Rhodium( III )‐Catalyzed Annulative Carbon–Hydrogen Bond Functionalization

An asymmetric metal-templated route to amino acids with an isoquinolone coreviaa Rh(iii)-catalyzed coupling of aryl hydroxamates with chiral propargylglycine Ni(ii) complexes

“…Among the different strategies to synthesize isoquinolones, 4,5 a Rh( iii )-catalyzed C–H activation/annulation of various readily available aryl hydroxamates with alkynes is one of the most efficient and straightforward approaches. 6,7 In particular, this reaction proved to be a key step in the total synthesis of natural products, such as rosettacin and nauclefine. 8 Recently, in order to construct novel peptide–pharmacophore conjugates, Van der Eycken and co-workers chemoselectively diversified a peptide backbone by introducing an isoquinolone framework via ruthenium-catalyzed C–H activation/annulation; although the reactions were conducted under harsh conditions (copper( ii ) acetate was used as an oxidant at 120 °C under basic conditions), no racemization was observed at the chiral α-AA center.…”

Recent advances in Rh(i)-catalyzed enantioselective C–H functionalization

“…[32][33][34][35][36][37][38][39][40][41][42][43][44][45] From the viewpoint of substrate activation modes, Rh-catalyzed C-H functionalization could be classified into two categories: inner-sphere mechanism and outer-sphere mechanism, which differ in the mechanism of the C-H activation step (Scheme 1). 46,47 Generally, Rh(III)-catalyzed asymmetric C-H functionalization adopts the inner-sphere mechanism by taking advantage of a chiral cyclopentadienyl (Cp) ligand, 35,38,39,[48][49][50][51] whereas Rh(II) usually coordinates with a chiral carboxylic acid to achieve the effect of asymmetric C-H functionalization via the outer-sphere mechanism, 14,[52][53][54] both of which have been well reviewed elsewhere.…”