HuagongsheHuagongshe Chemistry Print Report · For research reference only
Bromine → 4-Methylphthalic anhydride
Participants
| Role | Name | HCID | Charge |
|---|---|---|---|
| Reactant | Bromine | HCID 24408 | — |
| Reactant | 3a,4,7,7a-Tetrahydro-5-methyl-1,3-isobenzofurandione | HCID 98496 | — |
| Reactant | Sulfur | HCID 5362487 | — |
| Solvent | Acetic Acid | HCID 176 | — |
| Product | 4-Methylphthalic anhydride | HCID 88069 | 16% |
Reaction Steps
Various processes are known for preparing substituted phthalic anhydrides. In two such processes 4-methyl-1,2,3,6-tetrahydrophthalic anhydride is dehydrogenated either by sulfur or by bromine in acetic acid. Yields of 4-methylphthalic anhydride of 59%-87% are claimed for the former method, while the latter gives only a 16% yield [see IZV. Akad Nauk SSSR, Ser Khim, 6, 1315(1973) English trans. Pg. 1271 and D. Craig, Journal of Am. Chem. Soc., Vol. 72, Pg. 3732 (1950)].
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
|---|---|
| Patent number | US04559405 |
| Source dataset | uspto-grants-1985_12 |
| ORD ID | ord-8043c9a711cc4fb590b64ee7b611348a |
| Source note | uspto-grants-1985_12 |