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A novel oxidative cleavage and fluoromethylthiolation reaction of C═C bonds has been developed that represents the first and general method for the preparation of mono-, di-, and trifluoromethylthioesters from alkenes. The protocol features excellent product selectivity and substrate suitability. Various observations suggested that the protocol proceeded via a two-step radical process and that aldehyde was the key intermediate. What's more meaningful is that this route provides a new direction for converting alkenes into higher-value-added carbonyl-containing chemicals.

A direct and efficient palladium-catalyzed oxidative dehydrogenative fluoroalkoxylation of benzaldehydes is reported here for the first time. The method features mild reaction conditions, good tolerance of functional groups, and a broad substrate scope. The protocol employs the transient directing group strategy, thereby avoiding the additional installation and removal of directing groups, endowing the method with great advantages of atom and step economy. The approach should find broad applications in drug synthesis and discovery processes.

An efficient and unprecedented strategy for the synthesis of 1,4-enediones from saturated ketones has been developed via palladium-catalyzed oxidative dehydrogenation. The protocol employs molecular oxygen as the sole oxidant and represents an atom- and step-economic process. The approach showed broad substrate scope, good functional group tolerance, and complete E -stereoselectivity. The reaction mechanism has been investigated through deuterium-labeling experiments and intermediate experiments.

An unprecedented cross-dehydrogenative-coupling (CDC) reaction of saturated aldehyde β-C-H with arenes to form cinnamaldehydes via the cleavages of four C-H bonds has been developed. The reaction possesses complete E-stereoselectivity for the C═C double bond. The protocol is featured by atom and step economy, mild reaction conditions, and convenient operation.

The utilization of the transient directing strategy into the direct oxidative dehydrogenative arylation of aldehydes with arenes was reported for the first time. Featured by mild reaction conditions, good functional group compatibility, and great regioselectivity, the method should find broad applications in new medicine and material development and discovery processes.

A new chemistry of azo compounds that is a radical generation and addition in situ of azocarboxylic tert-butyl esters to synthesize hydrazines has been described. The protocol provides a novel strategy for the synthesis of various hydrazines. The advantages of the transformation include broad substrate scope, benign conditions, and convenient operation.

A palladium-catalyzed asymmetric allyl-allyl cross-coupling reaction to construct the chiral quaternary carbon center of crinane alkaloids has been developed. On the basis of an efficient approach, the enantioselective synthesis of (-)-crinane (1) is presented, and the first asymmetric total synthesis of (+)-4a-dehydroxycrinamabine (2) was achieved by subsequent oxidation, 1,4-conjugate addition, RCM reaction, reductive amination, and Pictet-Spengler reaction. The method provided an alternative strategy for the syntheses of crinane alkaloids and other Amaryllidaceae natural products.

The palladium-catalyzed intramolecular C-H/C-H coupling reaction of two simple arenes to generate 6H-benzo[c]chromenes has been reported for the first time. The approach features broad substrate scope and good tolerance of functional groups and uses molecular oxygen as the terminal oxidant. The high efficiency of the approach is verified by concise total synthesis of natural product cannabinol.

A new chemistry of hydrazines that is a copper-catalyzed radical reaction to synthesize vinyl sulfones from readily available N-tosylhydrazones has been described. The protocol provides a novel strategy for the synthesis of various vinyl sulfones including α, β-disubstituted ones and terminal ones. The advantages of the transformation include excellent E stereoselectivity, broad substrate scope, low cost of reagents, and convenient operation. A novel and efficient one-pot synthesis of alkynes from N-tosylhydrazones has been achieved. The studies provide important complementary approaches for the syntheses of vinyl sulfones and alkynes.

A general and efficient palladium-catalyzed intermolecular direct C-H homocoupling of furans and thiophenes has been developed. The reaction is characterized by using molecular oxygen as the sole oxidant and complete C5-position regioselectivity. Both C2- and C3-substituted furans or thiophenes are appropriate substrates. The approach provides a straightforward, facile, and economical route to bifurans and bithiophenes under mild reaction conditions.

An efficient and economical palladium-catalyzed oxidation system has been identified. The oxidation system, characterized by not adding ligand and using molecular oxygen as the sole oxidant, can realize the Tsuji-Wacker oxidation of terminal olefins and especially styrenes to methyl ketones; in addition, this system can achieve tandem Wacker oxidation-dehydrogenation of terminal olefins to α,β-unsaturated ketones.

A general and efficient palladium-catalyzed intermolecular direct C3 alkenylation of indoles using oxygen as the oxidant has been developed. The reaction is of complete regio- and stereoselectivity. All products are E-isomers at the C3-position, and no Z-isomers or 2-substituted product can be detected.