C–H Bond Functionalization Under Metalation–Deprotonation Process: Regioselective Direct Arylation of 3-Aminoimidazo[1,2-a]pyrazine
摘要:
Concerted metalation deprotonation (CMD) approach with appropriate proton shuttle precursor, base, and solvent (PivOH-K2CO3-toluene) has rendered a regioselective Pd-catalyzed C6-arylation of 3-aminoimidazo[1,2-a]pyrazine, a therapeutically relevant scaffold accessible by multicomponent reaction. The arylation of this heteroarene suffers from competing C5 and C2'-arylation reactions, while the developed process has virtually eliminated these competing arylations. Density functional calculations for CMD C-H activation at C6, C5, C8, and C2' sites imply that the energy barrier with distortion energy penalty as major contributing component influences the regioselectivity.
[DE] SUBSTANZBIBLIOTHEK ENTHALTEND BICYCLISCHE IMIDAZO-5-YL-AMINE UND/ODER BICYCLISCHE IMIDAZO-3-YL-AMINE<br/>[EN] SUBSTANCE LIBRARY CONTAINING BICYCLIC IMIDAZO-5-YL-AMINES AND/OR BICYCLIC IMIDAZO-3-YL-AMINES<br/>[FR] BIBLIOTHEQUE DE SUBSTANCES CONTENANT DES IMIDAZO-5-YL-AMINES BICYCIQUES ET/OU DES IMIDAZO-3-YL-AMINES BICYCLIQUES
申请人:GRUENENTHAL GMBH
公开号:WO2001027119A2
公开(公告)日:2001-04-19
Substanzbibliothek enthaltend bicyclische Imidazo-5-yl-amine und/oder bicyclische Imidazo-3-yl-amine der allgemeinen Formeln (I) bzw. (II), ein Verfahren zur Herstellung dieser Substanzbibliothek sowie die Verwendung von Substanzen aus dieser Substanzbibliothek zur Herstellung eines Arzneimittels zur Behandlung von Schmerz.