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An efficient iodide ion (I−)-enabled method for direct α-C(sp3)–H triazolization of ethers via a radical cross-coupling has been developed for regioselective construction of N2-substituted hemiaminal ethers. The developed C(sp3)–H triazolization reaction features the resulting products in good yields (up to 90%) and an excellent functional group tolerance to various ethers, including cyclic and linear ethers. Preliminary mechanistic study and DFT calculation investigation indicate that the reaction proceeds via a SN2-like desulfonylation radical coupling process and an (I−)-involved ternary complex is responsible for the high conversion ratio and the high regioselectivity. I− not only promotes the process but also prevents the in situ generated carbon-centered radicals (CCRs) from being oxidized into carbon cations in an oxidative environment. [ABSTRACT FROM AUTHOR]

Both isoindolinones and continuous quaternary carbons play important roles in pharmaceutical scaffolds. However, few examples have been developed to construct isoindolinones containing continuous quaternary carbons due to the steric hindrance effect. Here, a rhodium(II)-catalyzed reaction of 3-hydroxyisoindolinones and diazos via an intermolecular OH transfer to deliver the isoindolinone derivatives containing continuous quaternary carbons as products is developed in high yields of up to 89% via an intermolecular OH transfer with a green chemistry metric E-factor of 5.70. The resulting products exhibit antiviral activity against SARS-CoV-2 3CL protease (3CLpro) and control investigations show that the quaternary carbons and hydroxyl group are essential for the bioactivity. [ABSTRACT FROM AUTHOR]

A Rh(II)/boron reagent co-catalyzed unprecedent transformation was established for the rapid construction of multi-substituted conjugated dienones under mild conditions by trapping allene carbocations with oxonium ylides from simple starting points in yields up to 85%. Two C＝C double bonds, one C–C and one C–O single bond were built in this one-pot reaction. The diversity-oriented strategy was also established to synthesize alkyne ether and dihydrofuran derivatives by a substrate-depended fashion. [ABSTRACT FROM AUTHOR]

The first example of chiral secondary amine and iridium(i) co-catalyzed enantioselective three-component reaction of aryldiazoacetates, indoles and enals was rationally designed and developed to afford 3-substituted indole derivatives in good yields and with moderate diastereoselectivity as well as excellent enantioselectivity. This reaction is proposed to proceed through the enantioselective trapping of iridium(i)-associated zwitterionic intermediates via selective 1,4-addtition to the chiral amine activated enals. [ABSTRACT FROM AUTHOR]

Highly chemoselective and enantioselective one-pot reactions involved in the oxidative functionalization of Csp3–H bonds adjacent to nitrogen atoms in N-aryl glycine esters were developed. The method provided rapid access to a variety of highly functionalized β-hydroxyl-α-amino acid derivatives from simple starting materials under mild conditions. [ABSTRACT FROM AUTHOR]

A highly enantioselective trapping of protic phosphoramidate ammonium ylides with α-imino esters is reported. The intriguing Rh2(OAc)4 and chiral Brønsted acid co-catalyzed three-component Mannich-type reaction of a diazo compound, a phosphoramidate, and an α-imino ester provides a rapid and efficient access to 2,3-diaminosuccinic acid derivatives with a high level control of diastereo- and enantioselectivity. [ABSTRACT FROM AUTHOR]

An enantioselective four-component reaction of a diazoketone, water, an aniline and ethyl glyoxylate in the presence of catalytic Rh2(OAc)4 and a chiral Brønsted acid was developed to efficiently produce β-hydroxy-α-amino acid derivatives in good yields with high diastereoselectivity and enantioselectivity. [ABSTRACT FROM AUTHOR]

Highly chemoselective and enantioselective one-pot reactions involved in the oxidative functionalization of C sp 3 -H bonds adjacent to nitrogen atoms in N-aryl glycine esters were developed. The method provided rapid access to a variety of highly functionalized β-hydroxyl-α-amino acid derivatives from simple starting materials under mild conditions.

Four-component Mannich reactions subsequently followed by an intramolecular oxo-Michael addition were developed to efficiently produce chiral cyclic acetals with high diastereoselectivity and enantioselectivity.