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Here we report a general C(sp 3 )-H/C(sp 3 )-H dehydrogenative coupling strategy for the preparation of various natural or unnatural amino acids from readily available glycine derivatives and hydrocarbons through a combination of SET and HAT process.

A catalytic α-sp(3) C-H oxidation of peptides and glycine amides was achieved under radical cation salt catalysis in the presence of O2, producing a series of substituted quinolines. The scope of this reaction shows good functional group tolerance and high efficiency of the oxidative functionalization.

Here we report a visible-light facilitated radical addition strategy for the preparation of various natural or unnatural α-amino acids from readily available glycine derivatives and alkenes. A key aspect in achieving this side carbon chain introduction reaction, while circumventing the well-documented cyclization pathway, was the employment of a radical-polar crossover strategy under redox neutral conditions. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: An oxidative tandem (4+2)‐cyclization/aromatization of N‐aryl glycine derivatives with electron‐deficient alkenes was first achieved using Ru(bpy)3Cl2 as a photocatalyst and TBHP as an oxidant in combination with visible‐light irradiation by blue LEDs. One‐electron oxidation and the following α‐deprotonation of glycine derivatives afford α‐amino alkyl radicals, which were then trapped by electrophilic maleimides. As an atom‐economic and efficient method, a variety of pyrrolo[3,4‐c]quinoline‐1,3‐diones have been obtained in good yields under mild reaction conditions. [ABSTRACT FROM AUTHOR]

We report a catalytic oxidative C–H cyanation of glycine derivatives using a simple copper(I) catalyst with NFSI as an oxidant via a radical process to furnish α-cyano glycine derivatives, which are useful intermediates for organic synthesis. CuCl acted as both a one-electron reductant and a transition-metal catalyst in this transformation. NFSI served as a one-electron oxidant and generated a N-centered radical as a H-abstractor. The reaction displayed broad substrate scope and mild reaction conditions. [ABSTRACT FROM AUTHOR]

A visible-light-mediated aerobic α-alkylation reaction of glycine derivatives with alkyl boronic acids has been established in the presence of a Ru/Cu catalyst system, giving the desired radical coupling products efficiently. The transformation features mild reaction conditions and broad substrate scope, delivering a wide range of complex unnatural α-amino-acid derivatives. [ABSTRACT FROM AUTHOR]

The auto‐oxidative Povarov/aromatization tandem reaction of N‐aryl glycine derivatives with enamides yields a series of complex quinoline derivatives in good yields. The reactions are performed using only catalytic amount of Brønsted acid and O2. The acylamino group is used as both activating and leaving group to improve the reaction efficiency in this transformation. [ABSTRACT FROM AUTHOR]

A copper‐catalyzed aerobic oxidative dehydrogenative reaction of glycine derivatives with α′‐angelicalactone is achieved under mild and simple reaction conditions. This strategy can be applicable to a wide range of gylcine esters, including complex substrates derived from (+)‐dehydroisoandrosterone or menthol, thus enabling the oxidative dehydrogenative ring‐opening reaction for producing diverse functionalized α‐amino‐γ‐ketopimelate derivatives in an atom‐economic manner. [ABSTRACT FROM AUTHOR]

An oxygenation approach to isatins via an auto‐oxidation/intramolecular annulation tandem reaction of glycine derivatives is described. This transformation provides a metal‐free protocol for the preparation of isatin derivatives, which are important structural motifs widely found in organic molecules with various functions and privileged units for the synthesis of complex heterocycles. The reaction proceeds smoothly under mild reaction conditions and requires only Brønsted acid and oxygen. Oxygen mask: An oxygenation approach to isatins via an auto‐oxidation/intramolecular annulation tandem reaction of glycine derivatives is described. This transformation provides a metal‐free protocol for the preparation of isatin derivatives, which are important structural motifs widely found in organic molecules with various functions and privileged units for the synthesis of complex heterocycles. The reaction proceeds smoothly under mild reaction conditions and requires only a Brønsted acid and oxygen. [ABSTRACT FROM AUTHOR]

