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Herein, we report a photocatalytic defluorocarboxylation of benzylic C(sp3)–F bonds using formate salts as both a reductant and a carbon dioxide source. A variety of benzyl fluorides, bearing primary or secondary C(sp3)–F bonds, undergo defluorinative carboxylation smoothly with HCOOK. This transition metal-free strategy provides a mild, efficient, and sustainable approach for accessing a series of valuable aryl acetic acids, such as flurbiprofen. This protocol also features low catalyst loading, mild reaction conditions, good functional group tolerance, and ready scalability and sustainability. Mechanistic investigations indicate that a carbon dioxide radical anion (CO2˙−) is generated via hydrogen atom transfer (HAT) and acts as a strong reductant to promote single electron reduction of benzyl fluorides. The following nucleophilic attack of carbanions on CO2, both of which are in situ generated intermediates, delivers the desired products, demonstrating the high efficiency of the CO2 capture process. [ABSTRACT FROM AUTHOR]

Difunctionalizing carboxylation of alkynes with CO2 is a sustainable and important strategy to generate valuable acrylate derivatives from both readily available starting materials. Such protocols, however, always suffer from the use of excess metallic reagents and transition metal residue. Herein, we report the first thio-carboxylation of alkynes with thiophenols and CO2, which is a visible-light-driven and transition metal-free process. In contrast to previous carboxylations of alkynes via two-electron activation of CO2, mechanistic and computational investigations suggest that the single-electron activation of CO2 is involved in the thio-carboxylation, rendering unique β-carboxylation. The following cyclizing acylation affords important thiochromones efficiently. Moreover, the one-pot method features mild reaction conditions (room temperature, 1 atmosphere of CO2), high chemo- and regio-selectivity, easy scalability and facile derivatization of products to bioactive compounds. [ABSTRACT FROM AUTHOR]

The first catalytic hydrocarboxylation of enamides and imines with CO2 to generate valuable α,α‐disubstituted α‐amino acids is reported. Notably, excellent chemo‐ and regio‐selectivity are achieved, significantly different from previous reports on β‐carboxylation of enamides, homocoupling or reduction of imines. Moreover, this transition‐metal‐free procedure exhibits low loading of an inexpensive catalyst, easily available substrates, mild reaction conditions, high efficiency, facile scalability and easy product derivatization, providing great potential for application in organic synthesis, pharmaceutical chemistry, and biochemistry. Catalytic hydrocarboxylation of easily available enamides and imines with one atmosphere of CO2 is realized to generate valuable α,α‐disubstituted α‐amino acids under mild reaction conditions. Notably, excellent chemo‐ and regioselectivity are achieved, significantly different from previous reports. 4CzIPN=1,2,3,5‐Tetrakis(carbazol‐9‐yl)‐4,6‐dicyanobenzene. [ABSTRACT FROM AUTHOR]

The first thiocarboxylation of styrenes and acrylates with CO2 was realized by using visible light as a driving force and catalytic iron salts as promoters. A variety of important β-thioacids were obtained in high yields. This multicomponent reaction proceeds in an atom- and redox-economical manner with broad substrate scope under mild reaction conditions. Notably, high regio-, chemo-, and diasteroselectivity are observed. Mechanistic studies indicate that a radical pathway can account for the unusual regioselectivity. [ABSTRACT FROM AUTHOR]

The first thiocarboxylation of styrenes and acrylates with CO2 was realized by using visible light as a driving force and catalytic iron salts as promoters. A variety of important β-thioacids were obtained in high yields. This multicomponent reaction proceeds in an atom- and redox-economical manner with broad substrate scope under mild reaction conditions. Notably, high regio-, chemo-, and diasteroselectivity are observed. Mechanistic studies indicate that a radical pathway can account for the unusual regioselectivity. [ABSTRACT FROM AUTHOR]

Reported is the first oxy-trifluoromethylation of allylamines with carbon dioxide (CO2) using copper catalysis, thus leading to important CF3-containing 2-oxazolidones. It is also the first time CO2, a nontoxic and easily available greenhouse gas, has been used to tune the difunctionalization of alkenes from amino- to oxy-trifluoromethylation. Of particular note, this multicomponent reaction is highly chemo-, regio-, and diastereoselective under redox-neutral and mild reaction conditions. Moreover, these reactions feature good functional-group tolerance, broad substrate scope, easy scalability and facile product diversification. The important products could also be formed with either spirocycles or two adjacent tetrasubstituted carbon centers. [ABSTRACT FROM AUTHOR]

Reported is the first oxy-trifluoromethylation of allylamines with carbon dioxide (CO2) using copper catalysis, thus leading to important CF3-containing 2-oxazolidones. It is also the first time CO2, a nontoxic and easily available greenhouse gas, has been used to tune the difunctionalization of alkenes from amino- to oxy-trifluoromethylation. Of particular note, this multicomponent reaction is highly chemo-, regio-, and diastereoselective under redox-neutral and mild reaction conditions. Moreover, these reactions feature good functional-group tolerance, broad substrate scope, easy scalability and facile product diversification. The important products could also be formed with either spirocycles or two adjacent tetrasubstituted carbon centers. [ABSTRACT FROM AUTHOR]

