Formation of amides, their intramolecular reactions for the synthesis of N-heterocycles, and preparation of a marketed drug, sildenafil: a comprehensive coverage

Laha, Joydev K.; Patel, Kinjal; Tummalapalli, K. S. Satyanarayana; Dayal, Neetu

doi:10.1039/c6cc04259g

Cited by 60 publications

(25 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…(Scheme 77). [353] When the ortho ‐position of anilines initially bears a nucleophilic group, such as NH 2 , OH, SH, CONH 2 , or COOH, the resulting amides undergo a cyclization, providing access to diverse five‐ and six‐membered azaheterocycles. Its synthetic utility was demonstrated by the synthesis of Sildenafil (Viagra TM ) (Scheme 77B).…”

Section: Decarboxylative C−pnictogen Bond Formationmentioning

confidence: 99%

Decarboxylation‐Initiated Intermolecular Carbon‐Heteroatom Bond Formation

Zeng¹,

Feceu

Sivendran

et al. 2021

Adv Synth Catal

View full text Add to dashboard Cite

Carboxylic acids are among the most used feedstock chemicals due to their great structural diversity and easy handling. The use of carboxylic acids and their derivatives in decarboxylative couplings has proven to be a valuable tool for the construction of C−C and C‐heteroatom bonds. This synthetic strategy provides a complementary bond disconnection to traditional cross‐coupling methods. In this review, we provide a comprehensive overview of decarboxylation‐initiated intermolecular C‐heteroatom bond formation, outlining several main mechanistic concepts combined with early examples and highlighting the achievements made in the past decade until January 2021. In these reactions, carboxylic acids and their derivatives undergo initial decarboxylation and then react with other heteroatom electrophiles and nucleophiles, thus replacing the carboxylate group with a valuable and prevalent heteroatom functionality.

show abstract

Section: Decarboxylative C−pnictogen Bond Formationmentioning

confidence: 99%

Decarboxylation‐Initiated Intermolecular Carbon‐Heteroatom Bond Formation

Zeng¹,

Feceu

Sivendran

et al. 2021

Adv Synth Catal

View full text Add to dashboard Cite

show abstract

“…Our study commenced with the reaction of N , N -diethylbenzamide 1a and phenylglyoxylic acid 2a in the presence of a palladium-catalyst and oxidant (Table 1). Previously, we 9,10 and others 11 demonstrated that an acyl radical could be generated efficiently from 2a in the presence of a persulfate reagent under thermal conditions. A judicious choice of oxidant could serve both purposes.…”

Section: Resultsmentioning

confidence: 93%

Palladium-Catalyzed Decarboxylative Ortho-Acylation of Tertiary Benzamides with Arylglyoxylic Acids

2017

Self Cite

View full text Add to dashboard Cite

A palladium-catalyzed ortho-acylation of tertiary benzamides using arylglyoxylic acids has been described. Unlike the palladium insertion reported to occur in the distorted N–C(O) amide bond of tertiary benzamides, the current study unveils ortho C–H palladation in acylic or cyclic N , N -dialkylbenzamides affording ortho-acylated tertiary benzamides in good to excellent yields. Our experimental study on the mechanism provides information on the tendency of the amide nitrogen toward weak coordination with palladium as opposed to oxygen. However, density functional theory calculations suggest coordination of amide oxygen to palladium, which makes the mechanism especially interesting. A Pd(II)/Pd(III) catalytic cycle and nucleophilic attack by the acyl radical rather than arylglyoxylate anion are supported by mechanistic studies.

show abstract

“…[211,212] In literature, the synthesis of benzothiazoles has been explored in the presence of transition metals or strong oxidants under high temperature. [211,212] In 2020, Sharma et al reported a metal-/photocatalyst-free visible light-induced decarboxylative cross-coupling of α-keto acids and 2-aminothiophenols for the construction of benzothiazoles under mild reaction conditions (Scheme 72). [213] Different substituted 2-aminothiophenols reacted with various α-keto acids in the optimal conditions to provide corresponding benzothia-zoles in moderate to good yields.…”

Section: Radical Cyclizations Through Sulphur-centered Radicalsmentioning

confidence: 99%

“…Benzothiazoles are ubiquitous molecules in natural and synthetic heterocycles [211,212] . In literature, the synthesis of benzothiazoles has been explored in the presence of transition metals or strong oxidants under high temperature [211,212] .…”

Section: Photoinduced Radical Cascade Cyclizations Promoted By Eda Complexesmentioning

confidence: 99%

Progress in Photoinduced Radical Reactions using Electron Donor‐Acceptor Complexes

et al. 2021

View full text Add to dashboard Cite

Photocatalyzed organic synthesis transformation is a remarkable green synthetic strategy because of the advantages of operational simplicity, high chemoselectivities, cheap, and environmental benignancy, along with the extensive applications in the fields of organic, pharmaceutical and functional material chemistry. Generally, photoredox catalysts or photosensitizers are necessary for the generation of their excited states to perform the successive oxidative or reductive reactions through the single electron transfer (SET) or energy transfer (ET) process. Furthermore, the exploration of a colored electron donor-acceptor (EDA) complex or a charge transfer (CT) complex between an electron-rich and an electron-poor substrate provides the chance to deliver the excited intermediate under the irradiation of light, resulting in the formation of radical activate species through a single electron transfer to induce successive various radical reactions. These reactions were performed without the need of any external photocatalysts under mild reaction conditions. Herein, this review focuses on the recent progress on photoinduced radical addition reactions, radical borylations, reductive reactions, radical-radical cross-coupling reactions, degradation reactions and radical cascade cyclization via EDA complexes. We highlight these novel green synthetic methodologies and applications, as well as the mechanisms. This review will help to provide references for organic and medicinal chemists who are charmed by these green organic photochemical transformations based on EDA complexes.

show abstract

Formation of amides, their intramolecular reactions for the synthesis of N-heterocycles, and preparation of a marketed drug, sildenafil: a comprehensive coverage

Cited by 60 publications

References 32 publications

Decarboxylation‐Initiated Intermolecular Carbon‐Heteroatom Bond Formation

Decarboxylation‐Initiated Intermolecular Carbon‐Heteroatom Bond Formation

Palladium-Catalyzed Decarboxylative Ortho-Acylation of Tertiary Benzamides with Arylglyoxylic Acids

Progress in Photoinduced Radical Reactions using Electron Donor‐Acceptor Complexes

Contact Info

Product

Resources

About