HuagongsheHuagongshe Chemistry Print Report · For research reference only
Phosphoric Acid → 3,4-Dihydro-6-hydroxy-2,5,7,8-tetramethyl-2H-1-benzopyran-2-carbonitrile
Participants
| Role | Name | HCID | Charge |
|---|---|---|---|
| Reactant | Phosphoric Acid | HCID 1004 | — |
| Reactant | Boron trifluoride | HCID 6356 | — |
| Reactant | 4-Hydroxy-2,3,6-trimethylphenyl acetate | HCID 119024 | — |
| Reactant | 6-Acetoxy-2,5,7,8-tetramethyl-2-cyanochromane | HCID 14415675 | — |
| Reactant | Methylvinyl ketone cyanohydrin | HCID 23317073 | — |
| Product | 3,4-Dihydro-6-hydroxy-2,5,7,8-tetramethyl-2H-1-benzopyran-2-carbonitrile | HCID 11680237 | 15% |
Reaction Steps
Using the method described in Example 1, last paragraph, 25.0 g (0.129 mole) of 4-acetoxy-2,3,5-trimethylphenol were reacted with 12.3 g (0.129 mole) of methyl vinyl ketone cyanohydrin, stabilized with phosphoric acid, and with 13.3 g (0.129 mole) of BF3. Conventional working up of the reaction mixture gave, according to analysis by gas chromatography, 25% of 6-acetoxy-2,5,7,8-tetramethyl-2-cyanochromane; colorless crystals, melting point 149°-151° C. In addition, 15% of 6-hydroxy-2,5,7,8-tetramethyl-2-cyanochromane were obtained.
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
|---|---|
| Patent number | US04268446 |
| Source dataset | uspto-grants-1981_05 |
| ORD ID | ord-1dc89288a4c74d72b98ee03e5df95ad9 |
| Source note | uspto-grants-1981_05 |