(FLUOROSULPHONYL)DIFLUOROACETATE;TRIMETHYLSILYL 2,2-DIFLUORO-2-(FLUOROSUL;Trimethylsilyl 2-(fluorosulphonyl)difluoroacetate 97%;Trimethylsilyl2-(fluorosulphonyl)difluoroacetate97%;TriMethylsilyl Difluoro(fluorosulfonyl)acetate
• CAS NO: 120801-75-4
• Molecular Formula: C₅H₉F₃O₄SSi
• Molecular Weight: 250.27
• Product Categories: C-C Bond Formation;Others;Synthetic Reagents
• Mol File: 120801-75-4.mol
• Article Data: 8

Chemical Properties

• Boiling Point: 156 °C(lit.)
• Flash Point: 80 °F
• Appearance: /
• Density: 1.27 g/mL at 25 °C(lit.)
• Vapor Pressure: 0.000814mmHg at 25°C
• Refractive Index: n20/D 1.367(lit.)
• Solubility: Soluble in ether, toluene, and diglyme.
• Water Solubility: Reacts with water.
• CAS DataBase Reference: Trimethylsilyl 2-(fluorosulfonyl)difluoroacetate(CAS DataBase Reference)
• NIST Chemistry Reference: Trimethylsilyl 2-(fluorosulfonyl)difluoroacetate(120801-75-4)
• EPA Substance Registry System: Trimethylsilyl 2-(fluorosulfonyl)difluoroacetate(120801-75-4)

Safety Data

• Hazard Codes: C,F,Xi
• Statements: 10-34
• Safety Statements: 16-26-27-36/37/39-45
• RIDADR: UN 2920 8/PG 2
• WGK Germany: 2
• HazardClass: 8
• PackingGroup: II
• Hazardous Substances Data: 120801-75-4(Hazardous Substances Data)

Usage

Physical properties

73–74 °C at 35mm Hg.

Uses

Different sources of media describe the Uses of 120801-75-4 differently. You can refer to the following data:
1. Trimethylsilyl Fluorosulfonyldifluoroacetate is a reagent used in Synthesis of gem-Difluorocyclopropanes, Synthesis of gem-Difluorocyclopropenes, etc.
2. Fluoroalkylation agentReactant for:Preparation of difluorocyclopropenesPreparation of difluorocarbene reagents
3. Fluoroalkylation agent. Reactant for Preparation of difluorocyclopropenes and Preparation of difluorocarbene reagents.

Preparation

Prepared by treatment of FO2SCF2CO2H with (CH3)3SiCl.

InChI:InChI=1/C7H2Cl2FNO3/c8-4-2-5(10)6(11(13)14)1-3(4)7(9)12/h1-2H

Synthetic route

Hexamethyldisiloxane (107-46-0) + fluorosulfonyldifluoroacetyl fluoride (677-67-8) → trimethylsilyl fluoride (420-56-4) + 2,2-difluoro-2-(fluorosulfonyl)acetic acid (1717-59-5) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4)

Conditions	Yield
Stage #1: Hexamethyldisiloxane; fluorosulfonyldifluoroacetyl fluoride at 0 - 100.6℃; under 4350.44 - 5925.59 Torr; for 18h; Stage #2: With chloro-trimethyl-silane at 20 - 107.8℃; Product distribution / selectivity; Heating / reflux;	A n/a B n/a C 85%

Hexamethyldisiloxane (107-46-0) + fluorosulfonyldifluoroacetyl fluoride (677-67-8) → trimethylsilyl fluoride (420-56-4) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4)

Conditions	Yield
With chloro-trimethyl-silane at 105℃; under 4200.42 Torr; for 6h;	A n/a B 84%

chloro-trimethyl-silane (75-77-4) + 2,2-difluoro-2-(fluorosulfonyl)acetic acid (1717-59-5) → trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4)

Conditions	Yield
at 0 - 20℃; for 26h; Inert atmosphere;	83%
at 20℃;	78%
at 0℃; Esterification;	78%
for 12h; Heating;
at 0 - 65℃; for 19h; Inert atmosphere;

trimethylsilyl iodide (16029-98-4) + (fluorosulfonyl)difluoroacetic acid silver salt → trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4)

