1436852-75-3Relevant academic research and scientific papers
Three-step synthesis of 3-aryl-2-sulfanylthieno[2,3-b]-, -[2,3-c]-, or -[3,2-c]pyridines from the corresponding aryl(halopyridinyl)methanones
Kobayashi, Kazuhiro,Suzuki, Teruhiko,Egara, Yuko
, p. 69 - 75 (2013/03/13)
A convenient three-step procedure for the synthesis of three types of 3-aryl-2-sulfanylthienopyridines 4, 8, and 12 has been developed. The first step of the synthesis of thieno[2,3-b]pyridine derivatives 4 is the replacement of the halo with a (sulfanylmethyl)sulfanyl group in aryl(2-halopyridin-3-yl) methanones 1 by successive treatment with Na2S×9 H2O and chloromethyl sulfides to give aryl{2-[(sulfanylmethyl)sulfanyl]pyridin-3- yl}methanones 2. In the second step, these were treated with LDA (LiN iPr2) to give 3-aryl-2,3-dihydro-2-sulfanylthieno[2,3-b] pyridin-3-ols 3, which were dehydrated in the last step with SOCl2 in the presence of pyridine to give the desired products. Similarly, thieno[2,3-c]pyridine and thieno[3,2-c]pyridine derivatives, 8 and 12, respectively, can be prepared from aryl(3-chloropyridin-4-yl)methanones 5 and aryl(4-chloropyridin-3-yl)methanones 9, respectively. Copyright
