We report herein the first examples of ap alladiumcatalyzede nantioselective Cacchir eaction for the synthesis of indoles bearing ac hiral C2-aryl axis.I nt he presence of ac atalytic amount of Pd(OAc) 2 and (R,R)-QuinoxP* ligand, reaction of N-aryl(alkyl)sulfonyl-2-alkynylanilides with arylboronic acids under oxygen atmosphere afforded enantioenriched 2,3-disubstituted indoles in high yields and enantioselectivity.The indole ring is constructed de novo in this process and ac omplexation-induced chirality transfer is proposed to account for the observed enantioselectivity. Scheme 1. Axially chiral indoles:occurrence and synthesis.Scheme 3. Synthesis and X-ray structural characterization of (L6)PdArX complexes 7a (X = OAc) and 8a (X = I). Scheme 4. Results of control experiments using QuinoxP*(=O) and QuinoxP*(=O) 2 as ligands. Angewandte Chemie Communications 2107

The gold(I)/chiral Brønsted acid relay catalysis enabled a highly stereoselective three-component reaction of salicylaldehydes, anilines, and alkynols to give aromatic spiroacetals in high yields and stereoselectivities.

An asymmetric organocatalytic direct C-H/C-H oxidative coupling reaction of N(1),N(3)-diphenylmalonamides has been well established by using chiral organoiodine compounds as catalysts, wherein four C-H bonds were stereoselectively functionalized to give structurally diverse spirooxindoles with high levels of enantioselectivity. More importantly, the findings indicated that chiral hypervalent organoiodine reagents can serve as alternative catalysts for the creation of enantioselective functionalization of inactive C-H bonds.

Externally yours: 2,3‐Dihydroquinolin‐4(1H)‐ones are obtained in moderate to good yields (40–84 %, see scheme) in a metal‐free oxidation/C(sp3)H functionalization of unactivated aryl alkynes. 2,6‐Dichloropyridine‐N‐oxide is used as an external oxidant. In the reaction, a Brønsted acid, not a metal, plays a key role in the triple CC bond activation.

Chiral indole derivatives are an intriguing class of heterocyclic compounds; their structural motifs are frequently found in natural products and synthetic compounds with significant bioactivity. Among many synthetic transformations leading to the production of enantiopure indole derivatives, chiral phosphoric acid catalyzed reactions are the most attractive methodologies, since these reactions can directly afford enantiomerically pure indole derivatives from readily accessible starting materials under mild conditions. In this review, the most recent achievements in this research area have been gathered and classified according to different reaction types for the synthesis of enantioenriched indole derivatives under the catalysis of chiral phosphoric acids.

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Relay catalysis: An unprecedented protocol for the synthesis of cyclic aminals has been realized under the relay catalysis of a gold(I)/Brønsted acid binary system to generate cyclic aminals in excellent yields of up to 99 % with moderate to high diastereoselectivity (see scheme; up to 95:5 d.r.).

Scheme 1. C(sp 3 )ÀH functionalization by hydride transfer/cyclization sequences, EWG = electron-withdrawing group.Scheme 2. Oxidation/C(sp 3 )ÀH functionalization of unactivated alkynes under gold(I) and metal-free conditions.