Molecular Formula | C6H6O2S |
Molar Mass | 142.18 |
Density | 1.365 (estimate) |
Melting Point | 147-149°C(lit.) |
Boling Point | 229.75°C (rough estimate) |
Flash Point | 119.5°C |
Vapor Presure | 0.0027mmHg at 25°C |
Appearance | White to light yellow powder |
BRN | 116184 |
pKa | 3.68±0.10(Predicted) |
Storage Condition | 2-8°C(protect from light) |
Refractive Index | 1.5300 (estimate) |
MDL | MFCD00005438 |
Physical and Chemical Properties | White powder. |
Use | Used as a drug Intermediate |
Hazard Symbols | Xi - Irritant |
Risk Codes | 36/37/38 - Irritating to eyes, respiratory system and skin. |
Safety Description | 24/25 - Avoid contact with skin and eyes. |
WGK Germany | 3 |
HS Code | 29349990 |
Hazard Class | IRRITANT |
introduction | 3-methyl thiophene-2-carboxylic acid is also called 3-methyl -2-thiopheneic acid, which is useful as an intermediate in the manufacture of medicines or pesticides. 3-Methylthiophene-2-carboxylic acid can be used to prepare thiophene compounds 3-methyl -4, 5-dichlorothiophene-2-carboxylic acid. 3-Methylthiophene-2-carboxylic acid can be prepared from 2-chloro-3-methylthiophene through a two-step reaction. |
preparation | 11.8g of magnesium and 250mL of tetrahydrofuran were added to a four-mouth flask with a stirrer, thermometer, cooling pipe and drip funnel under nitrogen atmosphere, and then 2.05g of bromoethane was added to react under heating reflux for 15 minutes. Then, a mixture of 50g 2-chloro-3-methylthiophene and 4.1g bromoethane is added dropwise while maintaining the reflux state, and the mixture is allowed to react under heating reflux for 30 minutes. Then, 4.11g bromoethane was added and allowed to react under heating reflux for 1 hour. Carbon dioxide was introduced into the resulting reaction solution at 25 to 35 ° C. and was allowed to react at room temperature for 2 hours. Add water to the obtained reaction solution, then add concentrated hydrochloric acid, and adjust the reaction solution to a pH value of 2 or less. Then, the water layer was removed by liquid separation, water was added to the resulting organic layer, and the solvent was removed by distillation, thereby obtaining a slurry of 3-methyl-2-thienoic acid. The obtained slurry was filtered and dried to obtain 50.5 g3-methylthiophene-2-carboxylic acid. |
chemical properties | white powder. |
Use | Used as a pharmaceutical intermediate |
NIST chemical information | Information provided by: webbook.nist.gov (external link) |