scholarly journals Functionalization of C–H bonds in acetophenone oximes with arylacetic acids and elemental sulfur

RSC Advances ◽  
2020 ◽  
Vol 10 (19) ◽  
pp. 11024-11032 ◽  
Author(s):  
Phuc H. Pham ◽  
Khang X. Nguyen ◽  
Hoai T. B. Pham ◽  
Thien T. Tran ◽  
Tung T. Nguyen ◽  
...  
Keyword(s):  
Transition Metals ◽  
Elemental Sulfur ◽  
Arylacetic Acids ◽  
Acetophenone Oxime

Annulation of acetophenone oxime acetates, arylacetic acids or esters, and elemental sulfur in absence of transition metals is reported.

Sulfur-Mediated Decarboxylative Coupling of 2-Nitrobenzyl Alcohols and Arylacetic Acids

Synlett ◽  
2020 ◽  
Vol 31 (11) ◽  
pp. 1112-1116
Author(s):  
Tung T. Nguyen ◽  
Nam T. S. Phan ◽  
Khang X. Nguyen ◽  
Duyen K. Nguyen ◽  
Phuc H. Pham ◽  
...  
Keyword(s):  
Transition Metals ◽  
Nitrogen Source ◽  
Elemental Sulfur ◽  
New Method ◽  
Complex Structures ◽  
Reaction Conditions ◽  
Mild Conditions ◽  
Decarboxylative Coupling ◽  
Arylacetic Acids

We report a new method for the synthesis of substituted quinazolines by the condensation of 2-nitrobenzyl alcohols with arylacetic acids. The transformation requires the use of urea as a nitrogen source, elemental sulfur as a promoter, DABCO as a base, and DMSO as a solvent. Functionalities such as chloro, fluoro, trifluoromethyl, thienyl, and indolyl groups were all compatible with the reaction conditions. Because our method uses stable simple substrates to obtain the N,N-heterocycles in the absence of transition metals, it offers a potential pathway for preparing complex structures under mild conditions.

Elemental sulfur mediated synthesis of pyrrolo[1,2-α]quinoxalines from 1-(2-nitroaryl) pyrroles

Synthesis ◽  
2021 ◽  
Author(s):  
Tung Nguyen ◽  
Tuan Ho ◽  
Nam T. S. Phan ◽  
Nhu Phan ◽  
Thuyen Ho ◽  
...  
Keyword(s):  
Transition Metals ◽  
Elemental Sulfur ◽  
Coupling Reagents ◽  
Benzyl Alcohols ◽  
Fused Heterocycles ◽  
Arylacetic Acids ◽  
Harsh Conditions

Methods to afford pyrrolo[1,2-α]quinoxalines often require the use of prefunctionalized aniline precursors, transition metals, and/or harsh conditions. Herein we describe a simple coupling of 1-(2-nitroaryl)pyrroles and arylacetic acids, in the presence of elemental sulfur, to furnish the fused heterocycles in good yields. The conditions were compatible with many functionalities including ester, nitrile, halogen, and nitro groups. Use of benzyl alcohols and picoline coupling reagents was also attempted.

Elemental Sulfur Mediated Decarboxylative Redox Cyclization Reaction of o-Chloronitroarenes and Arylacetic Acids

2015 ◽  
Vol 17 (4) ◽  
pp. 976-978 ◽  
Author(s):  
Tirumaleswararao Guntreddi ◽  
Rajeshwer Vanjari ◽  
Krishna Nand Singh
Keyword(s):  
Elemental Sulfur ◽  
Cyclization Reaction ◽  
Arylacetic Acids

ChemInform Abstract: Elemental Sulfur Mediated Decarboxylative Redox Cyclization Reaction of o-Chloronitroarenes and Arylacetic Acids.

ChemInform ◽  
2015 ◽  
Vol 46 (28) ◽  
pp. no-no
Author(s):  
Tirumaleswararao Guntreddi ◽  
Rajeshwer Vanjari ◽  
Krishna Nand Singh
Keyword(s):  
Elemental Sulfur ◽  
Cyclization Reaction ◽  
Arylacetic Acids

Synthesis of 2-Arylbenzothiazol-5-amines from N,N-Dialkyl-3-nitroanilines

Synlett ◽  
2020 ◽  
Vol 31 (18) ◽  
pp. 1813-1816 ◽  
Author(s):  
Tung T. Nguyen ◽  
Nam T. S. Phan ◽  
Hang T. Pham ◽  
Tuan H. Ho ◽  
Duy Q. Do ◽  
...  
Keyword(s):  
Elemental Sulfur ◽  
Reaction Conditions ◽  
Simple Method ◽  
Simple Route ◽  
Arylacetic Acids ◽  
Derivatives Of

AbstractWe report a simple method for coupling of N,N-dialkyl-3-nitroarenes, elemental sulfur, and activated sp3 C–H bonds in 2-methylazaarenes or arylacetic acids to afford derivatives of 2-arylbenzothiazol-5-amines. Only DABCO base was required, and many heterocycles such as imidazoles, oxazoles, quinolines, and thiophenes were compatible with the reaction conditions. Our approach offers a simple route to useful substituted thiazol-5-amines from commercially available nitroarenes.

