HuagongsheHuagongshe Chemistry Print Report · For research reference only
Ethyl Acetate → rac-3,4-Dihydro-2,5,7,8-tetramethyl-2-[(3-pyridinyl)ethynyl]-2H-1-benzopyran-6-ol
Participants
| Role | Name | HCID | Charge |
|---|---|---|---|
| Reactant | Ethyl Acetate | HCID 8857 | — |
| Reactant | 3-Bromopyridine | HCID 12286 | — |
| Reactant | rac-3,4-dihydro-2-ethynyl-2,5,7,8-tetramethyl-2H-1-benzopyran-6ol | HCID 14478563 | — |
| Solvent | Dichloromethane | HCID 6344 | — |
| Product | rac-3,4-Dihydro-2,5,7,8-tetramethyl-2-[(3-pyridinyl)ethynyl]-2H-1-benzopyran-6-ol | HCID 15171813 | — |
Reaction Steps
Rac-3,4-dihydro-2-ethynyl-2,5,7,8-tetramethyl-2H-1-benzopyran-6-ol, 4,6g, was reacted as described in Example 4 with 4.74 g of 3-bromopyridine. The reaction time was extended to 18 hours. The product was isolated by chromatography over 150 g of silica gel using 10 % (v/v) of ethyl acetate in methylene chloride for elution. Crystallization of the combined clean fractions from ethyl acetate/hexane gave off-white crystals with m.p. 172°-175° C. The analytical sample was recrystallized from tetrahydrofuran/hexane and had m.p. 175-178° C.
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
|---|---|
| Patent number | US05015661 |
| Source dataset | uspto-grants-1991_05 |
| ORD ID | ord-e83e73986a164ea9b8f1b4f751823c2c |
| Source note | uspto-grants-1991_05 |