Herein, we unveiled the novel approach for the synthesis of α-oxoketene S,S- and N,S-acetals employing a Mitsunobuprotocol. A wide range of alcohols has been successfully utilized, enabling great tolerability to this reaction. A diverse set of β-keto(dithioesters/thioamides) bearing various functional groups were found to be well suited substrates for this reaction, showing no obvious electronic effect
An operationally simple and sustainable one-pot photo-oxidative formal [3 + 2] heterocyclization of β-ketothioamides with aryldiazonium salts catalyzed by Ru(bpy)3Cl2 has been realized to provide 2,4-disubstituted 5-imino-1,2,3-thiadiazoles in good to high yields under mild reaction conditions for the first time. The reaction proceeded via an α-phenylhydrazone adduct of thioamides leading to 1,2,3-thiadiazoles
An efficient and versatile copper-catalyzed intermolecular radical [3+2] annulation of thioamides with azobisisobutyronitrile (AIBN) is described. This two-component copper(II)-catalyzed transformation is achieved in one pot via cascade formation of C–S/C–N bonds through cyclization of an in situ generated N,S-acetal intermediate derived from a β-ketothioamide. This operationally simple method allows
Visible-Light-Mediated Synthesis of 1,2,4-Dithiazolidines from β-Ketothioamides through a Hydrogen-Atom-Transfer Photocatalytic Approach of Eosin Y
作者:Monish A. Ansari、Dhananjay Yadav、Sonam Soni、Abhijeet Srivastava、Maya Shankar Singh
DOI:10.1021/acs.joc.9b00406
日期:2019.5.3
ed synthesis of a specific class of 1,2,4-dithiazolidines from β-ketothioamides is devised employing eosin Y as a photoinitiator at ambient temperature in an open pot. The reaction proceeds via an in situ-generated thiyl radical followed by dimerization/deaminative cyclizationcascade, enabling the creation of a dithiazolidine ring through successive formation of S–S and N–C bonds undermetal- and
The Conjugate Addition-Cyclization of 3-Oxoacid Thioanilides to β-Nitrostyrenes. An Efficient Synthesis of Functionalized Thiophenes and their Transformation to Pyrroles
A new and simple method for synthesis of 2-, 3-, and 4-pyridylcarbonyl-2-aryliminothiophene derivatives based on the conjugate addition-cyclization of 3-oxoacid thioamides to β-nitrostyrenes was developed. Thiophene derivatives in acidic medium undergo ring transformation yielding corresponding pyrroles.