Basic information Fluorinating reagents Uses Preparation Reactions Precautions Safety Supplier Related
ChemicalBook >  Product Catalog >  Organic Chemistry >  Amides >  Acyclic polyamines and their derivatives >  Diethylaminosulfur trifluoride

Diethylaminosulfur trifluoride

Basic information Fluorinating reagents Uses Preparation Reactions Precautions Safety Supplier Related

Diethylaminosulfur trifluoride Basic information

Product Name:
Diethylaminosulfur trifluoride
Synonyms:
  • (beta-4)-sulfu
  • (diethylamino)trifluorosulfur
  • (Diethylethan-aminato)trifluorosulfur
  • (N,N-diethylamino)sulfurtrifluoride
  • (N-ethylethanaminato)-trifluorosulfur
  • Diethylamino-schwefeltrifluorid
  • Diethylaminotrifluorosulfur
  • ethanamine,N-ethyl-,sulfurcomplex
CAS:
38078-09-0
MF:
C4H10F3NS
MW:
161.19
EINECS:
253-771-2
Product Categories:
  • (DAST
  • Inorganic Fluorides
  • Biochemistry
  • Fluorinating Reagents
  • Fluorinating Reagents & Building Blocks for Fluorinated Biochemical Compounds
  • Fluorination
  • Halogenation
  • Nucleophilic Fluorinating Reagents
  • Reagents for Oligosaccharide Synthesis
  • Synthetic Organic Chemistry
Mol File:
38078-09-0.mol
More
Less

Diethylaminosulfur trifluoride Chemical Properties

Boiling point:
30-32 °C3 mm Hg(lit.)
Density 
1.22 g/mL at 25 °C(lit.)
refractive index 
1.41-1.416
Flash point:
75 °F
storage temp. 
2-8°C
pka
-4.87±0.70(Predicted)
form 
liquid
Specific Gravity
1.220
Water Solubility 
decomposes
Sensitive 
Moisture Sensitive
Merck 
14,3113
BRN 
1849066
InChIKey
CSJLBAMHHLJAAS-UHFFFAOYSA-N
CAS DataBase Reference
38078-09-0(CAS DataBase Reference)
NIST Chemistry Reference
Diethylaminosulfur trifluoride(38078-09-0)
More
Less

Safety Information

Hazard Codes 
C,T,F
Risk Statements 
10-14-20/21/22-34-5-35-40
Safety Statements 
16-26-36/37/39-45
RIDADR 
UN 2920 8/PG 1
WGK Germany 
3
3-10-21
Hazard Note 
Corrosive/Keep Cold
HazardClass 
8
PackingGroup 
I
HS Code 
29309070

MSDS

  • Language:English Provider:DAST
  • Language:English Provider:ACROS
  • Language:English Provider:SigmaAldrich
  • Language:English Provider:ALFA
More
Less

Diethylaminosulfur trifluoride Usage And Synthesis

Fluorinating reagents

N,N-Diethylaminosulfur trifluoride (DAST) is the most widely used fluorinating reagent in this class. It has a similar reactivity to sulfur tetrafluoride, but has the advantage that it can be used in glass vessels at atmospheric pressure. Deoxofluorination reactions with N,N-diethylaminosulfur trifluoride are usually run neat or in anhydrous aprotic solvents, most frequently halogenated solvents, at temperatures of 0- 80 °C. Typically, a stoichiometric amount of the reagent is used for aldehydes and a small excess is used for ketones.

Diethylaminosulfur trifluoride is the most widely used member of this family of reagents, is a pale yellow liquid that reacts violently with water. DAST is readily obtained from commercial sources (e.g. Aldrich or Lancaster) and can also be prepared by the reaction of N,N-di-ethylaminotrimethylsilane with sulfur tetrafluoride, followed by distillation of the crude product under reduced pressure. DAST is known to be thermally unstable, undergoing either explosion or detonation when heated to > 9°ºC.