The first direct use of carbon dioxide in the lactamization of alkenyl and heteroaryl C−H bonds to synthesize important 2-quinolinones and polyheterocycles in moderate to excellent yields is reported. Carbon dioxide, a nontoxic, inexpensive, and readily available greenhouse gas, acts as an ideal carbonyl source. Importantly, this transition-metal-free and redox-neutral process is eco-friendly and desirable for the pharmaceutical industry. Moreover, these reactions feature a broad substrate scope, good functional group tolerance, facile scalability, and easy product derivatization. [ABSTRACT FROM AUTHOR]

The first thiocarboxylation of styrenes and acrylates with CO2 was realized by using visible light as a driving force and catalytic iron salts as promoters. A variety of important β-thioacids were obtained in high yields. This multicomponent reaction proceeds in an atom- and redox-economical manner with broad substrate scope under mild reaction conditions. Notably, high regio-, chemo-, and diasteroselectivity are observed. Mechanistic studies indicate that a radical pathway can account for the unusual regioselectivity. [ABSTRACT FROM AUTHOR]

The first thiocarboxylation of styrenes and acrylates with CO2 was realized by using visible light as a driving force and catalytic iron salts as promoters. A variety of important β-thioacids were obtained in high yields. This multicomponent reaction proceeds in an atom- and redox-economical manner with broad substrate scope under mild reaction conditions. Notably, high regio-, chemo-, and diasteroselectivity are observed. Mechanistic studies indicate that a radical pathway can account for the unusual regioselectivity. [ABSTRACT FROM AUTHOR]

Reported is the first oxy-trifluoromethylation of allylamines with carbon dioxide (CO2) using copper catalysis, thus leading to important CF3-containing 2-oxazolidones. It is also the first time CO2, a nontoxic and easily available greenhouse gas, has been used to tune the difunctionalization of alkenes from amino- to oxy-trifluoromethylation. Of particular note, this multicomponent reaction is highly chemo-, regio-, and diastereoselective under redox-neutral and mild reaction conditions. Moreover, these reactions feature good functional-group tolerance, broad substrate scope, easy scalability and facile product diversification. The important products could also be formed with either spirocycles or two adjacent tetrasubstituted carbon centers. [ABSTRACT FROM AUTHOR]

Reported is the first oxy-trifluoromethylation of allylamines with carbon dioxide (CO2) using copper catalysis, thus leading to important CF3-containing 2-oxazolidones. It is also the first time CO2, a nontoxic and easily available greenhouse gas, has been used to tune the difunctionalization of alkenes from amino- to oxy-trifluoromethylation. Of particular note, this multicomponent reaction is highly chemo-, regio-, and diastereoselective under redox-neutral and mild reaction conditions. Moreover, these reactions feature good functional-group tolerance, broad substrate scope, easy scalability and facile product diversification. The important products could also be formed with either spirocycles or two adjacent tetrasubstituted carbon centers. [ABSTRACT FROM AUTHOR]

The first catalytic hydrocarboxylation of enamides and imines with CO 2 to generate valuable α,α-disubstituted α-amino acids is reported. Notably, excellent chemo- and regio-selectivity are achieved, significantly different from previous reports on β-carboxylation of enamides, homocoupling or reduction of imines. Moreover, this transition-metal-free procedure exhibits low loading of an inexpensive catalyst, easily available substrates, mild reaction conditions, high efficiency, facile scalability and easy product derivatization, providing great potential for application in organic synthesis, pharmaceutical chemistry, and biochemistry., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The first catalytic lactonization of unactivated aryl C-H bonds with CO 2 to afford important phthalides is reported. Notably, this method features high selectivity, excellent functional group tolerance, smooth scalability, and facile product diversification. DFT calculations reveal that a novel insertion of two CO 2 into the O-Pd bond of a palladacycle might be the key step, providing great potential and a different perspective for carbonylation with CO 2 .

A selective oxy-difluoroalkylation of allylamines with carbon dioxide (CO 2 ) via visible-light photoredox catalysis is reported. These multicomponent reactions are efficient and environmentally friendly to generate a series of important 2-oxazolidinones with functionalized difluoroalkyl groups. The good functional group tolerance, broad substrate scope, easy scalability, mild reaction conditions, and facile functionalization of products provide great potential for application in organic synthesis and pharmaceutical chemistry.

Reported is the first oxy-trifluoromethylation of allylamines with carbon dioxide (CO2 ) using copper catalysis, thus leading to important CF3 -containing 2-oxazolidones. It is also the first time CO2 , a nontoxic and easily available greenhouse gas, has been used to tune the difunctionalization of alkenes from amino- to oxy-trifluoromethylation. Of particular note, this multicomponent reaction is highly chemo-, regio-, and diastereoselective under redox-neutral and mild reaction conditions. Moreover, these reactions feature good functional-group tolerance, broad substrate scope, easy scalability and facile product diversification. The important products could also be formed with either spirocycles or two adjacent tetrasubstituted carbon centers., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The first direct use of carbon dioxide in the lactamization of alkenyl and heteroaryl C-H bonds to synthesize important 2-quinolinones and polyheterocycles in moderate to excellent yields is reported. Carbon dioxide, a nontoxic, inexpensive, and readily available greenhouse gas, acts as an ideal carbonyl source. Importantly, this transition-metal-free and redox-neutral process is eco-friendly and desirable for the pharmaceutical industry. Moreover, these reactions feature a broad substrate scope, good functional group tolerance, facile scalability, and easy product derivatization., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)