Highly modular assembly of cationic helical scaffolds: rapid synthesis of diverse helquats via differential quaternization

0345958 - ÚOCHB 2011 RIV GB eng J - Journal Article
Severa, Lukáš - Adriaenssens, Louis - Vávra, Jan - Šaman, David - Císařová, I. - Fiedler, Pavel - Teplý, Filip
Highly modular assembly of cationic helical scaffolds: rapid synthesis of diverse helquats via differential quaternization.
Tetrahedron. Roč. 66, č. 19 (2010), s. 3537-3552. ISSN 0040-4020. E-ISSN 1464-5416
R&D Projects: GA ČR GA203/09/0705; GA ČR GA203/09/1614
Institutional research plan: CEZ:AV0Z40550506
Keywords : helquat * helicene-viologen hybrid * [2+2+2] cycloaddition * extended diquat * N-heteroaromatic cation
Subject RIV: CC - Organic Chemistry
Impact factor: 3.011, year: 2010

A protocol for rapid and highly modular assembly of a diverse set of helquats is described. From a common bis-isoquinoline precursor, two successive distinct pyridine-type nitrogen quaternizations followed by rhodium-catalyzed [2+2+2] cycloaddition afford non-symmetric [7]helquats. This route allows for straightforward molecular editing of cationic helical skeletons as exemplified by the synthesis of 15 different [5]-, [6]-, and [7]helquats. The use of pyridine-type nitrogen as a functionalization handle makes the route exclusively skeleton-building and therefore markedly step economic.
Permanent Link: http://hdl.handle.net/11104/0187115