Chloroform → 8-(beta-Chloroallyl)-7-butyroxy-4-methylcoumarin

HRID 1460127

Reaction equation

HRID 1460127 reaction equation
ClC(=C)CO[C:5]1[CH:14]=[C:13]2[C:8]([C:9](C)=[CH:10][C:11](=[O:15])[O:12]2)=[CH:7][CH:6]=1.[C:18]([O:23][C:24](=[O:28])[CH2:25][CH2:26][CH3:27])(=O)[CH2:19][CH2:20][CH3:21].C(Cl)(Cl)[Cl:30]>C(C1C=CC(C(C)C)=CC=1)(C)C>[Cl:30][C:6](=[CH2:7])[CH2:5][C:14]1[C:13]([O:12][C:11](=[O:15])[CH2:10][CH2:9][CH3:8])=[CH:21][CH:20]=[C:19]2[C:18]=1[O:23][C:24](=[O:28])[CH:25]=[C:26]2[CH3:27]

Participants

5

Reactant 3

HCID 6212ChloroformHCID 7798Butyric anhydrideHCID 11215917-(beta-Chloroallyloxy)-4-methylcoumarin

Product 1

HCID 234469868-(beta-Chloroallyl)-7-butyroxy-4-methylcoumarin

Reagents, catalysts & solvents 1

HCID 74861,4-DiisopropylbenzeneSolvent

Procedure

Rearrangement of CAMC was accomplished in high yield by refluxing the allyl ether from Step 2 (143.5 gm; 0.55 mole) in a mixture of p-diisopropylbenzene (Aldrich, 1000 ml) and butyric anhydride (96 ml, 92.8 gm; 0.59 mol, Aldrich) under argon for 18 hours. The cooled reaction mixture was diluted with chloroform, washed with water and then saturated sodium bicarbonate, dried (MgSO4) then evapaorated under pressure. Folloeing recrystallization from ethanol, 79.9 grams of mixed 6 and 8-(β-chloroallyl)-7-butyroxy-4-methylcoumarin (BCAMC,15) were obtained. HPLC analysis (Beckman; C18-ODS reverse phase column, isocratic elution with 60% CH3OH/40%H2O) showed the mixture to contain 85.7% of the desired 8-substituted isomer, of which a sample was purified by column chromatography (60-200 mesh silica gel, elution with CH2 Cl2). The structures of the two isomers were confined by NMR. NMR (CDCl3) d 7.56 (1H,d), 7.11 (1H,d), 6.26 (1 h,d), 5.05-5.19 (2H, m, 3.84 (2H, m), 2.55-2.62 (2H, m), 2.43 (3H, d), 1.78-1.82 (2H, m), 1.01-1.09 (3H,t).

Workup

  1. customin high yield
  2. customThe cooled reaction mixture
  3. washwashed with water
  4. dry with materialsaturated sodium bicarbonate, dried (MgSO4)
  5. customrecrystallization from ethanol, 79.9 grams
  6. additionof mixed 6

Sources & evidence

ORD record
ord-e2d4e2f529ed4023b68aca6c903b2b33
Source dataset
uspto-grants-1998_12
Patent number
US05854967

Linked notes

Loading…