Bromination of 2, 7′-bi-indolyls and quinazolin-7-ones. Issue 47 (25th November 2015)

• Record Type: Journal Article
• Authors: Mielczarek, Marcin; Bhadbhade, Mohan; Chen, Rui; Kumar, Naresh; Black, David StC.
• Is Part Of: Tetrahedron. Volume 71:Issue 47(2015)
• Page Start: 8925
• Page End: 8942
• Publication Date: 2015-11-25
• Subjects: Bromination -- 2, 7′-Bi-indolyls -- Quinazolin-7-ones -- Tetra-indolyls -- Macrocycles -- Regioselectivity; MXPRUJMUWUWMRI-UHFFFAOYSA-N -- ZEVYSLFCORBVNV-UHFFFAOYSA-N -- XWTQGTNDQLBEOE-UHFFFAOYSA-N -- HCRIBNGWWVZARK-UHFFFAOYSA-N -- BNRSFXFFKQAYAH-UHFFFAOYSA-N -- GYRRNQXBRNDKKL-UHFFFAOYSA-N -- LAKYEFRGZDABLC-UHFFFAOYSA-N -- OBFFYRYJARUILI-UHFFFAOYSA-N -- LIIKVKYDMIFENR-UHFFFAOYSA-N -- PWCXINPWBUGURN-UHFFFAOYSA-N -- NEISCXKBWBHVNY-UHFFFAOYSA-N -- XPAIRRUZGJIJPM-UHFFFAOYSA-N -- SCLDHHAMONCYLQ-UHFFFAOYSA-N -- NCORUKATLKJTIE-UHFFFAOYSA-N; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tet.2015.09.064
• Languages: English
• ISSNs: 0040-4020

Abstract

Abstract: Efficient regioselective procedures for bromination of 2, 7′-bi-indolyls and quinazolin-7-ones using molecular bromine and N -bromosuccinimide were developed to afford a wide range of novel mono-, di-, tri- and tetrabrominated derivatives with various substitution patterns. Protection of the nitrogen atoms in the 2, 7′-bi-indolyl scaffold by acetyl, benzenesulfonyl and carbonyl groups was investigated. Stability of 2, 7′-bi-indolyls in the presence of strong bases was explored to discover formation of imines followed by the unusual ring opening reaction. Single crystal X-ray crystallography and NMR spectroscopy were employed in order to assign structural isomers of dibrominated quinazolin-7-ones. A new method for the synthesis of macrocyclic tetra-indolyls via acid-catalyzed coupling of monobromo-2, 7′-bi-indolyls is reported and a possible mechanism of the reaction presented. Graphical abstract: