Enantioselective Direct Synthesis of C3-Hydroxyalkylated Pyrrole via an Amine-Catalyzed Aldol/Paal–Knorr Reaction Sequence
Amol Prakash Pawar, Jyothi Yadav, Atul Jankiram Dolas, Yadav Kacharu Nagare, Eldhose Iype, Krishnan Rangan, Indresh Kumar
Abstract
Creating functionality with chirality at position C3 of pyrrole is challenging. An operationally simple organocatalytic method has been developed to generate functionality with a chiral tertiary/quaternary stereocenter at position C3 of pyrrole. The process proceeds through an amine-catalyzed direct aldol reaction of succinaldehyde with various acceptor carbonyls, followed by a Paal–Knorr reaction with a primary amine in the same pot. A series of chiral C3-hydroxyalkylated N-alkyl/Ar/H-pyrroles have been synthesized for the first time with good to high yields and excellent enantioselectivity.
Topics & Concepts
StereocenterChemistryAldol reactionAmine gas treatingPyrroleCatalysisEnantioselective synthesisOrganocatalysisCombinatorial chemistryAlkylOrganic chemistrySynthesis and Characterization of PyrrolesAsymmetric Synthesis and CatalysisPorphyrin and Phthalocyanine Chemistry