Facile synthesis of benzo[b]thiophenes via metal-free radical-triggered intramolecular C–S bond formation

2017 ◽  
Vol 15 (31) ◽  
pp. 6493-6499 ◽  
Author(s):  
Wei Fan ◽  
Kwong-Yuen Chen ◽  
Qi-Peng Chen ◽  
Guigen Li ◽  
Bo Jiang
Keyword(s):  
Free Radical ◽  
Bond Formation ◽  
Facile Synthesis ◽  
Metal Free

A facile method for the synthesis of benzo[b]thiophenes with good to excellent yields via metal-free intramolecular C–S bond formation has been developed by utilizing I2 as a catalyst and O2 from air as an oxidant (20 examples).

Photoinduced Oxidative Cross-Coupling for O–S Bond Formation: A Facile Synthesis of Alkyl Benzenesulfonates

Synlett ◽  
2017 ◽  
Vol 28 (13) ◽  
pp. 1558-1563 ◽  
Author(s):  
Aiwen Lei ◽  
Atul Singh ◽  
Hong Yi ◽  
Guoting Zhang ◽  
Changliang Bian ◽  
...  
Keyword(s):  
Visible Light ◽  
Bond Formation ◽  
Cross Coupling ◽  
Selective Synthesis ◽  
Mechanistic Studies ◽  
Facile Synthesis ◽  
Metal Free

We have developed a photoinduced oxidative cross-coupling of thiophenols with alcohols for O–S bond formation. The protocol uses visible light, a metal-free photocatalyst, and oxygen as the oxidant for the selective synthesis of alkyl benzenesulfonates; no ligand co-additive is necessary. Mechanistic studies suggested that the disulfide and alkyl benzenesulfinate are involved as intermediates and that the transformation proceeds by a radical pathway.

Metal-free, radical 1,6-conjugated addition of cyclic ethers with para-quinone methides (p-QMs)

2019 ◽  
Vol 17 (12) ◽  
pp. 3239-3248 ◽  
Author(s):  
Satish G. More ◽  
Gurunath Suryavanshi
Keyword(s):  
Free Radical ◽  
Efficient Method ◽  
Bond Formation ◽  
Cyclic Ethers ◽  
Quinone Methides ◽  
Metal Free

An efficient method for metal-free C–C bond formation between p-quinone methides (p-QMs) and cyclic ethers via a radical pathway to afford substituted diarylmethanes and triarylmethanes or to effect the α-alkylation of the cyclic ethers has been developed.

Efficient synthesis of 1,2-benzisothiazoles from o-haloarylamidines and elemental sulfur via N–S/C–S bond formation under transition-metal-free conditions

2018 ◽  
Vol 20 (4) ◽  
pp. 827-831 ◽  
Author(s):  
Hao Xie ◽  
Guozheng Li ◽  
Feng Zhang ◽  
Fuhong Xiao ◽  
Guo-Jun Deng
Keyword(s):  
Transition Metal ◽  
Functional Groups ◽  
Elemental Sulfur ◽  
Bond Formation ◽  
Efficient Synthesis ◽  
Facile Synthesis ◽  
Good Tolerance ◽  
Metal Free

Facile synthesis of 1,2-benzisothiazoles from amidines and elemental sulfur via N–S/C–S bond formation under transition-metal-free conditions has been developed with good tolerance of a broad range of functional groups.

Metal-free cascade construction of C–C bonds by activation of inert C(sp3)–H bonds

2015 ◽  
Vol 51 (7) ◽  
pp. 1320-1322 ◽  
Author(s):  
Honglin Zhang ◽  
Changduo Pan ◽  
Ning Jin ◽  
Zhangxi Gu ◽  
Hongwen Hu ◽  
...  
Keyword(s):  
Free Radical ◽  
Bond Formation ◽  
Radical Process ◽  
Metal Free ◽  
Catalytic Activation ◽  
Free Radical Process

Metal-free catalytic activation of inert C(sp3)–H/elimination of SO2/C–C bond formation via a free radical process were achieved in sequence.

Transition-metal-free oxidative carboazidation of acrylamides via cascade C–N and C–C bond-forming reactions

2014 ◽  
Vol 12 (25) ◽  
pp. 4329-4334 ◽  
Author(s):  
Jun Qiu ◽  
Ronghua Zhang
Keyword(s):  
Free Radical ◽  
Transition Metal ◽  
Efficient Method ◽  
Bond Formation ◽  
Cascade Process ◽  
Metal Free ◽  
Bond Forming ◽  
Bond Forming Reactions ◽  
Radical Cascade ◽  
Novel Strategy

A novel transition-metal-free oxidative carboazidation of acrylamides using inexpensive NaN3 and K2S2O8 was achieved, which not only provided an efficient method to prepare various N3-substituted oxindoles, but also represented a novel strategy for C–N and C–C bond formation via a free-radical cascade process.

