Lawesson's reagent → Ethyl 5-amino-2-phenyl-1,3-thiazole-4-carboxylate

HRID 2088420Notes

Reaction equation

HRID 2088420 reaction equation
[C:1]([NH:9][CH:10]([C:16]#[N:17])[C:11]([O:13][CH2:14][CH3:15])=[O:12])(=O)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.COC1C=CC(P2(SP(C3C=CC(OC)=CC=3)(=S)S2)=[S:27])=CC=1>N1C=CC=CC=1>[NH2:17][C:16]1[S:27][C:1]([C:2]2[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=2)=[N:9][C:10]=1[C:11]([O:13][CH2:14][CH3:15])=[O:12]

Participants

4

Reactant 2

HCID 87949Lawesson's reagentHCID 3844040HCID 3844040, compound

Product 1

HCID 13514498Ethyl 5-amino-2-phenyl-1,3-thiazole-4-carboxylateYield 40.3%

Reagents, catalysts & solvents 1

HCID 1049PyridineSolvent

Procedure

To a stirred solution of compound ethyl 2-benzamido-2-cyanoacetate (0.46 g, 2 mmol) in pyridine (20 mL) was added Lawesson's reagent (0.81 g, 2 mmol). The reaction mixture was heated at reflux for 15 hr. It was then concentrated and diluted with EtOAc (40 mL). The diluted mixture was washed with water (3×20 mL), brine (10 mL), dried over Na2SO4, filtered, and concentrated in vacuo. The residue was purified by silica gel column chromatography (10:1 PE/EtOAc) to afford ethyl 5-amino-2-phenylthiazole-4-carboxylate (0.2 g, 40%) as yellow solid: 1H-NMR (CDCl3, 500 MHz) δ (ppm): 7.80 (d, J=6.5 Hz, 1H), 7.36-7.41 (m, 3H), 4.43 (q, J=7.0 Hz, 2H), 1.44 (t, J=7.0 Hz, 3H); MS (ESI) m/z: 249 [M+H+].

Workup

  1. temperatureThe reaction mixture was heated
  2. temperatureat reflux for 15 hr
  3. concentrationIt was then concentrated
  4. additiondiluted with EtOAc (40 mL)
  5. washThe diluted mixture was washed with water (3×20 mL), brine (10 mL)
  6. dry with materialdried over Na2SO4
  7. filtrationfiltered
  8. concentrationconcentrated in vacuo
  9. customThe residue was purified by silica gel column chromatography (10:1 PE/EtOAc)

Sources & evidence

ORD record
ord-21386de65a0545d1b5489656e1825061
Source dataset
uspto-grants-2013_05
Patent number
US08435976B2

Reaction notes

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