A convenient method for the copper(I)-catalyzed arylation of substituted imidazo[1,2-a]pyridine has been developed. This method is applicable to a variety of aryl electrophiles, including bromides, iodides, and triflates. It represents the first general process for C-3 arylation of substituted imidazo[1,2-a]pyridine by Cu(I) catalysis to construct various functionalized imidazo[1,2-a]pyridine core π-systems.

Molecular recognition in water is the basis of numerous biological functions. The key for efficient and selective recognition of an organic drug molecule is to bind both its polar and nonpolar groups. This is achieved by bioreceptors for which specific noncovalent interactions are efficiently used in a hydrophobic pocket. In contrast, most synthetic receptors cannot efficiently bind the neutral, polar groups of drug molecules and, thus, often exhibit poor binding selectivity and affinity. In this research, we report a systematic study on the binding behaviors of three types of macrocyclic hosts (amide naphthotubes, cucurbit[7]uril, and β-cyclodextrin) to 18 model compounds and 13 drug molecules. Our results show that the high desolvation penalty of polar groups of guests is the reason for the relatively low binding affinity of cucurbit[7]uril and β-cyclodextrin. However, amide naphthotubes with a biomimetic cavity bind efficiently and selectively to organic guests through hydrophobic effects and hydrogen bonding. Drug molecules with multiple polar groups can be better accommodated by these naphthotubes. The anti-configured naphthotube show good biocompatibility according to preliminary cell experiments and is capable of enhancing the water solubility of two poorly soluble drug molecules. Therefore, they may have practical applications in pharmaceutical sciences.

A convenient method to synthesize vinylfurans through a palladium‐catalyzed cyclization/1,2‐H shift sequence under mild conditions is described. This is an efficient strategy to synthesize 2‐vinylfurans from ene–yne ketones, and the corresponding products are obtained in good yields.

We have developed an efficient Pd-catalyzed regioselective arylation of substituted imidazo[1,2-a]pyridines with aryl chlorides, which is rarely reported. This methodology has been successfully applied to the synthesis of a variety of substituted imidazo[1,2-a]pyridine core p systems which exhibit a wide range of biological activities in many drugs.

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Diastereodivergent heterocycle synthesis has been recognized as an important tool for drug discovery in recent years, yet strategies based on nickelacycle formation have not been established. Here, we report a NHC-Ni catalyzed highly 1,3- and 1,4-diastereodivergent heterocycle synthesis from enyne, which is achieved by manipulating the enyne N-substituent (allowing switching of selectivity from up to 2:98 to 98:2). The key to success is the efficient diastereodivergent formation of a nickelacyclopentene, with broad enyne scope at mild conditions, which subsequently provides reductive hydroalkenylation, acylation and silylation products on demand. Diastereoisomers which are sterically hard to distinguish or difficult to access by conventional routes are now accessible easily, including those with very similar 4°, contiguous and skipped stereocenters.

NHC-Nickel(0) catalyzed 1,3-and 1,4diastereodivergent hydroacylative heteroenyne cyclization with aldehydes was achieved (Syn-:Anti-, switchable from up to 1:99 to 98:2). Both sets of heterocyclic diastereomers are accessible via this route, with a high γ-:α-enone structure ratio. Preliminary DFT investigations indicated that the manipulation of the N-substituent exerts a direct influence on the diastereoselectivity of NHC-nickelacyclopentene formation. The energy differences associated with the endocyclic bond angle (CÀ ZÀ C) changes noted in the calculations, might possibly account for the broad scope and high diastereodivergent selectivity observed.

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