Trifluorotoluene

Trifluorotoluene
Names
Preferred IUPAC name
(Trifluoromethyl)benzene
Other names
Benzotrifluoride (BTF)
α,α,α-Trifluorotoluene
CF3Ph
PhCF3
Identifiers
CAS Number
  • 98-08-8 checkY
3D model (JSmol)
  • Interactive image
ChemSpider
  • 7090
ECHA InfoCard 100.002.396 Edit this at Wikidata
EC Number
  • 202-635-0
PubChem CID
  • 7368
UNII
  • 49R6421K89 checkY
CompTox Dashboard (EPA)
  • DTXSID2024589 Edit this at Wikidata
InChI
  • InChI=1S/C7H5F3/c8-7(9,10)6-4-2-1-3-5-6/h1-5H
    Key: GETTZEONDQJALK-UHFFFAOYSA-N
  • C1=CC=C(C=C1)C(F)(F)F
Properties
Chemical formula
C6H5CF3
Molar mass 146.11 g/mol
Appearance colorless liquid
Odor aromatic
Density 1.19 g/mL at 20 °C
Melting point −29.05 °C (−20.29 °F; 244.10 K)
Boiling point 103.46 °C (218.23 °F; 376.61 K)
Solubility in water
<0.1 g/100 mL at 21 °C
Solubility soluble in ether, benzene, ethanol, acetone
miscible in n-heptane, CCl4
1.41486 (13 °C)
Hazards
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 0: Exposure under fire conditions would offer no hazard beyond that of ordinary combustible material. E.g. sodium chlorideFlammability 3: Liquids and solids that can be ignited under almost all ambient temperature conditions. Flash point between 23 and 38 °C (73 and 100 °F). E.g. gasolineInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
0
3
0
Flash point 12 °C (54 °F; 285 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references
Chemical compound

Trifluorotoluene is an organic compound with the formula of C6H5CF3. This colorless fluorocarbon is used as a specialty solvent in organic synthesis and an intermediate in the production of pesticides and pharmaceuticals.[1]

Synthesis

For small-scale laboratory preparations, trifluorotoluene is synthesized by coupling an aromatic halide and trifluoromethyl iodide in the presence of a copper catalyst:[2]

PhX + CF3I → PhCF3 (where X = I, Br)

Industrial production is done by reacting benzotrichloride with hydrogen fluoride in a pressurized reactor.[3]

PhCCl3 + 3 HF → PhCF3 + 3 HCl

Uses

Trifluorotoluene has a variety of niche uses.

Low toxicity alternative to dichloromethane

According to Ogawa and Curran, trifluorotoluene is similar to dichloromethane in standard acylation, tosylation, and silylation reactions.[4] The dielectric constants for dichloromethane and trifluorotoluene are 9.04 and 9.18, respectively, indicating similar solvating properties. Dipole moments compare less favorably: 1.89 and 2.86 D for dichloromethane and trifluorotoluene, respectively. Replacing dichloromethane is advantageous when conditions require higher boiling solvents, since trifluorotoluene boils at 103 °C it has a higher boiling point than dichloromethane, which has a boiling point of ~40 °C.

As a solvent, trifluorotoluene is useful in mild Lewis-acid catalyzed reactions, such as the Friedel-Crafts preparations. The most common catalyst, aluminium trichloride reacts with trifluorotoluene at room temperature; however, zinc chloride does not.

Synthetic intermediate

A second and perhaps more valuable use of trifluorotoluene is as a synthetic intermediate. A derivative of trifluorotoluene, 3-aminobenzotrifluoride, is the precursor to the herbicide fluometuron.[3] It is synthesized via nitration followed by reduction to meta-H2NC6H4CF3. This aniline is then converted to the urea.

Flumetramide (6-[4-(trifluoromethyl)phenyl]morpholin-3-one), a skeletal muscle relaxant, is also prepared from trifluorotoluene.[1]

Analytics

Trifluorotoluene appears in 19F NMR as a singlet at -63.2 ppm.[5]

