Triethylamine → Trans-6-cyano-4-(ethoxycarbonylamino)-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-3-ol

HRID 482710Notes

Reaction equation

HRID 482710 reaction equation
[NH2:1][C@@H:2]1[C:7]2[CH:8]=[C:9]([C:12]#[N:13])[CH:10]=[CH:11][C:6]=2[O:5][C:4]([CH3:15])([CH3:14])[C@H:3]1[OH:16].C(N(CC)CC)C.[CH2:24]([O:26][C:27](Cl)=[O:28])[CH3:25]>ClCCl>[C:12]([C:9]1[CH:10]=[CH:11][C:6]2[O:5][C:4]([CH3:14])([CH3:15])[C@@H:3]([OH:16])[C@H:2]([NH:1][C:27]([O:26][CH2:24][CH3:25])=[O:28])[C:7]=2[CH:8]=1)#[N:13]

Participants

5

Reactant 3

HCID 8471TriethylamineHCID 10928Ethyl chloroformateHCID 10943936(3S,4R)-4-amino-3-hydroxy-2,2-dimethyl-chroman-6-carbonitrile

Product 1

HCID 15634874Trans-6-cyano-4-(ethoxycarbonylamino)-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-3-ol

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

To trans-4-amino-6-cyano-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-3-ol (1.09 g) and triethylamine (0.77 ml) in dichloromethane (20 ml), cooled in an ice bath, was added ethylchloroformate (0.67 ml). The mixture was allowed to attain room temperature and stirred for 2 days. The reaction mixture was washed with water and dried over anhydrous magnesium sulphate. Filtration and evaporation and chromatography (chromatotron, gradient elution: 10-30% Ethyl acetate-pentate) gave one fraction (456 mg) which was recrystallised from ethyl acetate-pentane to give the compound of this example (319 mg); mp 147°-148° C.

Workup

  1. customto attain room temperature
  2. washThe reaction mixture was washed with water
  3. dry with materialdried over anhydrous magnesium sulphate
  4. filtrationFiltration and evaporation and chromatography (chromatotron, gradient elution: 10-30% Ethyl acetate-pentate)
  5. customgave one fraction (456 mg) which
  6. customwas recrystallised from ethyl acetate-pentane
  7. customto give the compound of this example (319 mg)

Sources & evidence

ORD record
ord-20c66d109ee9412f84ce5aa899090ca0
Source dataset
uspto-grants-1986_03
Patent number
US04575511

Reaction notes

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