Conditions	Yield
for 24h; -196 deg C upto room temp.;	29%

N-(cyclohexylthiocarbonyl)aniline (53300-46-2) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → S-difluoromethyl N-phenylcyclohexanecarbothioimidate

Conditions	Yield
With N,N,N',N'-tetramethyl-1,8-diaminonaphthalene In toluene at 80℃; for 0.166667h; Temperature; Solvent; Optical yield = 58 %de;	100%

4-Methoxyphenylthiocarbamidsaeure-O-isopropylester (22007-40-5) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → S-(difluoromethyl) O-isopropyl N-(p-methoxyphenyl)carbonimidothioate

Conditions	Yield
With N,N,N',N'-tetramethyl-1,8-diaminonaphthalene In toluene at 50℃; for 0.166667h;	97%

2-chloro-3-quinoline carboxaldehyde (73568-25-9) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → 2-chloro-3-(2,2-difluorovinyl)quinoline

Conditions	Yield
Stage #1: 2-chloro-3-quinoline carboxaldehyde With sodium fluoride; triphenylphosphine In ethyl acetate at 90℃; for 0.0166667h; Wittig Olefination; Schlenk technique; Inert atmosphere; Stage #2: trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate In ethyl acetate at 90℃; for 1h; Schlenk technique; Inert atmosphere;	96%

2-bromo-3-[tert-butyl(dimethyl)silyloxy]-1-phenylbuta-1,3-diene + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → 1-(1-bromo-2-phenylethenyl)-1-[tert-butyl(dimethyl)silyloxy]-2,2-difluorocyclopropan

Conditions	Yield
With N,N,N',N'-tetramethyl-1,8-diaminonaphthalene In toluene at 60℃; for 0.25h;	96%
With 1,1,1,3,3,3-hexafluoro-2,2-di(p-tolyl)propane; N,N,N',N'-tetramethyl-1,8-diaminonaphthalene In para-xylene at 60℃; for 0.25h; regioselective reaction;

trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) + 3-(4-methoxyphenyl)-1-phenylprop-2-yn-1-one (20442-66-4) → [3,3-difluoro-2-(4-methoxy-phenyl)-cycloprop-1-enyl]-phenyl-methanone (882182-82-3)

Conditions	Yield
With sodium fluoride In diethylene glycol dimethyl ether at 120℃; for 3h;	95%

cinnamyl benzoate (50555-04-9) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → trans-2,2-difluoro-3-phenylcyclopropylmethyl benzoate

Conditions	Yield
With sodium fluoride In various solvent(s) at 120℃;	94%

phenyl o-phenylbenzenedithiocarboxylate + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → 1-(biphenyl-2-yl)-2,2-difluoro-1-(phenylsulfanyl)ethene

Conditions	Yield
With N,N,N',N'-tetramethyl-1,8-diaminonaphthalene In toluene for 0.5h; Barton-Kellog Olefination; Schlenk technique; Reflux;	94%

phenylpropynoic acid methyl ester (4891-38-7) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → methyl 3,3-difluoro-2-phenylcycloprop-1-ene-1-carboxylate

Conditions	Yield
With sodium fluoride In diethylene glycol dimethyl ether at 120℃;	94%

2-formylbenzo[b]furan (4265-16-1) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → 2-(2,2-difluorovinyl)benzo[b]furan (1449521-09-8)

Conditions	Yield
Stage #1: 2-formylbenzo[b]furan With sodium fluoride; triphenylphosphine In ethyl acetate at 90℃; for 0.0166667h; Wittig Olefination; Schlenk technique; Inert atmosphere; Stage #2: trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate In ethyl acetate at 90℃; for 1h; Schlenk technique; Inert atmosphere;	93%

methyl N-phenylthiocarbamate (13509-41-6) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → S-(difluoromethyl) O-methyl N-phenylcarbonimidothioate

Conditions	Yield
With N,N,N',N'-tetramethyl-1,8-diaminonaphthalene In toluene at 50℃; for 0.166667h;	93%

