Enantioselective para-C(sp2 )-H Functionalization of Alkyl Benzene Derivatives via Cooperative Catalysis of Gold/Chiral Brønsted Acid.

An asymmetric para-C(sp2 )-H bond functionalization of alkyl benzene derivatives was successfully developed via cooperative catalysis of gold and chiral phosphoric acid (CPA), leading to synthetically useful chiral 1,1-diaryl motifs. Chiral phosphoric acid, ligand, and molecular sieves were found to be crucial for enantioselectivity control of this transformation. The salient features of this protocol include mild conditions, high efficiency, commercially available starting materials, highly chemo- and site- as well as enantioselective aromatic C-H functionalization, broad substrate scope, and extensive applications of the chiral products. The mechanistic studies suggested that two CPAs might be involved in chiral induction.

Dearomative Iodocyclization of N-(o-Alkynyl)aryl Isoindole.

We present a dearomative iodocyclization of N-(o-alkynyl)aryl isoindole here, which affords various biologically active benzoindoleazine skeletons containing alkenyl iodine. The products can further undergo cycloaddition or coupling reactions to afford a series of highly functionalized N-fused polycyclic scaffolds.

Modular and stereoselective synthesis of tetrasubstituted vinyl sulfides leading to a library of AIEgens.

Tetraarylethylenes exhibit intriguing photophysical properties and sulfur atom frequently play a vital role in organic photoelectric materials and biologically active compounds. Tetrasubstituted vinyl sulfides, which include both sulfur atom and tetrasubstituted alkenes motifs, might be a suitable skeleton for the discovery of the new material molecules and drug with unique functions and properties. However, how to modular synthesis these kinds of compounds is still challenging. Herein, a chemo- and stereo-selective Rh(II)-catalyzed [1,4]-acyl rearrangements of α-diazo carbonyl compounds and thioesters has been developed, providing a modular strategy to a library of 63 tetrasubstituted vinyl sulfides. In this transformation, the yield is up to 95% and the turnover number is up to 3650. The mechanism of this reaction is investigated by combining experiments and density functional theory calculation. Moreover, the "aggregation-induced emission" effect of tetrasubstituted vinyl sulfides were also investigated, which might useful in functional material, biological imaging and chemicalnsing via structural modification.

Brønsted acid catalysed chemo- and ortho-selective aminomethylation of phenol.

We have developed a Brønsted acid catalysed highly ortho-selective functionalization of free phenols with readily available N,O-acetals under mild conditions, furnishing various corresponding aminomethylated phenol products in moderate to excellent yields. The salient features of this transformation include mild conditions, good substrate scope, excellent ortho-selectivity, high efficiency, and ease of further transformation.

Copper-catalysed ortho-selective C-H bond functionalization of phenols and naphthols with α-aryl-α-diazoesters.

Herein, we reported the first copper-catalyzed highly efficient C(sp2)-H functionalization of unprotected naphthols and phenols with α-aryl-α-diazoesters. In this transformation, CuCl2 efficiently promoted the highly chemo- and site-selective C-H bond functionalization under mild conditions, furnishing diverse phenol derivatives in moderate to excellent yields from readily available starting materials.

Gold-catalyzed intermolecular [4+1] spiroannulation via site-selective aromatic C(sp2)-H functionalization and dearomatization of phenol derivatives.

Herein, we have developed a novel and simple protocol to realize the C-H bond functionalization/dearomatization of naphthols and phenols with ortho-alkynylaryl-α-diazoesters under gold(i) catalysis. In this protocol, various spirocyclic molecules could be obtained in good yields with excellent chemo- and regio-selectivity and moderate to good diastereoselectivity.