Palladium-Catalyzed Annulation of Diarylamines with Olefins through CH Activation: Direct Access to N-Arylindoles

• Published in: Angewandte Chemie International Edition Vol. 53; no. 44; pp. 11895 - 11899
• Main Authors: Sharma, Upendra, Kancherla, Rajesh, Naveen, Togati, Agasti, Soumitra, Maiti, Debabrata
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 27.10.2014; WILEY‐VCH Verlag; Wiley
• Subjects: Activation; Chemical reactions; Chemistry; Chemistry, Multidisciplinary; cyclization; CH activation; Dehydrogenation; Indoles; Insertion; Joining; Olefins; Organic chemistry; palladium; Physical Sciences; reaction mechanisms; Science & Technology; Synthesis; ENANTIOSELECTIVE SYNTHESIS; CRYSTAL-STRUCTURE; BOND FUNCTIONALIZATIONS; reaction mechanisms; DOMINO SYNTHESIS; INTERNAL ALKYNES; cyclization; STEREOSELECTIVE NITRATION; indoles; C-H activation; FISCHER INDOLE SYNTHESIS; palladium; AROMATIC SUBSTITUTION; OXIDATIVE CYCLIZATION; COPPER CATALYST; CH activation
• ISSN: 1433-7851; 1521-3773; 1521-3773
• DOI: 10.1002/anie.201406284

A palladium‐catalyzed dehydrogenative coupling between diarylamines and olefins has been discovered for the synthesis of substituted indoles. This intermolecular annulation approach incorporates readily available olefins for the first time and obviates the need of any additional directing group. An ortho palladation, olefin coordination, and β‐migratory insertion sequence has been proposed for the generation of olefinated intermediate, which is found to produce the expected indole moiety. No group help needed: A palladium‐catalyzed dehydrogenative coupling between diarylamines and olefins has been discovered for the synthesis of substituted indoles. This intermolecular annulation approach incorporates readily available olefins and obviates the need for any additional directing group. An ortho palladation, olefin coordination, and β‐migratory insertion sequence has been proposed for the generation of an olefinated intermediate.