Carbon Dioxide → Benzopyran

HRID 1030822Notes

Reaction equation

HRID 1030822 reaction equation
[O:1]1[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[CH2:4][CH2:3][CH:2]1O.C(=O)=O>S([O-])([O-])(=O)=O.[Cu+2]>[O:1]1[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[CH:4]=[CH:3][CH2:2]1

Participants

4

Reactant 2

HCID 280Carbon DioxideHCID 11171070Chroman-2-ol

Product 1

HCID 9211Benzopyran

Reagents, catalysts & solvents 1

HCID 24462Copper SulfateCatalyst

Procedure

In 50 cc of anhydrous ether was dissolved 2.78 g (0.01 mole) of the chromanone compound obtained in Example 2, represented by the following formula: ##STR72## and the solution was cooled to 0° C. and 0.012 mole of Grignard reagent CH3MgI newly prepared in 50 cc of anhydrous ether was dropped into the solution over a period of about 1 hour. After termination of the dropwise addition, the mixture was stirred at room temperature for 2 hours and was gradually poured into cold water to extract the product with ether. The ether extract was dried on magnesium sulfate and ether was removed under reduced pressure to form a chromanol compound from the chromanon compound. Then, the obtained chromanol compound was heated at 200° C. together with anhydrous copper sulfate in a carbon dioxide current for about 10 minutes, and the obtained brown viscous liquid was purified by the chromatography on silica gel to obtain 2.24 g of a chromene compound represented by the following formula: ##STR73##

Workup

  1. customthe obtained brown viscous liquid was purified by the chromatography on silica gel

Sources & evidence

ORD record
ord-2b59ec6c26a845ff8818c2ed87760195
Source dataset
uspto-grants-1992_04
Patent number
US05106998

Reaction notes

Loading…