4,5-dihydro-4,4-dimethyl-2-(2-thienyl)-oxazole → HCID 70060418, compound

HRID 1457654Notes

Reaction equation

HRID 1457654 reaction equation
C[C:2]1([CH3:12])[CH2:6][O:5][C:4]([C:7]2[S:8][CH:9]=[CH:10][CH:11]=2)=[N:3]1.[CH2:13]([Li])[CH2:14][CH2:15]C.CN1CC(=O)CC2C=CC=C[C:21]=2[O:20]1>O1CCCC1.CCCCCC>[O:20]=[C:21]1[C:12]2[CH:13]=[CH:14][CH:15]=[CH:6][C:2]=2[NH:3][C:4](=[O:5])[C:7]2[S:8][CH:9]=[CH:10][C:11]1=2

Participants

6

Reactant 3

HCID 50082824,5-dihydro-4,4-dimethyl-2-(2-thienyl)-oxazoleHCID 22099707HCID 22099707, compoundHCID 178418339Butyllithium

Product 1

HCID 70060418HCID 70060418, compound

Reagents, catalysts & solvents 2

HCID 8028TetrahydrofuranSolventHCID 8058HexaneSolvent

Conditions

Temperature
0 °C

Procedure

To a solution of 9.0 g at 4,5-dihydro-4,4-dimethyl-2-(2-thienyl)oxazole in 200 ml of tetrahydrofuran, cooled to -78° C., is added 20 ml of a 2.5 molar solution of n-butyl lithium in hexane. The mixture is stirred -78° C. for 15 minutes and at 0° C. for 30 minutes. To the stirred solution is added 6.0 g of 2-methylbenzoxazepine-4-one. The mixture is stirred at room temperature for 16 hours quenched with ice cold water and extracted with chloroform. The extract is concentrated to dryness and 100 ml of 40% H2SO4 is added. The mixture is refluxed for 4 hours, cooled to room temperature and filtered to give 9,10-dihydro-4,10-dioxo-4H-thieno [2,3-c][1]benzazepine. The solid is washed with water to give 2.5 g of crystals. The solid is dissolved in 100 ml of dry tetrahydrofuran and 1.0 g of lithium aluminum hydride added. The mixture is refluxed for 16 hours, chilled and ice cold water is added dropwise. The mixture after dilution with water is extracted with chloroform-methanol (3:1) and the extract dried (MgSO4). The solvent is removed and the residue chromatographed over silica gel with ethyl acetate-hexane (1:1) as solvent to give 1.8 g of solid; Mass spectrum (CI) 202 (M+H).

Workup

  1. stirringThe mixture is stirred at room temperature for 16 hours
  2. customquenched with ice cold water
  3. extractionextracted with chloroform
  4. concentrationThe extract is concentrated to dryness and 100 ml of 40% H2SO4
  5. additionis added
  6. temperatureThe mixture is refluxed for 4 hours
  7. temperaturecooled to room temperature
  8. filtrationfiltered

Sources & evidence

ORD record
ord-6a72ef3945804182a514333c93790111
Source dataset
uspto-grants-1998_12
Patent number
US05849735

Reaction notes

Loading…