The first carbon tetrabromide-promoted novel double-oxidative dehydrogenative cyclization/acidic ring opening/aromatization tandem reaction of glycine derivatives with dioxane for the synthesis of complex quinoline motifs has been developed (up to 71% yield). The use of very inexpensive substrates (glycine derivatives and dioxane) and an extremely simple metal-free promoter (carbon tetrabromide) with green molecular oxygen (air) as an oxidant make this protocol very attractive for potential synthetic applications. A plausible mechanism involving a radical process is proposed. [ABSTRACT FROM AUTHOR]

A novel CBr4-mediated dehydrogenative Povarov/aromatization tandem reaction of glycine derivatives with alkenes, leading to complex quinoline derivatives, and a CBr4-mediated dehydrogenative CH functionalization of N-aryl tetrahydroisoquinolines with nucleophiles to form CC and CP bonds are reported. The reactions were performed under very simple and mild reaction conditions; only CBr4 was used as a promoter. A plausible mechanism involving a radical process is proposed. [ABSTRACT FROM AUTHOR]

The unprecedented title reaction between glycine derivatives and indoles, as well as the auto-oxidative Povarov/ aromatization tandem reaction of glycine derivatives with olefins are described. The reactions were performed in the absence of redox-active catalysts and chemical oxidants under mild reaction conditions. Only simple organic solvents and air (or O2) were required. [ABSTRACT FROM AUTHOR]

Catalytic cerium(IV)-triggered sp3 CH bond oxidation of glycine derivatives was achieved in the presence of catalytic tris(4-bromophenyl)amine, producing a series of quinolines, in which the generation of a triarylamine radical cation is the key step to prompt the aerobic oxidation. Both intermolecular and intramolecular reactions occur smoothly, showing good generality towards the synthesis of functionalized quinoline derivatives. [ABSTRACT FROM AUTHOR]

A fragment-reassembly strategy was applied to the construction of 1,4-dihydropyridines and phosphorus-substituted 1,4-dihydropyridines under catalytic radical cation salt-induced C( sp)3H functionalization of glycine derivatives. Mechanistic studies show that domino C(sp)3H bond oxidation and CN bond cleavage reactions are involved. [ABSTRACT FROM AUTHOR]

A simple and efficient copper(I) chloride-catalyzed aerobic oxidative coupling of glycine derivatives (glycine esters, glycine amides and short peptides) with indoles has been developed. The reaction is performed in the absence of any other additives under mild conditions and only requires simple copper salts as a catalyst and oxygen as a co-oxidant. [ABSTRACT FROM AUTHOR]

A novel and efficient stable radical cation triarylaminium salt-catalyzed aerobic double Friedel-Crafts alkylation reaction of glycine derivatives with indoles has been developed. The reaction was performed in the absence of any other additives under mild conditions and only requires an air atmosphere (or oxygen, 1 atm) as co-oxidant. [ABSTRACT FROM AUTHOR]

Complex quinoline motifs are obtained by a novel CBr4-promoted double-oxidative dehydrogenative cyclization/acidic ring opening/aromatization tandem reaction of N-arylated glycine derivatives with dioxane. [ABSTRACT FROM AUTHOR]

A simple and efficient aerobic oxidative process for the synthesis of quinoline-fused lactones and lactames is described. [ABSTRACT FROM AUTHOR]

Various N-aryl glycine derivatives react in a scalable manner with tetrahydrofuran or methyl-substituted derivatives thereof to form complex quinoline fused lactone derivatives in moderate yields. [ABSTRACT FROM AUTHOR]

The reaction of glycine derivatives with indoles under O2 atmosphere gives C-arylated indol-3-yl derivatives regioselectively. [ABSTRACT FROM AUTHOR]

Aerobic oxidation of glycine derivatives in the presence of an in situ generated triarylamine radical cation followed by reaction with styrene derivatives affords a wide variety of functionalized quinolines. [ABSTRACT FROM AUTHOR]