Mechanochemical indole synthesis by rhodium-catalysed oxidative coupling of acetanilides and alkynes under solventless conditions in a ball mill

2017 ◽  
Vol 19 (11) ◽  
pp. 2520-2523 ◽  
Author(s):  
Gary N. Hermann ◽  
Celine L. Jung ◽  
Carsten Bolm
Keyword(s):  
Oxidative Coupling ◽  
Ball Mill ◽  
Planetary Mill ◽  
Indole Synthesis

Indoles are prepared by rhodium(iii)-catalysed C–H bond functionalisation under mechanochemical conditions in a planetary mill.

scholarly journals Effect of Milling Parameters on the Development of a Nanostructured FCC–TiNb15Mn Alloy via High-Energy Ball Milling

Metals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1225
Author(s):  
Cristina García-Garrido ◽  
Ranier Sepúlveda Sepúlveda Ferrer ◽  
Christopher Salvo ◽  
Lucía García-Domínguez ◽  
Luis Pérez-Pozo ◽  
...  
Keyword(s):  
Mechanical Alloying ◽  
Ball Mill ◽  
Milling Time ◽  
High Energy ◽  
Planetary Mill ◽  
Nominal Composition ◽  
Mechanically Alloyed ◽  
Milling Parameters ◽  
Energy Ball ◽  
Full Conversion

In this work, a blend of Ti, Nb, and Mn powders, with a nominal composition of 15 wt.% of Mn, and balanced Ti and Nb wt.%, was selected to be mechanically alloyed by the following two alternative high-energy milling devices: a vibratory 8000D mixer/mill® and a PM400 Retsch® planetary ball mill. Two ball-to-powder ratio (BPR) conditions (10:1 and 20:1) were applied, to study the evolution of the synthesized phases under each of the two mechanical alloying conditions. The main findings observed include the following: (1) the sequence conversion evolved from raw elements to a transitory bcc-TiNbMn alloy, and subsequently to an fcc-TiNb15Mn alloy, independent of the milling conditions; (2) the total full conversion to the fcc-TiNb15Mn alloy was only reached by the planetary mill at a minimum of 12 h of milling time, for either of the BPR employed; (3) the planetary mill produced a non-negligible Fe contamination from the milling media, when the highest BPR and milling time were applied; and (4) the final fcc-TiNb15Mn alloy synthesized presents a nanocrystalline nature and a partial degree of amorphization.

ChemInform Abstract: Indole Synthesis via Cobalt(III)-Catalyzed Oxidative Coupling of N-Arylureas and Internal Alkynes.

ChemInform ◽  
2016 ◽  
Vol 47 (33) ◽  
Author(s):  
Zhuo-Zhuo Zhang ◽  
Bin Liu ◽  
Jing-Wen Xu ◽  
Sheng-Yi Yan ◽  
Bing-Feng Shi
Keyword(s):  
Oxidative Coupling ◽  
Internal Alkynes ◽  
Indole Synthesis

scholarly journals Convenient Synthesis of 6,7,12,13-Tetrahydro-5H-Cyclohepta[2,1-b:3,4-b’]diindole Derivatives Mediated by Hypervalent Iodine (III) Reagent

Molecules ◽  
2019 ◽  
Vol 24 (5) ◽  
pp. 960 ◽  
Author(s):  
Lei Peng ◽  
Xiaofei Zhang ◽  
Chunhao Yang
Keyword(s):  
Oxidative Coupling ◽  
Biological Activities ◽  
Condensation Reaction ◽  
Large Family ◽  
Membered Ring ◽  
Hypervalent Iodine ◽  
Fischer Indole Synthesis ◽  
Convenient Synthesis ◽  
First Time ◽  
Indole Synthesis

Bisindolyl alkaloids represent a large family of natural and synthetic products that display various biological activities. Among the bisindole compounds, 6,7,12,13-tetrahydro-5H-cyclohepta[2,1-b:3,4-b’]diindoles have received little attention. Only two methods have been developed for the construction of the 6,7,12,13-tetrahydro-5H-cyclohepta[2,1-b:3,4-b’]diindole scaffold thus far, including the classical Fischer indole synthesis conducted by reacting indole-fused cycloheptanone and hydrazines, and the condensation reaction to build the seven-membered ring. Here, we report for the first time a new route to synthesize 6,7,12,13-tetrahydro-5H-cyclohepta[2,1-b:3,4-b’]diindoles through intramolecular oxidative coupling of 1,3-di(1H-indol-3-yl)propanes in the presence of PIFA, DDQ and TMSCl with moderate to excellent yields.

Mutual transformation between crystalline phases in silicon after treatment in a planetary mill: HRTEM studies

2016 ◽  
Vol 72 (5) ◽  
pp. 733-737 ◽  
Author(s):  
Boris Kulnitskiy ◽  
Mikhail Annenkov ◽  
Igor Perezhogin ◽  
Mikhail Popov ◽  
Danila Ovsyannikov ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Ball Mill ◽  
Initial Phase ◽  
Stacking Faults ◽  
Planetary Mill ◽  
Mutual Transformation ◽  
Transmission Electron ◽  
Mechanisms Of Formation ◽  
Temperature And Pressure

High-resolution transmission electron microscopy (HRTEM) studies of silicon after treatment in a planetary mill have been performed. It is shown that along with the initial phase of silicon, Si-I, the sample also contains some high-pressure phases: Si-III (Kasper phase) and Si-IV (lonsdaleite). We studied the orientation relationship between the particles of different phases, finding that there are, in general, two mechanisms of formation of Si-IV: (1) through the stacking faults formation; (2) through the transformation first to the Kasper phase (Si-III), and then from the Kasper phase to Si-IV. Estimations of temperature and pressure conditions in the planetary ball mill made previously are in accordance with the conditions of formation of the above-mentioned phases.

