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

HRID 847135

Reaction equation

HRID 847135 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 evaporated under reduced pressure. Following 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 CH2Cl2). The structures of the two isomers were confirmed by NMR. NMR (CDCl3) d 7.56 (1H, d), 7.11 (1H, d), 6.26 (1h, 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. customthen evaporated under reduced pressure
  6. customrecrystallization from ethanol, 79.9 grams
  7. additionof mixed 6

Sources & evidence

ORD record
ord-fea501cf78144f28992b577dd8dae37c
Source dataset
uspto-grants-1992_08
Patent number
US05139940

Linked notes

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