Weak coordinated nitrogen functionality enabled regioselective C–H alkynylationviaPd(ii)/mono-N-protected amino acid catalysis

Abstract

The exploration of synthetic versatile, while weak coordinated amine derivatives enabled regioselective C‒H functionaliza-tion, remained challenging due to the elusive achievement of reactivity and selectivity simultaneously. Herein, with the assis-tance...

Development of Axially Chiral Styrene-Type Carboxylic Acid Ligands via Palladium-Catalyzed Asymmetric C–H Alkynylation

“…On the basis of the experimental observations and related literature reports, a plausible mechanism for this asymmetric C–H alkynylation reaction was proposed (Scheme ). First, with the coordination of the carboxylate directing group and assistance of the MPAA, deprotonation took place to form the corresponding palladacycle intermediate I .…”

Remote ortho-C–H functionalization via medium-sized cyclopalladation

“…Oxidative coupling of C-H bonds with alkynyl halides has become a convenient method for introducing an alkyne functionality into aromatic compounds. [36][37][38][39][40][41][42] In most of the reported examples, a five-membered metallacycle is involved in the C-H activation process. However, in 2015, Zeng and Zhao reported the ability of the oxalyl amide (OA) as DG in promoting the ortho-alkynylation of phenethylamine and phenylpropylamine derivatives at d and e positions, respectively (Scheme 5).…”

Transition‐Metal‐Catalyzed Selective Alkynylation of C−H Bonds

“…Taking inspiration from Yu's pioneer work [59] on MPAA ( mono ‐ N ‐protected amino acids) accelerated C−H bond functionalizations, Li and co‐workers reported an effective Pd(II)/MPAA catalytic system for the regioselective C−H alkynylation of weakly coordinated amine derivatives [8a] . The general protocol could be applied to amines, imines, and amides, 119 with electron‐donating and electron‐withdrawing substrates yielding the alkynylated products, 120 in moderate to good yields (Scheme 35a).…”