Water → Ethyl 2-cyano-3-(7,8-dimethoxy-2H-1-benzopyran-5-yl)propenoate

HRID 34469Notes

Reaction equation

HRID 34469 reaction equation
[CH2:1]([O:3][C:4](=[O:8])[CH2:5][C:6]#[N:7])[CH3:2].[CH3:9][O:10][C:11]1[CH:20]=[C:19]([CH:21]=O)[C:14]2[CH:15]=[CH:16][CH2:17][O:18][C:13]=2[C:12]=1[O:23][CH3:24].N1CCCCC1.O>C1C=CC=CC=1.C(O)(=O)C>[C:6]([C:5](=[CH:21][C:19]1[C:14]2[CH:15]=[CH:16][CH2:17][O:18][C:13]=2[C:12]([O:23][CH3:24])=[C:11]([O:10][CH3:9])[CH:20]=1)[C:4]([O:3][CH2:1][CH3:2])=[O:8])#[N:7]

Participants

7

Reactant 4

HCID 962WaterHCID 7764Ethyl cyanoacetateHCID 8082PiperidineHCID 128498327,8-Dimethoxy-5-formyl-2H-1-benzopyran

Product 1

HCID 54507081Ethyl 2-cyano-3-(7,8-dimethoxy-2H-1-benzopyran-5-yl)propenoateYield 66.9%

Reagents, catalysts & solvents 2

HCID 176Acetic AcidCatalystHCID 241BenzeneSolvent

Procedure

A mixture of ethylcyanoacetate (11.3 g, 0.1 mole), 7,8-dimethoxy-5-formyl-2H-1-benzopyran (22.0 g, 0.1 mole), piperidine (1.02 g, 0.01 mole) and acetic acid (0.36 g, 0.006 mole) in benzene (100 mL) was heated at reflux for 5 hr with azeotropic removal of water and allowed to cool. The solution was extracted successively with water (200 mL), 0.5N hydrochloric acid (200 mL), saturated sodium bicarbonate solution (200 mL), H2O (200 mL) and dried over magnesium sulfate. The volatiles were removed under reduced pressure to give 21.1 g (66.9%) of an orange solid, mp 104.5°-107.5° C.

Workup

  1. temperaturewas heated
  2. temperatureto cool
  3. extractionThe solution was extracted successively with water (200 mL), 0.5N hydrochloric acid (200 mL), saturated sodium bicarbonate solution (200 mL), H2O (200 mL)
  4. dry with materialdried over magnesium sulfate
  5. customThe volatiles were removed under reduced pressure

Sources & evidence

ORD record
ord-aa6a6fa04b4f4744842fb2397954495f
Source dataset
uspto-grants-1988_08
Patent number
US04761475

Reaction notes

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