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1,3-Diketones from Acid Chlorides and Ketones: A Rapid and General One-Pot Synthesis of Pyrazoles

Stephen T. Heller* and Swaminathan R. Natarajan

*Department of Medicinal Chemistry, Merck Research Laboratories, P.O. Box 2000, Rahway, New Jersey 07065, Email:

S. T. Heller, S. R. Natarajan, Org. Lett., 2006, 8, 2675-2678.

DOI: 10.1021/ol060570p

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1,3-Diketones, which were synthesized in situ from ketones and acid chlorides, were converted into pyrazoles by the addition of hydrazine. This method allows a fast and general synthesis of previously inaccessible pyrazoles and synthetically demanding pyrazole-containing fused rings.

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Key Words



The reaction works just as well with 1 eq of hydrazine (just more slowly in the condensation phase)

Stephen T. Heller, August 8, 2007

ID: J54-Y2006-1870