Tandem regioselective synthesis of tetrazoles and related heterocycles using iodine
作者:Ramesh Yella、Nilufa Khatun、Saroj Kumar Rout、Bhisma K. Patel
DOI:10.1039/c0ob01007c
日期:——
carbodiimides). The in situ generated heterocumulene on subsequent treatment with sodium azide at room temperature gave corresponding tetrazoles. The product regioselectivity for unsymmetrical 1,3-disubstituted thioureas was found to be correlated with the basicities (pKa's) of the parent amines attached to the thiourea. Aryl-sec-alkyl unsymmetrical thioureas gave thioamido guanidino products rather than the 5-aminotetrazoles
作者:Shivani Sharma、Ramdas S. Pathare、Antim K. Maurya、Kandasamy Gopal、Tapta Kanchan Roy、Devesh M. Sawant、Ram T. Pardasani
DOI:10.1021/acs.orglett.5b03185
日期:2016.2.5
A ruthenium catalyzedintramolecular C–S coupling reaction of N-arylthioureas for the synthesis of 2-aminobenzothiazoles has been developed. Kinetic, isotope labeling, and computational studies reveal the involvement of an electrophilic ruthenation pathway instead of a direct C–H activation. Stereoelectronic effect of meta-substituents on the N-arylthiourea dictates the final regioselective outcome
A ligand free copper(II) catalyst is as effective as a ligand assisted Pd(II) catalyst towards intramolecular C–S bond formation via C–H functionalization
作者:Arghya Banerjee、Sourav Kumar Santra、Saroj Kumar Rout、Bhisma K. Patel
DOI:10.1016/j.tet.2013.08.025
日期:2013.10
Copper(I) catalysts are usually ineffective on the other hand Pd(II) catalysts are quite effective in promoting intramolecular sp2 C–H functionalization (C–S bond formation). Herein, we have developed a ligand assisted Pd(II) catalyzed C–S bond formation via C–H activation from arylthioureas leading to the formation of 2-aminobenzothiazoles for substrates bearing electron donating (EDG) groups in the