Ethoxalyl chloride → Ethyl 3-benzyl-1,2,4-oxadiazole-5-carboxylate
Reaction equation
[OH:1][NH:2][C:3](=[NH:11])[CH2:4][C:5]1[CH:10]=[CH:9][CH:8]=[CH:7][CH:6]=1.[CH2:12]([O:14][C:15](=[O:19])[C:16](Cl)=O)[CH3:13].C([O-])(O)=O.[Na+]>C(OCC)(=O)C>[CH2:12]([O:14][C:15]([C:16]1[O:1][N:2]=[C:3]([CH2:4][C:5]2[CH:6]=[CH:7][CH:8]=[CH:9][CH:10]=2)[N:11]=1)=[O:19])[CH3:13]Participants
5
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Procedure
To a mixture of N-Hydroxy-2-phenyl-acetamidine (1 g, 6.7 mmol) in 7 mL ethyl acetate was added a solution of Chloro-oxo-acetic acid ethyl ester (1.5 g, 10.7 mmol) in 7 mL ethyl acetate at 0° C. The mixture was stirred for 1.5 h at room temperature and then heated to 80° C. for 2.5 h. The reaction mixture was treated with aq. NaHCO3-solution and extracted with ethyl acetate. The organic layers were dried over MgSO4 and evaporated in vacuo. The crude product was purified by preparative HPLC (Waters Sunfire Prep C18 PBD 5 um, 30×100 mm, 5 to 100% ACN and 0.1% TFA, flow 40ml/min) to yield the title compound. LCMS (method A) RtA=1.938 min; [M+H]+=233.1.