Uses

Diethylaminosulfur trifluoride (DAST) is used as a precursor to prepare 2,6-dimethoxybenzoyl fluoride and 2-thiazolines. It is a useful fluorinating agent used for a variety of compounds including alcohols, thioethers, alkenols and cyanohydrins. It also serves as a catalyst for Friedel-Crafts allylation reaction using tertiary cyclopropyl silyl ethers and in the rearrangement of homoallylic alcohols to unsaturated aldehydes. It plays an important role for gem difluorination of ketopipecolinic acids.

Preparation

This preparation of diethylaminosulfur trifluoride is an adaptation of a procedure first described by von Halasz and Glemser.The same procedure can also be used to prepare other dialkylaminosulfur trifluorides by the substitution of the diethylaminotrimethylsilane with other dialkylaminotrimethylsilanes.

A solution of 96 g (0.66 mole) of diethylaminotrimethylsilane in 100 ml trichlorofluoromethane was added dropwise to a solution of 40 ml (measured at -78°, 0.72 mole) of sulfur tetrafluoride in 200 ml of trichlorofluoromethane at -65° to -60°. The reaction mixture was warmed to room temperature and then distilled to give 88.86 g (84% yield) of diethylaminosulfur trifluoride as a pale yellow liquid, bp 46°-47° (10 mm).

Reactions

Diethylaminosulfur trifluoride (DAST) has proven itself to be an extremely popular reagent for nucleophilic fluorination, due to its ease of handling and versatility. It has regularly been employed in a myriad selective fluorinations of alcohols, alkenols, carbohydrates, ketones, sulfides, epoxides, thioethers, and cyanohydrins. In addition some novel organic cyclizations are possible when DAST is employed as a reagent.
Fluorodeoxygenation was achieved using DAST in a preparatively simple synthesis of 5,5-difluoropipecolic acid from glutamic acid.

1,2,2-Trifluorostyrenes can be synthesized using a sequential reaction on the parent a-(trifluoromethyl)phenylethanol with DAST, followed by dehydrohalogenation with lithium bis(trimethylsilyl)amide (LHMDS). This method achieves the trifluorostyrene without requirement of palladium coupling.

DAST was recently used to obtain fluorinated analogues of 3,6-dibromocarbazole piperazine derivatives of 2-propanol (Scheme 7). A series of these analogues are described as the first small and potent modulators of the cytochrome c release triggered by Bid-induced Bax activation in a mitochondrial assay.

Precautions

diethylaminosulfur trifluoride (DAST) reacts violently with water, it is volatile, and is reported to be explosive when heated owing to its calorimetry profile and its rapid dismutation to SF4 and (Et2N)2SF2. Furthermore, its decomposition products are themselves highly reactive and will etch laboratory glassware. Accordingly, DAST must be used with extreme caution, and samples are recommended not to be heated above 90 °C.

Chemical Properties

Pale yellow liquid

Uses

Diethylaminosulfur Trifluoride is a very useful fluorinating agent in chemical synthesis. Diethylaminosulfur Trifluoride is also used as a reagent in the preparation of 2-thiazolines from (1,2)-thioam ido-alcohols.

Uses

Nucleophilic fluorinating reagent.

Uses

Diethylaminosulfur trifluoride (DAST) is used as a precursor to prepare 2,6-dimethoxybenzoyl fluoride and 2-thiazolines. It is a useful fluorinating agent used for a variety of compounds including alcohols, thioethers, alkenols and cyanohydrins. It also serves as a catalyst for Friedel-Crafts allylation reaction using tertiary cyclopropyl silyl ethers and in the rearrangement of homoallylic alcohols to unsaturated aldehydes. It plays an important role for gem difluorination of ketopipecolinic acids.

Diethylaminosulfur trifluorideSupplier

BTC Pharmaceutical CO. Ltd Gold
Tel
;
Email
sales3@btcpharm.com;sales12@btcpharm.com
Adamas Reagent, Ltd. Gold
Tel
400-600-9262
Email
bxy@titansci.com
Haimen Ruiyi Medical Tech Co., LTD Gold
Tel
021-54718086-
Email
sales5@ruiyitech.com
Shanghai Yichang Chemical Co., Ltd. Gold
Tel
021-56145923-
Email
sales@yichangchemical.com
Shanghai Chuen Pharmaceutical Technology Co., Ltd. Gold
Tel
Email
3237528851@qq.com