3,4-Difluorophenylacetic acid (658-93-5) is called for Benzeneacetic acid, 3,4-difluoro- ; Rarechem AL BO 0250 ; 2-Flurobenzyl alcohol ; 3,4-Difluorophenylacetic acid 98% ; 3,4-Difluorobenzeneacetic acid ; JRD-0217 ; EINECS 211-527-2 ; BBV-213142 ; TL8004675  ,and so on. 3,4-Difluorophenylacetic acid (658-93-5) is usually like beige crystalline needle.

IUPAC Name: 2-(3,4-Difluorophenyl)acetic acid
CAS: 658-93-5
Molecular Formula: C₈H₆F₂O₂
Molecular Weight: 172.13
Molecular structure:
EINECS: 211-527-2
Melting point:  46-50 °C(lit.)
BRN:  2577768 
ACD/LogD (pH 5.5): 0.07 
ACD/LogD (pH 7.4): -1.68 
ACD/BCF (pH 5.5): 1 
ACD/BCF (pH 7.4): 1 
ACD/KOC (pH 5.5): 5.64 
ACD/KOC (pH 7.4): 1 
H bond acceptors: 2 
H bond donors: 1 
Freely Rotating Bonds: 2 
Index of Refraction: 1.508 
Molar Refractivity: 37.35 cm³ 
Molar Volume: 125.2 cm³ 
Polarizability: 14.8 10^-24cm³ 
Surface Tension: 42.4 dyne/cm 
Density: 1.373 g/cm³ 
Flash Point: 113.3 °C 
Enthalpy of Vaporization: 52.99 kJ/mol 
Boiling Point: 263.8 °C at 760 mmHg 
Vapour Pressure: 0.00508 mmHg at 25°C

 3,4-Difluorophenylacetic acid (658-93-5) is commonly used as pharmaceutical intermediate,pesticide intermediate,and liquid crystal material intermediate.

Hazard Codes:  Xi
Risk Statements:  36/37/38 (36/37/38:  Irritating to eyes, respiratory system and skin)
Safety Statements:  26-36-37/39 (26:  In case of contact with eyes, rinse immediately with plenty of water and seek medical advice 36:  Wear suitable protective clothing 37/39:  Wear suitable gloves and eye/face protection)
WGK Germany:  3
Hazard Note:  Irritant

Removal in wastewater treatment of 3,4-Difluorophenylacetic acid (658-93-5) can be stated as follows:
Total removal:2.12 percent
Total biodegradation:0.09 percent
Total sludge adsorption:2.02 percent
Total to Air:0.00 percent
(using 10000 hr Bio P,A,S)