Trifluorotoluene
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Names | |||
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Preferred IUPAC name (Trifluoromethyl)benzene | |||
Other names Benzotrifluoride (BTF) α,α,α-Trifluorotoluene CF3Ph PhCF3 | |||
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3D model (JSmol) |
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ChemSpider |
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ECHA InfoCard | 100.002.396 ![]() | ||
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CompTox Dashboard (EPA) |
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InChI
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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 | ||
Refractive index (nD) | 1.41486 (13 °C) | ||
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NFPA 704 (fire diamond) | ![]() 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). ![]() ![]() ![]() Infobox references |
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
- ^ a b Banks, R.E. Organofluorine Chemicals and their Industrial Applications, Ellis Horwood LTD, Chichester, 1979.
- ^ 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
- ^ 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.
- ^ 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.
- ^ 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.
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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 |
- AgPF6
- KAsF6
- LiAsF6
- NaAsF6
- HPF6
- HSbF6
- NH4PF6
- LiSbF6
- KPF6
- KSbF6
- LiPF6
- NaPF6
- NaSbF6
- TlPF6
- Cs2AlF5
- Li3AlF6
- K3AlF6
- Na3AlF6
and pseudohalogenides
- BaSiF6
- BaGeF6
- (NH4)2SiF6
- Na2[SiF6]
- K2[SiF6]
- Li2GeF6
- Li2SiF6
- CBrF3
- CBr2F2
- CBr3F
- CClF3
- CCl2F2
- CCl3F
- CF2O
- CF3I
- CHF3
- CH2F2
- CH3F
- C2Cl3F3
- C2H3F
- C6H5F
- C7H5F3
- C15F33N
- C3H5F
- C6H11F
lanthanide, actinide, ammonium
- VOF3
- CrOF4
- CrF2O2
- NH4F
- (NH4)2ZrF6
- CsXeF7
- Li2SnF6
- Li2TiF6
- Li2ZrF6
- K2TiF6
- Rb2TiF6
- Na2TiF6
- Na2ZrF6
- K2NbF7
- K2TaF7
- K2ZrF6
- UO2F2
- FNO
- FNO2
- FNO3
- KHF2
- NaHF2
- NH4HF2
and iodosyl
- F2OS
- F3OP
- PSF3
- IOF3
- IO3F
- IOF5
- IO2F
- IO2F3