Name | 2,4-Difluorotoluene |
Synonyms | Difluorotoluene 2,4-Difluorotolune 2,4-DIFLUOROTOLUNE 2,4-Difluorotoluene 2,4-DIFLUOROTOLUENE 2,4-DIFLUOROTOLUINE 2.4-Difluoro methyl benzene 1-Methyl-2,4-difluorobenzene 2,4-DIFLUORO-1-METHYL-BENZENE Benzene, 2,4-difluoro-1-methyl- |
CAS | 452-76-6 |
EINECS | 207-211-9 |
InChI | InChI=1/C7H8FN/c1-5-2-3-6(9)4-7(5)8/h2-4H,9H2,1H3 |
Molecular Formula | C7H6F2 |
Molar Mass | 128.12 |
Density | 1.12 g/mL at 25 °C (lit.) |
Melting Point | -35 °C |
Boling Point | 113-117 °C (lit.) |
Flash Point | 59°F |
Vapor Presure | 0.272mmHg at 25°C |
Appearance | Liquid |
Specific Gravity | 1.120 |
Color | Clear colorless |
BRN | 1931681 |
Storage Condition | Sealed in dry,2-8°C |
Refractive Index | n20/D 1.449(lit.) |
Physical and Chemical Properties | Boiling Point: 114 - 116 density: 1.15 flash point: 13 |
Risk Codes | 11 - Highly Flammable |
Safety Description | S16 - Keep away from sources of ignition. S29 - Do not empty into drains. S33 - Take precautionary measures against static discharges. |
UN IDs | UN 1993 3/PG 2 |
WGK Germany | 3 |
HS Code | 29039990 |
Hazard Note | Flammable |
Hazard Class | 3 |
Packing Group | II |
NIST chemical information | Information provided by: webbook.nist.gov (external link) |
Application | 2,4-difluorotoluene is an organic intermediate that can be prepared from 2,4-diaminotoluene through diazotization reaction. There are reports that it can be used to prepare 2, 4-difluorobenzaldehyde. |
preparation | in a 250ml three-neck bottle, 2, 4-diaminotoluene (6.1g,0.05mol) is added, concentrated hydrochloric acid (36ml) is added, 40% fluoroboric acid (32ml) is added under ice salt bath cooling and stirring, and sodium nitrite (7.6g,0.11mol) solution dissolved in water (12ml). After adding, stir for 1h, filter, and wash the solid with ice water (20ml × 2), anhydrous ethanol and anhydrous ether (15ml × 2 each) respectively. Put into a calcium chloride dryer and dry for 2 hours. Add the diazonium salt (10g) obtained above into a 150ml round bottom flask, carefully heat with an alcohol lamp, and carry out thermal decomposition until a large amount of smoke is generated in the flask, and always maintain above this temperature until no smoke is generated, and the overflow is cooled by a straight condenser tube and a multi-stage cold trap, and the receiving tube is inserted into a conical flask containing ether. After the reaction, it was extracted with ether, combined with ether solution, added anhydrous calcium chloride for drying, and fractionated to obtain 2,4-difluorotoluene (5.3g, yield 82.8%),bp113~117 ℃ (literature: bp112 ℃/99.06kPa, yield 57%). |
uses | intermediates in medicine, pesticides and liquid crystal materials. |