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SummaryA diphenylphosphinite cellulose palladium complex (Cell–OPPh2–Pd0) was found to be a highly efficient heterogeneous catalyst for the Suzuki–Miyaura reaction. The products were obtained in good to excellent yield under mild reaction conditions. Moreover, the catalyst could be easily recovered by simple filtration and reused for at least 6 cycles without losing its activity.

The Au -catalyzed reaction of 2-(1-alkynyl)-2-alken-1-ones with azomethine imines regio- and diastereoselectively affords furo[3,4-d]tetrahydropyridazines in a tandem cyclization/intermolecular [3+3]-cycloaddition process under mild conditions. By employing a chiral gold catalyst (prepared in situ from a Taddol-derived phosphine-phosphite ligand, Me SAuCl, and AgOTf) high yields and enantioselectivities (up to 94 % yield, up to 96 % ee) are obtained. The method provides an efficient modular route to substituted heterotricyclic furan derivatives and can be easily scaled up (using catalyst loads of only 0.15 mol %).

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γ-Aminobutyric acid is a major inhibitory neurotransmitter in the mammalian central nervous system that plays a substantial role in brain disorders. γ-Amino phosphonic acid is an unique surrogate of both natural and unnatural γ-amino acid. Because of their unique biological activity, γ-Amino acid, as well as γ-amino phosphonic acid derivatives have attracted considerable attentions. However, efficient and straightforward method for constructing chiral γ-substituted-γ-amino acid and γ-amino phosphonic acid derivatives remains a longstanding challenge. Herein, a highly efficient, versatile and universal Cu-catalyzed asymmetric hydroamination of cinnamyl esters, cinnamyl phosphonates and cinnamyl phosphine oxides is presented for accessing γ-amino acid and γ-amino phosphonic acid derivatives in good yields with high level of enantiocontrollings and regioselectivities.

A novel one-pot synthesis of biaryl derivatives has been developed starting from bromobenzaldehyde and phenylboronic acid in the presence of activated methylene compounds via sequential Suzuki coupling/Knoevenagel condensation in aqueous isopropanol medium at room temperature. Significantly, this strategy afforded a straightforward and efficient approach to construct original biaryls in which a new carbon double bond bound to activated moieties such as nitrile, ester and amide is formed from three simple substrates in a one-pot procedure. Moreover, a wide scope of substrates could effectively participate in the process affording the target products in moderate to excellent yields.

Comprehensive Summary An efficient and practical synthesis of heterocyclic nucleosides is developed by a catalyst‐free highly regioselective and diastereoselective [3+2] annulation of α‐purine‐substituted acrylates with nitrones. The reaction operates with excellent functional group tolerance, very mild reaction conditions, and with the green, sustainable, and eco‐friendly 2‐methyltetrahydrofuran (2‐MeTHF) as solvent. Compared with other reactions of electron‐deficient olefin dipolarophiles with nitrones, different regioselective cycloaddition products were observed in this work. This 1,3‐dipolar cycloaddition reaction gives a series of isoxazolidinyl nucleosides in good to excellent yields with promising applications in biochemistry and medicinal chemistry.

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