References

  1. ^ a b Banks, R.E. Organofluorine Chemicals and their Industrial Applications, Ellis Horwood LTD, Chichester, 1979.
  2. ^ Ogawa, Akiya; Tsuchii, Kaname "α,α,α-Trifluorotoluene" in Encyclopedia of Reagents for Organic Synthesis 2005, John Wiley and Sons. doi:10.1002/047084289X.rn00653
  3. ^ a b Siegemund, Günter "Aromatic Compounds with Fluorinated Side-Chains" in Ullmann’s Encyclopedia of Industrial Chemistry 2005, Wiley-VCH. doi:10.1002/14356007.a11_349.
  4. ^ Ogawa, Akiya; Curran, Dennis P. (1997). "Benzotrifluoride: A Useful Alternative Solvent for Organic Reactions Currently Conducted in Dichloromethane and Related Solvents". Journal of Organic Chemistry. 62 (3): 450–451. doi:10.1021/jo9620324. PMID 11671431.
  5. ^ Denmark, Scott E.; Smith, Russell C. (3 February 2010). "Mechanistic Duality in Palladium-Catalyzed Cross-Coupling Reactions of Aryldimethylsilanolates. Intermediacy of an 8-Si-4 Arylpalladium(II) Silanolate (Supplementary Material, referenced as PhCF3)". Journal of the American Chemical Society. 132 (4): 1243–1245. doi:10.1021/ja907049y. PMC 2812642. PMID 20058920.
  • v
  • t
  • e
HF He
LiF BeF2 BF
BF3
B2F4
CF4
CxFy
NF3
N2F4
OF
OF2
O2F2
O2F
F Ne
NaF MgF2 AlF
AlF3
SiF4 P2F4
PF3
PF5
S2F2
SF2
S2F4
SF4
S2F10
SF6
ClF
ClF3
ClF5
HArF
ArF2
KF CaF2 ScF3 TiF3
TiF4
VF2
VF3
VF4
VF5
CrF2
CrF3
CrF4
CrF5
CrF6
MnF2
MnF3
MnF4
FeF2
FeF3
CoF2
CoF3
NiF2
NiF3
CuF
CuF2
ZnF2 GaF3 GeF4 AsF3
AsF5
SeF4
SeF6
BrF
BrF3
BrF5
KrF2
KrF4
KrF6
RbF SrF2 YF3 ZrF4 NbF4
NbF5
MoF4
MoF5
MoF6
TcF6 RuF3
RuF4
RuF5
RuF6
RhF3
RhF5
RhF6
PdF2
Pd[PdF6]
PdF4
PdF6
AgF
AgF2
AgF3
Ag2F
CdF2 InF3 SnF2
SnF4
SbF3
SbF5
TeF4
TeF6
IF
IF3
IF5
IF7
XeF2
XeF4
XeF6
XeF8
CsF BaF2 * LuF3 HfF4 TaF5 WF4
WF6
ReF6
ReF7
OsF4
OsF5
OsF6
OsF
7

OsF8
IrF3
IrF5
IrF6
PtF2
Pt[PtF6]
PtF4
PtF5
PtF6
AuF
AuF3
Au2F10
AuF5·F2
HgF2
Hg2F2
HgF4
TlF
TlF3
PbF2
PbF4
BiF3
BiF5
PoF4
PoF6
At RnF2
RnF6
Fr RaF2 ** Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og
* LaF3 CeF3
CeF4
PrF3
PrF4
NdF3 PmF3 SmF2
SmF3
EuF2
EuF3
GdF3 TbF3
TbF4
DyF3 HoF3 ErF3 TmF2
TmF3
YbF2
YbF3
** AcF3 ThF4 PaF4
PaF5
UF3
UF4
UF5
UF6
NpF3
NpF4
NpF5
NpF6
PuF3
PuF4
PuF5
PuF6
AmF3
AmF4
AmF6
CmF3 Bk Cf Es Fm Md No
PF6, AsF6, SbF6 compounds
  • AgPF6
  • KAsF6
  • LiAsF6
  • NaAsF6
  • HPF6
  • HSbF6
  • NH4PF6
  • LiSbF6
  • KPF6
  • KSbF6
  • LiPF6
  • NaPF6
  • NaSbF6
  • TlPF6
AlF6 compounds
  • Cs2AlF5
  • Li3AlF6
  • K3AlF6
  • Na3AlF6
chlorides, bromides, iodides
and pseudohalogenidesSiF62-, GeF62- compounds
  • BaSiF6
  • BaGeF6
  • (NH4)2SiF6
  • Na2[SiF6]
  • K2[SiF6]
  • Li2GeF6
  • Li2SiF6
Oxyfluorides
  • BrOF3
  • BrO2F
  • BrO3F
  • LaOF
  • ThOF2
  • VOF
    3
  • TcO
    3
    F
  • WOF
    4
  • YOF
  • ClOF3
  • ClO2F3
Organofluorides
  • CBrF3
  • CBr2F2
  • CBr3F
  • CClF3
  • CCl2F2
  • CCl3F
  • CF2O
  • CF3I
  • CHF3
  • CH2F2
  • CH3F
  • C2Cl3F3
  • C2H3F
  • C6H5F
  • C7H5F3
  • C15F33N
  • C3H5F
  • C6H11F
with transition metal,
lanthanide, actinide, ammonium
  • VOF3
  • CrOF4
  • CrF2O2
  • NH4F
  • (NH4)2ZrF6
  • CsXeF7
  • Li2SnF6
  • Li2TiF6
  • Li2ZrF6
  • K2TiF6
  • Rb2TiF6
  • Na2TiF6
  • Na2ZrF6
  • K2NbF7
  • K2TaF7
  • K2ZrF6
  • UO2F2
nitric acids
bifluorides
  • KHF2
  • NaHF2
  • NH4HF2
thionyl, phosphoryl,
and iodosyl
  • F2OS
  • F3OP
  • PSF3
  • IOF3
  • IO3F
  • IOF5
  • IO2F
  • IO2F3