Name | chlorodifluoroacetic anhydride |
Synonyms | Chlorodifluoroacetic anhyride chlorodifluoroacetic anhydride Bis(chlorodifluoroacetic)anhydride 2-chloro-2,2-difluoroacetic anhydride Acetic acid, chlorodifluoro-, anhydride Acetic acid,2-chloro-2,2-difluoro-, 1,1'-anhydride Acetic acid, 2-chloro-2,2-difluoro-, 1,1'-anhydride S-{2-[methoxy(propan-2-yl)amino]-2-oxoethyl} O,O-dimethyl phosphorodithioate |
CAS | 2834-23-3 |
EINECS | 220-603-4 |
InChI | InChI=1/C8H18NO4PS2/c1-7(2)9(11-3)8(10)6-16-14(15,12-4)13-5/h7H,6H2,1-5H3 |
Molecular Formula | C4Cl2F4O3 |
Molar Mass | 242.93 |
Density | 1.395 g/mL at 25 °C (lit.) |
Boling Point | 96-97 °C (lit.) |
Flash Point | None |
Water Solubility | Slightly Soluble in water. (1.4 g/L) (25°C) |
Vapor Presure | 0.000439mmHg at 25°C |
Appearance | clear liquid |
Specific Gravity | 1.395 |
Color | Colorless to Almost colorless |
BRN | 1912832 |
Sensitive | Lachrymatory |
Refractive Index | 1.347 |
Hazard Symbols | C - Corrosive |
Risk Codes | R23/24/25 - Toxic by inhalation, in contact with skin and if swallowed. R34 - Causes burns R21/22 - Harmful in contact with skin and if swallowed. |
Safety Description | S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S36/37/39 - Wear suitable protective clothing, gloves and eye/face protection. S45 - In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.) |
UN IDs | 3265 |
WGK Germany | 3 |
TSCA | T |
Hazard Note | Corrosive/Lachrymatory |
Hazard Class | 8 |
Packing Group | II |
EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
introduction | chlorodifluoroacetic anhydride is a low-carbon chain symmetric anhydride. Acid anhydride has a wide range of applications in the chemical and pharmaceutical fields. There are many reported methods for synthesizing acid anhydride. The reaction of acid chloride and carboxylic acid can be used to prepare acid anhydride, but generally it is necessary to prepare acid chloride first and then react with carboxylic acid. The preparation process of this two-step method is more complicated, so this method is often used to synthesize asymmetric acid anhydride. |
preparation method | a preparation method of high purity chlorodifluoroacetic anhydride with few side reactions, high yield and simple operation is as follows: at a temperature of 20°C, chlorodifluoroacetic acid (1.0mol) and phosphorus pentoxide (35.5g,0.25mmol) are sequentially added to 98% concentrated sulfuric acid (196g,2.0mol) while stirring, after stirring for 0.5h, it was fully mixed, reacted at 100°C for 2h, and the fraction at 93-96°C was collected by vacuum distillation to obtain 59.2g of chlorodifluoroacetic anhydride with 88.5% yield and 98.8% purity (GC). |