Department of Chemistry
Indian Institute of Technology Madras, Chennai-600036
Research Colloquium
Transition-metal-catalyzed amide directed dehydrogenation and site-
selective functionalization of olefins
Name: Keerthana M S Date & Time: 20-09-2023, 3.00-4.00 pm
Guide: Prof. M. Jeganmohan
Venue: CB310, Seminar Hall, Department of Chemistry
Abstract:
Alkenes are essential structural motifs present in various biologically active natural productsand are versatile building blocks in organic synthesis. The selective synthesis and direct functionalization of alkenes represents the most straight forward way to access synthetically valuable alkenes from simpler ones.1 With our continuous interest on developing new synthetic transformations, we have demonstrated a Pd(II)-catalyzed α, β-dehydrogenation of
aliphatic amides using a reusable 8-aminoquinoline bidentate directing group.2a Further, the protocol was explored for the dehydrogenation of least acidic acids and native amides to
synthesise a broad spectrum of conjugated dienamides and dienoic acids.2b Pertinent to the present research, the selective C(alkenyl)H functionalization of unactivated alkenes continued to be a significant challenge due to the very subtle difference in terms of their bond
strength and electronic properties. Realising the need of a viable synthetic transformation for selective alkene functionalization, we have demonstrated a site-selective C(alkenyl)H
functionalization of unactivated alkenes with vinyl cyclopropanes with the assistance of a strong bidentate directing group under palladium catalysis. Further, the protocol was explored for the selective ring opening of vinylcyclopropanes with unactivated alkenes with
predictable and tuneable selectivity by using weakly coordinating native amides. On the other hand, we have also investigated on cobalt(III)-catalyzed redox-neutral coupling of acrylamides with activated alkenes via C–H bond activation.2c
References:
[1]. a) Yang, L.; Li, P.; Wang, F.; Xingwei, L. Org. Chem. Front., 2021, 8, 1085–1101. b) Giri, R.; Shi, B. F.; Engle, K. M.; Maugel, N.; Yu, J. Q. Chem. Soc. Rev., 2009, 38, 3242– 3272. c) Rej, S.; Ano, Y.; Chatani, N.; Chem.Rev. 2023, 123, 7692−7760.
[2] a) Keerthana, M. S.; Jeganmohan, M. J. Org. Chem., 2022, 87, 4873-4882. b) Keerthana M. S.; Jeganmohan, M. Chem. Commun., 2022, 58, 8814–8817. c) Keerthana, M.S.; Manoharan, R.; Jeganmohan, M. Synthesis, 2020, 52, 1625–1633 (Invited manuscript).