Trifluoroacetic acid Trifluoroacetic acid

Structural formula

• Numbering system
• Physical property data
• Toxicological data
• Ecological data
• Molecular structure data
• Computing chemical data
• More
  • Properties and Stability
  • Storage method
  • Synthesis method
  • Purpose

Numbering system

CAS number:76-05-1

MDL number:MFCD00004169

EINECS number:200-929-3

RTECS number:AJ9625000

BRN number:742035

PubChem number:24900380

Physical property data

1. Characteristics: Colorless, transparent, hygroscopic fuming liquid with a strong pungent odor. ^[11]

2. Melting point (℃): -15.2^[12]

3. Boiling point (℃): 72.4~74^[13]

4. Relative density (water = 1): 1.54^[14]

5. Relative vapor density (air = 1): 3.9^[15]

6. Saturated vapor pressure (kPa): 14.23 (25℃)^[16]

7. Critical pressure (MPa): 3.26^[17]

8. Octanol/water partition coefficient: 0.5^[18]

9. Solubility: Easily soluble in water, ethanol, ether, acetone, and benzene. ^[19]

10. Viscosity (mPa·s, 20ºC): 0.926

11. Relative density (25℃, 4℃): 1.486

12. Relative density (20℃, 4℃): 1.5351⁰

13. Solubility parameter (J·cm^-3)^0.5: 21.621

14. van der Waals area (cm²·mol^-1): 6.510 ×10⁹

15. van der Waals volume (cm³·mol^-1): 41.070

16. The gas phase standard claims heat (enthalpy) (kJ·mol^-1): -1031.4

17. The liquid phase standard claims heat (enthalpy) (kJ· mol^-1): -1069.9

18. Liquid phase standard hot melt (J·mol^-1·K^-1): 170.2

Toxicological data

1. Acute toxicity: Rat oral LD50: 500mg/kg; rat inhalation LC50: 10mg/m³; mouse inhalation LC50: 13500mg/m³; Mouse intraperitoneal LDLo: 150mg/kg; Mouse intravenous LD50: 1200mg/kg;

2. It is moderately toxic. It has an irritating effect on the skin, eyes and mucous membranes. Its irritation is stronger than trichloroacetic acid, and its penetration into tissues is more obvious. Causes severe pain and burns on contact with skin. When the skin of guinea pigs or rats comes into contact with a trifluoroacetic acid solution of 20% or higher concentration, it causes obvious coagulation necrosis or complete tissue dissolution. The maximum allowable concentration in the workplace is 0.025~0.05mg/L.

3. Acute toxicity ^[20]

LD50: 200mg/kg (rat oral)

LC50: 1000mg/m³ (rat inhalation)

Ecological data

Slightly hazardous to water, avoid contact of undiluted or large quantities of product with groundwater, waterways or sewage systems. Harmful to fish.

Molecular structure data

The � group is a group with good lipophilicity and strong electronegativity. It plays a special role in biologically active molecules. Trifluoromethyl group (Formula 2, Formula 3) ^[6,7] can be introduced into some compound molecules using trifluoroacetic acid.

Carboxylate ester SynthesisTrifluoroacetic anhydride reacts with hydrogen peroxide to generate peroxytrifluoroacetic acid, which can be used to cause the Baeyer-Villiger oxidation reaction of some ketones to generate the corresponding carboxylic acid ester (Formula 4)^[8] .

Used for deprotection ReagentsIn organic reactions, in order to selectively carry out a certain reaction while retaining other more active chemical groups (such as amino groups, hydroxyl groups, etc.), it is often necessary to use some protective groups to protect them. Trifluoroacetic acid can easily remove the protective groups of amino and hydroxyl groups ^[5], for example, N-benzyloxycarbonyl, N -Methoxymethyl (formula 5), ​​N-tert-butoxycarbonyl (formula 6)^[9], O-tert-butoxy Carbonyl (formula 7)^[10], N-benzyloxymethyl, etc.

4. Used as test reagents, Solvents, catalysts and used in organic synthesis. ^[27]