Room temperature ICl-induced dehydration/iodination of 1-acyl-5-hydroxy-4,5-dihydro-1H-pyrazoles. a selective route to substituted 1-acyl-4-iodo-1H-pyrazoles.
A number of new functionally substituted 1-acyl-5-hydroxy-4,5-dihydro-1H-pyrazoles have been prepared in moderate to excellent yields from the corresponding 2-alkyn-1-ones. The resulting dihydropyrazoles undergo dehydration and iodination in the presence of ICl and Li2CO3 at room temperature to provide 1-acyl-4-iodo-1H-pyrazoles.
Waldo
Jesse P
JP
Department of Chemistry, Iowa State University, Ames, Iowa 50011, USA.
Mehta
Saurabh
S
Larock
Richard C
RC
D000215:Acylation; D002384:Catalysis; D003300:Copper / Q000737:chemistry; D054879:Halogenation; D006900:Hydroxylation; D016651:Lithium Carbonate / Q000737:chemistry; D008956:Models, Chemical; D010165:Palladium / Q000737:chemistry; D011720:Pyrazoles / Q000138:chemical synthesis*; D013696:Temperature; D014867:Water / Q000737:chemistry
D011720:Pyrazoles; D014867:Water; D016651:Lithium Carbonate; D010165:Palladium; D003300:Copper