Hypervalent iodine(III)-mediated regioselective N-acylation of 1,3-disubstituted thioureas
C B Singh1, Harisadhan Ghosh, Siva Murru
1Department of Chemistry, Indian Institute of Technology, Guwahati, Assam, India.
Abstract:
Reaction of asymmetrical 1,3-disubstituted thioureas with diacetoxyiodobenzene (DIB) produces regioselectively N-acetylurea in shorter time. Regioselectivity is dependent on the pKa's of the amine attached to the thiourea moiety with acylation taking place toward the amine having a lower pKa. This is the first example of DIB being employed as an N-acetylating agent. A mechanism for this novel transformation is also proposed. Mild reaction conditions, shorter reaction times, high efficiencies, environmentally benign methods, and facile isolation of the desired product make the present methodology a most suitable alternative.
More Related Videos
Related Concept Videos
Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene
Preparation and Reactions of Thiols
Nucleophilic Aromatic Substitution of Aryldiazonium Salts: Aromatic SN1
In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo, or cyano...
Radical Substitution: Hydrogenolysis of Alkyl Halides with Tributyltin Hydride
The bonds formed in this reaction are stronger than the bonds broken, making it energetically favorable. The reaction follows a radical chain mechanism similar to radical halogenation reactions,...
Preparation and Reactions of Sulfides
Amines to Amides: Acylation of Amines
Next, the second equivalent of amine serves as a Brønsted base and deprotonates the quaternary amide...


