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Updated: Jun 23, 2026

Preparation of N-(2-alkoxyvinyl)sulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines
Published on: January 3, 2018
Improved synthesis of 3-substituted-4-amino-[3,2-c]-thienopyridines
Kenneth M Engstrom1, Amanda L Baize, Thaddeus S Franczyk
1Global Pharmaceutical R&D, Process Research & Development, Abbott Laboratories, 1401 Sheridan Road, North Chicago, Illinois 60064-6290, USA. kenneth.engstrom@abbott.com
Abstract:
Two syntheses of 3-substituted-4-amino-[3,2-c]thienopyridines have been developed to replace the standard literature route to these compounds, which uses unattractive conditions involving azide and high temperatures. The first synthesis utilizes a Friedel-Crafts reaction as its key ring-forming step, whereas the second route relies on an unprecedented intramolecular reductive cyclization between a nitroolefin and a nitrile as its key ring-forming step. The development and optimization of each 3-substituted-4-amino-[3,2-c]thienopyridine synthesis is discussed and a comparison of the routes is presented.
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