Cu-Catalyzed highly selective reductive functionalization of 1,3-diene using H2O as a stoichiometric hydrogen atom donor

Cobalt-Catalyzed Z to E Geometrical Isomerization of 1,3-Dienes

An efficient cobalt-catalyzed geometrical isomerization of 1,3-dienes is described. In the combination of a CoCl₂ precatalyst with an amido-diphosphine-oxazoline ligand, the geometrical isomerization of E/Z mixtures of 1,3-dienes proceed in a stereoconvergent manner, affording (E) isomers in high stereoselectivity. This facile transformation features a broad substrate scope with good functional group tolerance and could be scaled up to the gram scale smoothly with a catalyst loading of 1 mol %.

Copper-Catalyzed Highly Selective Protoboration of CF3 -Containing 1,3-Dienes

The copper-catalyzed highly selective protoboration of CF₃ -containing conjugated diene with proton source and B₂ Pin₂ has been developed. This chemistry could suppress the well-known defluorination and provide borated reagents with an intact CF₃ -group. Further studies indicated that the functional group tolerance of this chemistry is very well, and the products could be used as versatile precursors for different types of transformations. Importantly, using chiral diphosphine ligand, we have developed the first example for using such starting material to synthesis allylic boron-reagents which bearing a CF₃ -containing chiral center. Notably, the reaction mechanism was intensively studied by DFT calculations, which could reveal the reason that defluorination was inhibited.

Nickel-catalyzed alkenylboration of alkenylarenes to access homoallylic boronic esters

A practical nickel-catalyzed alkenylboration of alkenylarenes with excellent chemo- and regio-selectivity has been developed.

Nickel-Catalyzed Highly Selective Hydroalkenylation of Alkenyl Boronic Esters to Access Allyl Boron

Allyl boron derivatives are valuable building blocks in the synthesis of natural products and bioactive molecules. Herein, a practical strategy of nickel-catalyzed highly selective hydroalkenylation of alkenyl boronic esters was developed. Under the mild reaction conditions, a variety of allyl boronic esters were accessed with excellent chemo- and regioselectivity. The mechanism of this transformation was illustrated by control experiments and kinetic studies.

Copper and palladium co-catalyzed highly regio-selective 1,2-hydroarylation of terminal 1,3-dienes

A practical copper and palladium co-catalyzed highly regio-selective hydroarylation of terminal 1,3-dienes has been developed. This chemistry afforded the terminal alkenyl group containing products, which are a kind of versatile precursor for organic synthesis, from 1,3-dienes by a practical one-step reaction. With good functional group tolerance, this protocol could be used to make a series of bio-active compounds using readily accessible starting materials. The mechanism of this reaction was explored by control experiments and kinetics studies.

Cu-Catalyzed highly regioselective 1,2-hydrocarboxylation of 1,3-dienes with CO2

A practical copper-catalyzed highly regioselective 1,2-hydrocarboxylation of terminal 1,3-diene with carbon dioxide has been developed. Under mild reaction conditions, this chemistry afforded 2-benzyl-β,γ-unsaturated acid derivatives as products, which are a kind of important unit for bio-active molecules and versatile precursors for organic synthesis, with good functional group tolerance. The key intermediate in this transformation is illustrated by control experiments.