Elemental Sulfur-Mediated Decarboxylative Redox Cyclization ­Reaction: Copper-Catalyzed Synthesis of 2-Substituted Benzo­thiazoles

Synlett ◽  
2017 ◽  
Vol 29 (02) ◽  
pp. 219-224 ◽  
Author(s):  
Xin Wang ◽  
Xiaotong Li ◽  
Renhe Hu ◽  
Zhao Yang ◽  
Ren Gu ◽  
...  
Keyword(s):  
Functional Groups ◽  
Elemental Sulfur ◽  
Antitumor Drug ◽  
Cyclization Reaction ◽  
Copper Metal ◽  
Wide Range ◽  
Ligand Free ◽  
Arylacetic Acids ◽  
Scale Experiment

A S8-mediated directed decarboxylative redox-cyclization strategy for the synthesis of 2-substituted benzothiazoles from o-iodoanilines, arylacetic acids, and elemental sulfur catalyzed by cheap copper metal has been developed. This reaction is operationally simple, ligand-free, compatible with a wide range of functional groups, and provides the desired products in good to excellent yields. In addition, a gram-scale experiment was carried out to furnish PMX 610, an antitumor drug.

NH4I-promoted oxidative formation of benzothiazoles and thiazoles from arylacetic acids and phenylalanines with elemental sulfur

2021 ◽  
Author(s):  
Yujia Xia ◽  
Huawen Huang ◽  
Wei Hu ◽  
Guo-Jun Deng
Keyword(s):  
Catalytic System ◽  
Elemental Sulfur ◽  
Three Component Reaction ◽  
Arylacetic Acids

A NH4I/K3PO4-based catalytic system has been established to enable oxidative formation of thiazole compounds from arylacetic acids and phenylalanines with elemental sulfur. While the three-component reaction of anilines or β-naphthylamines...

Precipitation in silicon: Microanalysis

1988 ◽  
Vol 46 ◽  
pp. 474-475
Author(s):  
R.W. Carpenter
Keyword(s):  
Transition Metals ◽  
Spatial Resolution ◽  
Thin Foil ◽  
Precipitation Reaction ◽  
High Current ◽  
Reaction Products ◽  
Carbon And Nitrogen ◽  
Dielectric Layers ◽  
Precipitation Processes ◽  
Areas Of Interest

Interest in precipitation processes in silicon appears to be centered on transition metals (for intrinsic and extrinsic gettering), and oxygen and carbon in thermally aged materials, and on oxygen, carbon, and nitrogen in ion implanted materials to form buried dielectric layers. A steadily increasing number of applications of microanalysis to these problems are appearing. but still far less than the number of imaging/diffraction investigations. Microanalysis applications appear to be paced by instrumentation development. The precipitation reaction products are small and the presence of carbon is often an important consideration. Small high current probes are important and cryogenic specimen holders are required for consistent suppression of contamination buildup on specimen areas of interest. Focussed probes useful for microanalysis should be in the range of 0.1 to 1nA, and estimates of spatial resolution to be expected for thin foil specimens can be made from the curves shown in Fig. 1.

Scanning Electron Microscope Study of Bacteria on Mineral Surfaces

1976 ◽  
Vol 34 ◽  
pp. 130-131
Author(s):  
V.K. Berry
Keyword(s):  
Oxidation Reaction ◽  
Electron Microscope Study ◽  
Elemental Sulfur ◽  
Thiobacillus Ferrooxidans ◽  
Physical Contact ◽  
Metal Sulfides ◽  
Low Grade ◽  
Mineral Surfaces ◽  
Mineral Surface ◽  
Scanning Electron Microscope Study

There are two strains of bacteria viz. Thiobacillus thiooxidansand Thiobacillus ferrooxidanswidely mentioned to play an important role in the leaching process of low-grade ores. Another strain used in this study is a thermophile and is designated Caldariella .These microorganisms are acidophilic chemosynthetic aerobic autotrophs and are capable of oxidizing many metal sulfides and elemental sulfur to sulfates and Fe2+ to Fe3+. The necessity of physical contact or attachment by bacteria to mineral surfaces during oxidation reaction has not been fairly established so far. Temple and Koehler reported that during oxidation of marcasite T. thiooxidanswere found concentrated on mineral surface. Schaeffer, et al. demonstrated that physical contact or attachment is essential for oxidation of sulfur.

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