A Pd-catalyzed transfer hydrogenation of various N-heteroaromatic compounds with B2pin2 as a mediator and environmentally benign water as both solvent and hydrogen donor has been disclosed. This reaction proceeded under ambient temperature with a broad range of N-heteroaromatic compounds among which imidazo[1,2-a]pyridine derivatives were for the first time selectively reduced to 5,6,7,8-tetrahydroimidazo[1,2-a]pyridines, which are the core structural motifs of an inhibitor of human O-GlcNAcase. Mechanistic studies suggested that the new protons in products are from water and Pd-H might be the key intermediate with B2pin2 as the H2O activator.

A direct dehydrative coupling of terminal alkynes with allylic alcohols catalyzed by Pd(PPh3)4 with an N,P-ligand assisted by Ti(OiPr)4 has been developed. The coupling reaction tolerates various functional groups, providing a valuable synthetic tool to access 1,4-enynes.

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An enantioselective [3+2] annulation of Morita-Baylis-Hillman carbonates with trifluoropyruvate catalyzed by modified cinchona alkaloids was developed in good to excellent yields with excellent diastereo- and enantioselectivities.

The reaction of Morita-Baylis-Hillman (MBH) alcohols with Me2PhSiBpin under the catalysis of Cu(OTf)2/pyridine in methanol has been developed. The direct silylation of allylic alcohols via dual activation of the Si-B bond and the hydroxyl group of the MBH alcohol provides an efficient and convenient method for the synthesis of functionalized allylsilanes.

An expedient strategy of reductive N-alkylation of amines with readily available carboxylic acids as alkylating reagents has been developed.

HO is routinely described as a proton donor, however, in the presence of diboron compounds, the umpolung reaction of HO under metal-free conditions was successfully developed, which could afford hydride species, leading to a highly efficient and chemoselective reduction of C[double bond, length as m-dash]O bonds. This strategy exhibits excellent chemoselectivities toward carbonyl groups in the presence of ester, olefin, halogen, thioether, sulfonyl, cyano as well as heteroaromatic groups.

An efficient, convenient and mild Ru-catalyzed reductive amination reaction was developed by employing H2O as both hydrogen source and solventviaB2(OH)4/H2O systems. α-Deuterated amines were also obtained expediently by employing D2O in our catalytic systems.