Direct Preparation of Mesophase Pitch from Naphthalene by the Aid of HF/BF3

1989 ◽  
Vol 18 (11) ◽  
pp. 1893-1896 ◽  
Author(s):  
Isao Mochida ◽  
Kiyoyuki Shimizu ◽  
Yozo Korai ◽  
Yukio Sakai ◽  
Susumu Fujiyama
Keyword(s):  
Mesophase Pitch ◽  
Direct Preparation

A Mild and Simple Method for Making MIDA Boronates

2020 ◽  
Author(s):  
Aidan Kelly ◽  
Peng-Jui (Ruby) Chen ◽  
Jenna Klubnick ◽  
Daniel J. Blair ◽  
Martin D. Burke
Keyword(s):  
Organic Synthesis ◽  
Boronic Acids ◽  
Simple Method ◽  
Direct Preparation ◽  
Synthesis Procedure ◽  
Harsh Conditions

<div> <div> <div> <p>Existing methods for making MIDA boronates require harsh conditions and complex procedures to achieve dehydration. Here we disclose that a pre-dried form of MIDA, MIDA anhydride, acts as both a source of the MIDA ligand and an in situ desiccant to enable a mild and simple MIDA boronate synthesis procedure. This method expands the range of sensitive boronic acids that can be converted into their MIDA boronate counterparts. Further utilizing unique properties of MIDA boronates, we have developed a MIDA Boronate Maker Kit which enables the direct preparation and purification of MIDA boronates from boronic acids using only heating and centrifuge equipment that is widely available in labs that do not specialize in organic synthesis. </p> </div> </div> </div>

Effect of Pre-oxidation on the Pore Structure and Foaming Mechanisms of Mesophase Pitch Based Carbon Foam

2009 ◽  
Vol 24 (2) ◽  
pp. 315-319
Author(s):  
Juan LI ◽  
Can WANG ◽  
Liang ZHAN ◽  
Rui ZHANG ◽  
Wen-Ming QIAO ◽  
...  
Keyword(s):  
Pore Structure ◽  
Carbon Foam ◽  
Mesophase Pitch

α-Ketophosphonates in the Synthesis of α-iminophosphonates

2020 ◽  
Vol 7 (2) ◽  
pp. 226-238
Author(s):  
Petro P. Ony`sko ◽  
Tetyana I. Chudakova ◽  
Vladimir V. Pirozhenko ◽  
Alexandr B. Rozhenko
Keyword(s):  
Bond Cleavage ◽  
Direct Synthesis ◽  
Equilibrium Mixture ◽  
Primary Amines ◽  
Alkyl Amines ◽  
Protic Solvents ◽  
Metallic Salts ◽  
Direct Preparation ◽  
Stage Synthesis ◽  
Aprotic Dipolar Solvent

The potentialities of condensation of α-ketophosphonates with primary amines for direct synthesis of α-iminophosphonates have been revealed. Diesters of α-ketophosphonic acids react with the primary amines by two competitive pathways: with a formation of α-iminophosphonates or a C-P bond cleavage resulting in a hydrogen phosphonate and an acylated amine. In many cases, the latter undesirable pathway is dominant, especially for more nucleophilic alkyl amines. Using metallic salts of α-ketophosphonates avoids the C-P bond cleavage, allowing direct preparation of α-phosphorylated imines by the reaction with primary amines. This strategy provides an atom economy single-stage synthesis of iminophosphonates – precursors of bio relevant phosphorus analogs of α-amino acids. Methyl sodium iminophosphonates, bearing aryl or heteryl substituents at the imino carbon atom exist in solutions at room temperature as an equilibrium mixture of Z- and E-isomers. A configuration of the C=N bond can be controlled by the solvent: changing the aprotic dipolar solvent DMSO-d6 by water or alcohols leads to the change from a predominant Z-isomer to almost an exclusive E-form. In contrast, diesters of the respective iminophosphonates exist in non-protic solvents predominantly in Econfiguration. The solvent effect on E-Z stereochemistry is demonstrated by DFT calculations.

Preparation of mesophase pitch based mesoporous carbons using an imprinting method

Carbon ◽  
2007 ◽  
Vol 45 (15) ◽  
pp. 1
Author(s):  
Ying Liu ◽  
liang Zhan ◽  
Rui Zhang ◽  
Wen-ming Qiao ◽  
Xiao-yi Liang ◽  
...  
Keyword(s):  
Mesophase Pitch ◽  
Mesoporous Carbons

Preparation of mesophase pitch from refined coal tar pitch using naphthalene-based mesophase pitch as nucleating agent

Fuel ◽  
2019 ◽  
Vol 243 ◽  
pp. 390-397 ◽  
Author(s):  
Xingwei Zhang ◽  
Yuchen Meng ◽  
Baolin Fan ◽  
Zhaokun Ma ◽  
Huaihe Song
Keyword(s):  
Coal Tar ◽  
Nucleating Agent ◽  
Coal Tar Pitch ◽  
Mesophase Pitch

Direct preparation of polyfunctional amino-substituted arylmagnesium reagents via an iodine–magnesium exchange reaction

2003 ◽  
pp. 396-397 ◽  
Author(s):  
Greta Varchi ◽  
Christiane Kofink ◽  
David M. Lindsay ◽  
Alfredo Ricci ◽  
Paul Knochel
Keyword(s):  
Exchange Reaction ◽  
Direct Preparation ◽  
Magnesium Exchange
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