Indole Synthesis via Cobalt(III)-Catalyzed Oxidative Coupling of N-Arylureas and Internal Alkynes

2016 ◽  
Vol 18 (8) ◽  
pp. 1776-1779 ◽  
Author(s):  
Zhuo-Zhuo Zhang ◽  
Bin Liu ◽  
Jing-Wen Xu ◽  
Sheng-Yi Yan ◽  
Bing-Feng Shi
Keyword(s):  
Oxidative Coupling ◽  
Internal Alkynes ◽  
Indole Synthesis

ChemInform Abstract: Indole Synthesis via Rhodium-Catalyzed Oxidative Coupling of Acetanilides and Internal Alkynes.

ChemInform ◽  
2009 ◽  
Vol 40 (18) ◽  
Author(s):  
David R. Stuart ◽  
Megan Bertrand-Laperle ◽  
Kevin M. N. Burgess ◽  
Keith Fagnou
Keyword(s):  
Oxidative Coupling ◽  
Internal Alkynes ◽  
Indole Synthesis

Grinding of Agglomerate AlN Powder by Wet Milling

2006 ◽  
Vol 317-318 ◽  
pp. 45-48
Author(s):  
Jin Yu Qiu ◽  
Koji Watari ◽  
Yuji Hotta ◽  
Yoshiaki Kinemuchi ◽  
Kenshi Mitsuishi
Keyword(s):  
Thermal Conductivity ◽  
Low Temperature ◽  
Ball Mill ◽  
Planetary Mill ◽  
Size Reduction ◽  
Low Temperature Sintering ◽  
Wet Milling ◽  
Fine Grinding ◽  
Better Than ◽  
Grinding Mill

Fine AlN powder doped with Y2O3 and CaO as sintering additives was ground by a ball mill, a planetary ball mill and a super-fine grinding mill in order to obtain fine homogenous powder for low-temperature sintering. The size reduction and the sinterability of ground powders at 1500oC for 6 h were investigated. The size and shape of the agglomeration showed no significant change after the ball mill and planetary mill processes, resulting in poor densification. On the contrary, AlN particles with size of 50~100 nm was pulverized and dispersed by a super-fine grinding mill with very small ZrO2 beads as a mill media. The microstructures of the specimen exhibited equiaxed and homogenous grains with size of 0.3~0.4 μm. Pores in the specimens were eliminated. The thermal conductivity was 70W/mK, which is better than that of Al2O3 ceramics (~20W/mK).

scholarly journals Indole Synthesis via Rhodium Catalyzed Oxidative Coupling of Acetanilides and Internal Alkynes

2008 ◽  
Vol 130 (49) ◽  
pp. 16474-16475 ◽  
Author(s):  
David R. Stuart ◽  
Mégan Bertrand-Laperle ◽  
Kevin M. N. Burgess ◽  
Keith Fagnou
Keyword(s):  
Oxidative Coupling ◽  
Internal Alkynes ◽  
Indole Synthesis

scholarly journals Indole Synthesis via Rhodium Catalyzed Oxidative Coupling of Acetanilides and Internal Alkynes

2010 ◽  
Vol 132 (50) ◽  
pp. 17973-17973
Author(s):  
David R. Stuart ◽  
Mégan Bertrand-Laperle ◽  
Kevin M. N. Burgess ◽  
Keith Fagnou
Keyword(s):  
Oxidative Coupling ◽  
Internal Alkynes ◽  
Indole Synthesis

Effect of Sintering Temperature on the Dielectric Properties of Pb(Zr0.52Ti0.48)O3 Ceramics Synthesized via High Planetary Ball Mill

2015 ◽  
Vol 1087 ◽  
pp. 167-171
Author(s):  
Mohd Fariz Ab Rahman ◽  
Asyraf bin Arshad ◽  
Zainal Arifin Ahmad ◽  
Julie Juliewatty Mohamed
Keyword(s):  
Dielectric Properties ◽  
Ball Mill ◽  
Sintering Temperature ◽  
Raw Materials ◽  
Perovskite Phase ◽  
Secondary Phase ◽  
Planetary Mill ◽  
Dielectric Constants ◽  
Planetary Ball Mill ◽  
Increasing Temperature

The properties of Pb(Zr0.52Ti0.48)O3(PZT) ceramics have been studied. PZT ceramic powders were successfully prepared by high planetary ball mill method under different milling time and then were sintered at different sintering temperature. The raw materials of PbO, ZrO2 and TiO2, powders were ball milled at 40 and 60 hours using high planetary mill. The mixing powders then were compacted and sintered at 950°C and 1200°C. Formations of the perovskite phase along with some secondary phase were seen after 40 and 60 hours of milling while single phase formation of PZT was seen after sintered at both sintering temperatures. The grain size of the samples becomes larger with the increasing temperature. In dielectric properties analysis, the dielectric constants were reduced due to increasing sintering temperature. Meanwhile, the loss tangents increased with sintering temperature.

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