Deaminative carbonylative thioesterification of activated alkylamines with thiophenols under transition-metal-free conditions

2021 ◽  
Author(s):  
Fengqian Zhao ◽  
Xiao-Feng Wu
Keyword(s):  
Free Radical ◽  
Transition Metal ◽  
Metal Free

A transition-metal-free radical carbonylation of activated alkylamines with thiophenols has been successfully developed. Various thioesters were selectively produced with moderate to good yields.

Stereodivergent Alkyne Hydrofluorination Using a Simple Practical Reagent

2020 ◽  
Author(s):  
Rui Guo ◽  
Xiaotian Qi ◽  
Hengye Xiang ◽  
Paul Geaneoates ◽  
Ruihan Wang ◽  
...  
Keyword(s):  
Bond Formation ◽  
Biologically Active ◽  
Dft Studies ◽  
Thermodynamic Control ◽  
Important Goal ◽  
Peptide Bonds ◽  
Metal Free ◽  
Vinyl Cation ◽  
E And Z Isomers ◽  
Vinyl Fluorides

Vinyl fluorides play an important role in drug development as they serve as bioisosteres for peptide bonds and are found in a range of biologically active molecules. The discovery of safe, general and practical procedures to prepare vinyl fluorides remains an important goal and challenge for synthetic chemistry. Here we introduce an inexpensive and easily-handled reagent and report simple, scalable, and metal-free protocols for the regioselective and stereodivergent hydrofluorination of alkynes to access both the E and Z isomers of vinyl fluorides. These conditions were suitable for a diverse collection of alkynes, including several highly-functionalized pharmaceutical derivatives. Mechanistic and DFT studies support C–F bond formation through a vinyl cation intermediate, with the (E)- and (Z)-hydrofluorination products forming under kinetic and thermodynamic control, respectively.<br>

Formation of Carbon-Oxygen Bond Mediated by Hypervalent Iodine Reagents Under Metal-free Conditions

2020 ◽  
Vol 17 ◽  
Author(s):  
Ayesha Jalil ◽  
Yaxin O Yang ◽  
Zhendong Chen ◽  
Rongxuan Jia ◽  
Tianhao Bi ◽  
...  
Keyword(s):  
Natural Products ◽  
Bond Formation ◽  
Building Blocks ◽  
Review Article ◽  
Hypervalent Iodine ◽  
Metal Free ◽  
Bioactive Natural Products ◽  
The Past ◽  
Oxygen Bond ◽  
Privileged Scaffolds

: Hypervalent iodine reagents are a class of non-metallic oxidants have been widely used in the construction of several sorts of bond formations. This surging interest in hypervalent iodine reagents is essentially due to their very useful oxidizing properties, combined with their benign environmental character and commercial availability from the past few decades ago. Furthermore, these hypervalent iodine reagents have been used in the construction of many significant building blocks and privileged scaffolds of bioactive natural products. The purpose of writing this review article is to explore all the transformations in which carbon-oxygen bond formation occurred by using hypervalent iodine reagents under metal-free conditions

Synthesis of Pyrrolo[1,2-a][1,6]- and [1,8]naphthyridines by Alkyne-Carbonyl Metathesis

Synthesis ◽  
2020 ◽  
Author(s):  
Peter Ehlers ◽  
Peter Langer ◽  
Marian Blanco Ponce ◽  
Silvio Parpart ◽  
Alexander Villinger ◽  
...  
Keyword(s):  
Heterocyclic Compounds ◽  
Metathesis Reaction ◽  
Synthetic Methodology ◽  
Facile Synthesis ◽  
Reaction Conditions ◽  
One Pot ◽  
Metal Free ◽  
Modular Synthesis

AbstractA concise and modular synthesis of pyrrolo[1,2-a][1,6]- and [1,8]naphthyridines by a one-pot two-step reaction consisting of electrophilic acylation followed by an alkyne-carbonyl-metathesis reaction as the final cyclization step is reported. This developed synthetic methodology allows the facile synthesis of these heterocyclic core structures in mainly high overall yields under metal-free conditions. Reaction conditions are carefully optimized and display a novel supplement to access these tricyclic heterocyclic compounds.

Sign in / Sign up

Export Citation Format

Share Document