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Updated: Sep 23, 2025

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
Published on: January 19, 2016
TfOH mediated intermolecular electrocyclization for the synthesis of pyrazolines and its application in alkaloid
Sesuraj Babiola Annes1, Pothiappan Vairaprakash1, Subburethinam Ramesh1
1Department of Chemistry, School of Chemical and Biotechnology, SASTRA Deemed University Thanjavur Tamil Nadu India vairaprakash@scbt.sastra.edu ramesh_s@scbt.sastra.edu +91-4362-264120 +91-4362-264101-3614 +91-4362-264101-3791.
Abstract:
TfOH mediated easy access to interesting pyrazolines starting from an aldehyde, phenylhydrazine and styrene has been developed. The scope of this synthetic methodology has been explored by synthesizing various 1,3,5-trisubstituted pyrazolines in very good yields with very high regioselectivity. The origin of regioselectivity has been explained by comparing the stability of possible intermediate carbocations. The synthetic utility of a green solvent has been explored by synthesizing some of pyrazolines in a DES medium. The synthetic application of the present methodology is employed in the synthesis of a pyrazoline alkaloid.
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