1254344-23-4Relevant articles and documents
An efficient and convenient synthesis of 4,5,6,7-tetrahydrothieno[3,2-c] pyridines by a modified Pictet-Spengler reaction via a formyliminium ion intermediate
Kitabatake, Michikazu,Hashimoto, Aki,Saitoh, Toshiaki,Sano, Takehiro,Mohri, Kunihiko,Horiguchi, Yoshie
, p. 1903 - 1921 (2011/04/12)
A synthesis of N-formyl-4,5,6,7-tetrahydrothieno[3,2-c]pyridines (5) was achieved in a highly efficient manner via trifluoroacetic acid catalyzed cyclization of formyliminium ion (4), which was produced by imination of 2-(2-thienyl)ethylamine (1) and a carbonyl compound (2) using titanium(IV) tetraisopropoxide followed by formylation with acetic-formic anhydride in a one-pot procedure. This modified Pictet-Spengler reaction provides a convenient method for preparing 4,5,6,7-tetahydrothieno[3,2-c]pyridines (6) possessing various substituents at C-4. The Japan Institute of Heterocyclic Chemistry.