Phosphorus oxychloride → 7-Chlorofuro[2,3-c]pyridine
Reaction equation
[O:1]1[C:5]2[CH:6]=[CH:7][CH:8]=[N:9][C:4]=2[CH2:3][C:2]1=O.P(Cl)(Cl)([Cl:13])=O>>[Cl:13][C:4]1[N:9]=[CH:8][CH:7]=[C:6]2[CH:3]=[CH:2][O:1][C:5]=12Participants
3
Procedure
Alternatively, furan-3-aldehyde is converted to furan-3-acrylic acid with acetic anhydride and potassium carbonate and the acid converted to the acid azide by first reacting the acid with ethoxycarbonyl chloride and triethylamine to form the acid chloride and then reacting the mixed anhydride with sodium azide in water. The furan-3-acrylic acid azide is then heated in diphenylmethane with tributylamine to a temperature of about 190° C. to about 210° C. to form the furopyridone represented by the formula ##STR11## The furopyridone is allowed to react with phosphorus oxychloride to form 7-chlorofuro[2,3-c]pyridine and the latter is reductively dechlorinated with zinc in acetic acid to provide furo[2,3-c]pyridine.
Sources & evidence
- ORD record
- ord-771b78a5855a49418087940178458a0c