One-flask synthesis of pyrazolone thioethers involving catalyzed and uncatalyzed thioetherification pathways of
Prasun Mukherjee1, Asish R Das
1Department of Chemistry, University of Calcutta, Kolkata-700009, India. ardchem@caluniv.ac.in ardas66@rediffmail.com.
Abstract:
A one-flask thioetherification of pyrazolones has been demonstrated by transforming several pyrazolones to their corresponding 4-mercaptopyrazolone derivatives and employing them towards cross-coupling with various aromatic and heteroaromatic iodides by applying Pd(OAc)2/xantphos as the catalytic system. The coupling ability of these thiol intermediates with 2,3-dichloropyrazine through an aromatic SN2 pathway has also been established. This methodology provides the use of inexpensive starting materials along with a short reaction time.
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