1-pentyl-1-hexenyl acetate (139225-17-5) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → 5,6-difluoromethylene-6-acetoxyundecane (74667-07-5)

Conditions	Yield
With sodium fluoride In various solvent(s) at 120℃;	92%

3,6-dimethyl-5-nitropyridin-2-ol (57179-69-8) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → 2-(difluoromethoxy)-3,6-dimethyl-5-nitropyridine (1188407-31-9)

Conditions	Yield
Stage #1: 3,6-dimethyl-5-nitropyridin-2-ol With sodium hydride In acetonitrile at 20℃; for 0.5h; Stage #2: trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate With cesium fluoride In acetonitrile at 23 - 30℃;	92%
With sodium hydride; cesium fluoride In acetonitrile at 23 - 30℃; for 1.66667h; Inert atmosphere;	92%

3,6-dimethyl-5-nitropyridin-2-one (57179-69-8) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → 2-(difluoromethoxy)-3,6-dimethyl-5-nitropyridine (1188407-31-9)

Conditions	Yield
With sodium hydride; cesium fluoride In acetonitrile; mineral oil at 20℃; for 1.16667h;	92%

3-[tert-butyl(dimethyl)silyloxy]-2-methyl-1-phenylbuta-1,3-diene + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → 1-[tert-butyl(dimethyl)silyloxy]-2,2-difluoro-1-(1-methyl-2-phenylethenyl)cyclopropane

Conditions	Yield
With N,N,N',N'-tetramethyl-1,8-diaminonaphthalene In toluene at 60℃; for 0.25h;	92%
With 1,1,1,3,3,3-hexafluoro-2,2-di(p-tolyl)propane; N,N,N',N'-tetramethyl-1,8-diaminonaphthalene In para-xylene at 60℃; for 0.25h; regioselective reaction;

phenyl m-chlorobenzenedithiocarboxylate (90982-74-4) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → 1-m-chlorophenyl-2,2-difluoro-1-(phenylsulfanyl)ethene

Conditions	Yield
With N,N,N',N'-tetramethyl-1,8-diaminonaphthalene In toluene for 0.5h; Barton-Kellog Olefination; Schlenk technique; Reflux;	92%

6-methyl-5-nitropyridin-2-ol (28489-45-4) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → 6-(difluoromethoxy)-2-methyl-3-nitropyridine (1224432-76-1)

Conditions	Yield
With sodium hydride; cesium fluoride In acetonitrile	91%

C17H14O (1429215-66-6) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → phenyl 2,2-difluoro-3-(3,5-dimethylphenyl)cyclopropenyl ketone (1429215-44-0)

Conditions	Yield
With sodium fluoride In diethylene glycol dimethyl ether at 120℃; for 1h; Inert atmosphere;	91%

m-bromobenzoic aldehyde (3132-99-8) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → 1-bromo-3-(2,2-difluorovinyl)benzene (84750-92-5)

Conditions	Yield
Stage #1: m-bromobenzoic aldehyde With sodium fluoride; triphenylphosphine In ethyl acetate at 90℃; for 0.0166667h; Wittig Olefination; Schlenk technique; Inert atmosphere; Stage #2: trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate In ethyl acetate at 90℃; for 1h; Schlenk technique; Inert atmosphere;	91%

1-propenylbenzene (873-66-5) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → trans-1,1-difluoro-2-methyl-3-phenylcyclopropane

Conditions	Yield
With sodium fluoride In various solvent(s) at 105℃;	90%

trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) + 1-(4-(tert-butyl)phenyl)-3-phenylprop-2-yn-1-one (671796-41-1) → 4-t-butylphenyl 2,2-difluoro-3-phenylcyclopropenyl ketone (882182-78-7)

Conditions	Yield
With sodium fluoride In diethylene glycol dimethyl ether at 120℃; for 1h; Inert atmosphere;	90%
With sodium fluoride In diethylene glycol dimethyl ether at 120℃; for 3h;	85%

trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) + 1-phenyl-3-(4-methylphenyl)prop-2-yn-1-one (14939-05-0) → phenyl 2,2-difluoro-3-(4-methylphenyl)cyclopropenyl ketone (882182-83-4)

