molecules Article [3+2] Cycloaddition Cycloaddition of of Tosylmethyl Tosylmethyl Isocyanide withwith Styrylisoxazoles: Facile Facile Access to Polysubstituted 3- (Isoxazol-5-yl)pyrroles3-(Isoxazol-5-yl)pyrroles Xueming Zhang 1,, Xianxiu Xianxiu Xu Xu 22 andand Dawei Dawei Zhang Zhang 1,1,** 1 1 CollegeCollege of of Chemistry, Chemistry, Jilin Jilin University University,, Changchun Changchun 130012, 130012, China; China;
[email protected] [email protected] 2 2 CollegeCollege of of Chemistry, Chemistry, Chemical Chemical Engineering Engineering and and Materials Materials Science, Science, Key Key Laboratory Laboratory of of Molecular Molecular and and NanoNano Probes, Probes, Ministry Ministry of of Education, Education, Shan Shandongdong Normal Normal University, University, Jinan Jinan 250014, 250014, China; China;
[email protected]@sdnu.edu.cn * Correspondence:Correspondence:
[email protected];
[email protected]; Tel.: Tel.: +86-431-878-36471 +86-431-878-36471 Received: 16 June 2017; Accepted: 3 3 July July 2017; Published: 7 7 July July 2017 2017 Abstract: A facile access to polysubstitutedpolysubstituted 3-(isoxazol-5-yl)pyrroles3-(isoxazol-5-yl)pyrroles was developed through [3+2] cycloaddition of of tosylmethyl isocyanide isocyanide (TosMIC) (TosMIC) and styrylisoxazoles. In In the the presence presence of of KOH, KOH, various styrylisoxazolesstyrylisoxazoles reactedreacted smoothly smoothly with with tosylmethyl tosylmethyl isocyanide isocyanide and and analogs analogs to deliver to deliver a wide a widerange range of 3-(isoxazol-5-yl)pyrroles of 3-(isoxazol-5-yl)pyrroles at ambient at ambient temperature. temperature. This This transformation transformation isis operationally simple, high-yielding, and displays broad substrate scope. Keywords: isoxazol-5-ylpyrroles;isoxazol-5-ylpyrroles; [3+2]cycloaddition; TosMIC; TosMIC; 3-methyl-4-nitro-5-styrylisoxazoles 1.