Conditions	Yield
With sodium fluoride In diethylene glycol dimethyl ether at 120℃; for 3h;	90%
With sodium fluoride In diethylene glycol dimethyl ether at 120℃; for 1h; Inert atmosphere;	87%

1,2,3,4-tetrahydronaphthalen-2-one (530-93-8) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → 2-(difluoromethoxy)naphthalene (712-79-8)

Conditions	Yield
Stage #1: 1,2,3,4-tetrahydronaphthalen-2-one; trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate With sodium carbonate; 1,3-bis(mesityl)imidazolium chloride In toluene at 100℃; for 1h; Stage #2: With 2,3-dicyano-5,6-dichloro-p-benzoquinone In toluene at 100℃;	90%

vinyl benzoate (583-04-0) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → [2,2-difluorocyclopropyl]methylbenzoate

Conditions	Yield
With sodium fluoride at 105℃;	89%

3-butenyl benzoate (18203-32-2) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → 2-(2,2-difluorocyclopropyl)ethyl benzoate (117388-09-7)

Conditions	Yield
With sodium fluoride at 105℃;	89%
With sodium fluoride at 110℃; for 2h; Inert atmosphere;	51%
With sodium fluoride In neat (no solvent) at 110℃; for 2h;	51%
With sodium fluoride at 110℃; for 12h;	50%
With sodium fluoride at 125℃; for 12h; Cycloaddition;

1,3-diphenyl-2-propynone (7338-94-5) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → phenyl 2,2-difluoro-3-phenylcyclopropenyl ketone (882182-77-6)

Conditions	Yield
With sodium fluoride In diethylene glycol dimethyl ether at 120℃; for 3h;	89%
With sodium fluoride In diethylene glycol dimethyl ether at 120℃; for 1h; Inert atmosphere;	85%

1-phenyl-3-(3-methylphenyl)prop-2-yn-1-one (14674-99-8) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → phenyl 2,2-difluoro-3-(3-methylphenyl)cyclopropenyl ketone (1429215-43-9)

Conditions	Yield
With sodium fluoride In diethylene glycol dimethyl ether at 120℃; for 1h; Inert atmosphere;	89%

6-(2-chloropyrimidin-4-yl)-1-isopropylimidazo[4,5-c]pyridin-4-ol + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → C14H12ClF2N5O

Conditions	Yield
With sodium hydride; cesium fluoride In acetonitrile; mineral oil at 0℃; for 1h;	89%

trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) + 3-(4-bromophenyl)-1-phenylprop-2-yn-1-one (39833-48-2) → phenyl 2,2-difluoro-3-(4-bromophenyl)cyclopropenyl ketone (882182-84-5)

Conditions	Yield
With sodium fluoride In diethylene glycol dimethyl ether at 120℃; for 3h;	88%
With sodium fluoride In diethylene glycol dimethyl ether at 120℃; for 1h; Inert atmosphere;	85%

1-<<2-cyclohexylideneethenyl>sulfonyl>-4-methylbenzene (91873-75-5) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → 1,1-difluoro-2-[(tolyl-4-sulfonyl)methylidene]spiro[2.5]octane (926033-49-0)

Conditions	Yield
With sodium fluoride In xylene for 3.16667h; Heating;	88%

C23H26O (1429215-67-7) + trimethylsilyl-2,2-difluoro-2-(fluorosulphonyl)acetate (120801-75-4) → phenyl 2,2-difluoro-3-(3,5-di-t-butylphenyl)cyclopropenyl ketone (1429215-45-1)

Conditions	Yield
With sodium fluoride In diethylene glycol dimethyl ether at 120℃; for 1h; Inert atmosphere;	88%

Upstream product

• 75-77-4 chloro-trimethyl-silane 
• 1717-59-5 2,2-difluoro-2-(fluorosulfonyl)acetic acid 
• 107-46-0 Hexamethyldisiloxane 
• 677-67-8 fluorosulfonyldifluoroacetyl fluoride 
• 16029-98-4 trimethylsilyl iodide 

Downstream Products

• 509072-58-6 (2,2-difluorocyclopropyl)methyl p-nitrobenzoate 
• 491593-80-7 1-bromo-4-(3,3-difluoro-2-iodo-cycloprop-1-enyl)-benzene 
• 491593-74-9 1-(3,3-difluoro-2-iodo-cycloprop-1-enyl)-4-methyl-benzene 
• 491593-75-0 1-chloro-4-(3,3-difluoro-2-iodo-cycloprop-1-enyl)-benzene 
• 562812-20-8 2-(2,2-difluoro-3-p-tolyl-cyclopropyl)-[1,3]dioxolane 
• 562812-21-9 2-[2,2-difluoro-3-(4-trifluoromethyl-phenyl)-cyclopropyl]-[1,3]dioxolane 
• 562812-25-3 2-(2,2-difluoro-3-p-tolyl-cyclopropyl)-2-methyl-[1,3]dioxolane 
• 562812-23-1 2-[3-(4-chloro-phenyl)-2,2-difluoro-cyclopropyl]-2-methyl-[1,3]dioxolane 
• 562812-24-2 2-[2,2-difluoro-3-(4-methoxy-phenyl)-cyclopropyl]-2-methyl-[1,3]dioxolane 
• 562812-30-0 2-[3-(4-chloro-phenyl)-2,2-difluoro-cyclopropyl]-2-phenyl-[1,3]dioxolane 
• 562812-28-6 2-(2,2-difluoro-3-p-tolyl-cyclopropyl)-2-phenyl-[1,3]dioxolane 
• 562812-26-4 2-[2,2-difluoro-3-(4-trifluoromethyl-phenyl)-cyclopropyl]-2-methyl-[1,3]dioxolane 
• 562812-31-1 2-[2,2-difluoro-3-(4-trifluoromethyl-phenyl)-cyclopropyl]-2-phenyl-[1,3]dioxolane 
• 133744-89-5 n-butyl 2,2-difluorocyclopropyl ether 

Relevant articles and documents

SILVER (FLUOROSULFONYL)DIFLUOROACETATE - A NEW ROUTE TO FLUOROSULFONYL ESTERS

New fluorinated esters of the type FSO2CF2C(O)OR and (FSO2CF2C(O)O)2R', (R = CH3, CH3CH2CH2, (CH3)3Si, BrCH2CH2, CH3CH2OC(O)CH2, CH2=CHCH2; R' = CH2, CH2CH2, have been prepared and characterized via the reaction of silver difluoro(fluorosulfonyl)acetate with alkylbromides, alkyliodides, and trimethylsilyl iodide.All new compounds have been characterized by their respective IR/MS/NMR spectra.

Preparation method of trimethylsilyl 2 - (fluorosulfonyl) difluoroacetate

The invention relates to the technical field of organic synthesis, and provides a preparation method of trimethylsilyl 2 - (fluorosulfonyl) difluoro acetate, which comprises the following steps: S1, adding pyridine in a dry connected three-port flask connected with a constant pressure dropping funnel, nitrogen protection and a tail gas absorption device. S2, 2 - fluorosulfonyl difluoroacetic acid, triethylamine, and control temperature were added. S3, trimethylchlorosilane was added dropwise to control the temperature. S4, after the dropwise addition, heating to reflux, heat preservation reaction. S5. The methanol solution was added to remove the lower layer and distilled to give the product. Through the technical scheme, the problem of low yield of a preparation method in the prior art is solved.

Trimethylsilyl fluorosulfonyldifluoroacetate (TFDA): A new, highly efficient difluorocarbene reagent

TFDA is readily prepared from the reaction of fluorosulfonyldifluoroacetic acid with trimethylsilyl chloride, and it is a very effective and efficient source of difluorocarbene for use in addition reactions to alkenes of a broad scope of reactivities. Acid-sensitive substrates may require an additional purification step involving treatment of the distilled TFDA with sufficient Et3N to remove the acid impurity. Other trialkylsilyl fluorosulfonyldifluoroacetates can also be prepared, and they have been found to have reactivities similar to TFDA. The triethyl derivative, TEFDA is more convenient to prepare in a pure state and has similar reactivity to TFDA. Thus, it may prove to be a superior reagent.