Lithium Dicyclohexylamide - Practical and Economic Lithiations of Functionalised Arenes and Heteroarenes in Flow

The economic amide base lithium dicyclohexylamide (Cy₂NLi) allows fast and convenient (40s, 0°C) in situ trapping flow metalations of a broad range of functionalized arenes, heteroarenes and acrylate derivatives in the presence of various metal salts (ZnCl₂·2LiCl, MgCl₂, LaCl₃·2LiCl).

The resulting Zn-, Mg- or La-organometallic intermediates are trapped with various electrophiles in high yields.

These flow metalations are easily scaled-up without further optimization.

 Lithium Dicyclohexylamide - Practical and Economic Lithiations of Functionalised Arenes and Heteroarenes in Flow

M. R. Becker, M. A. Ganiek amd P. Knochel, Chem. Sci., 2015, 6, 6649

Practical and economic lithiations of functionalized arenes and heteroarenes using Cy₂NLi in the presence of Mg, Zn or La halides in a continuous flow

Matthias R. Becker,^a   Maximilian A. Ganiek^a and   Paul Knochel*^a  

*

Corresponding authors

^a

Ludwig-Maximilians-Universität München, Department Chemie, Butenandtstrasse 5-13 (Haus F), 81377 München, Germany
E-mail: paul.knochel@cup.uni-muenchen.de

Chem. Sci., 2015,6, 6649-6653

DOI: 10.1039/C5SC02558C
 http://pubs.rsc.org/en/content/articlelanding/2015/sc/c5sc02558c#!divAbstract


 The economic amide base lithium dicyclohexylamide (Cy₂NLi) allows fast and convenient (40 s, 0 °C) in situ trapping flow metalations of a broad range of functionalized arenes, heteroarenes and acrylate derivatives in the presence of various metal salts (ZnCl₂·2LiCl, MgCl₂, LaCl₃·2LiCl). The resulting Zn-, Mg- or La-organometallic intermediates are trapped with various electrophiles in high yields. These flow metalations are easily scaled-up without further optimization.


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Asymmetric phase transfer catalysis has been recognized as an approach that is greener and more sustainable than synthetic alternatives and has evolved into one of the most practical methods in challenging enantioselective synthesis. An overview of the current status of asymmetric phase transfer catalysis in industry is presented by summarizing research progress from both journal publications and patent applications.

 

Contemporary Asymmetric Phase Transfer Catalysis: Large-Scale Industrial Applications

Jiajing Tan^* and Nobuyoshi Yasuda

Department of Process Chemistry, Merck and Co., Inc., P.O. Box 2000, Rahway, New Jersey 07065, United States

Org. Process Res. Dev., Article ASAP

DOI: 10.1021/acs.oprd.5b00304

Publication Date (Web): September 29, 2015

Copyright © 2015 American Chemical Society

*E-mail: jiajing.tan@merck.com.

 http://pubs.acs.org/doi/abs/10.1021/acs.oprd.5b00304

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A manganese catalyst for highly reactive yet chemoselective intramolecular C( sp 3 ) – Hamination

.

A manganese catalyst for highly reactive yet chemoselective intramolecular C(sp3)–H amination

 http://urlaa.com/Manganese-Catalyst-CH-activation.pdf

http://bit.ly/1LuzWSU 

A 10 million times more abundant metal than rhodium, Manganese within a complex showed high reactivity and in the same time high selectivity to make precious molecules that can speed up Drug development. #manganesecomplex #catalyst #drugdiscovery #drugdevelopment

An odorless, one-pot synthesis of nitroaryl thioethers via SNAr reactions through the in situ generation of S-alkylisothiouronium salts

A newly developed C–S bond formation nucleophilic aromatic substitution (S_NAr) reaction in aqueous Triton X-100 (TX100) micelles has been disclosed. This chemistry, in which odorless, cheap and stable thiourea in place of thiols is used as the sulfur reagent, provides an efficient approach for the generation of nitroaryl thioethers, which are useful structural units of many bioactive molecules, rendering this methodology attractive to both synthetic and medicinal chemistry.

An odorless, one-pot synthesis of nitroaryl thioethers via S_NAr reactions through the in situ generation of S-alkylisothiouronium salts

Guo-ping Lu*^a and   Chun Cai^a  

*Corresponding authors

^aChemical Engineering College, Nanjing University of Science & Technology, Nanjing, P. R. China
E-mail: glu@njust.edu.cn

RSC Adv., 2014,4, 59990-59996

DOI: 10.1039/C4RA11490F

http://pubs.rsc.org/en/content/articlelanding/2014/ra/c4ra11490f#!divAbstract
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Fatty acid sugar esters are non-toxic, odorless, non-irritanting surfactants. They can be synthesized by renewable resources and are completely biodegradable in aerobic and anaerobic conditions. Their application has been expanded in innumerous areas including pharmaceuticals, cosmetics, detergents and food industry. Lipase-catalyzed esterification have been investigated as a potential substitute to the traditional chemical, demanding milder reaction conditions, allowing better reaction control and providing higher-quality products. So, the lipase catalyzed sugar ester synthesis becomes an interesting strategy for producing biodegradable, non- ionic surfactants. The main disadvantage of this protocol is the poor solubility of substrates and long reaction time required for performed the esterification reaction with moderated to good yields.

Synthesis of 2,3:4,5-O-diisopropylidene-D-frutopyranose (FK) (2)

In a 2000 mL reactor was added 30 g (44.8 mmol) of sucrose and 400 mL of acetone being vigorously mechanically stirred at 5°C for 15 min. Then, 16 mL of concentrate sulfuric acid (H₂SO₄) was slowly added to the reaction mixture. The solution was kept under stirring for 150 min. Subsequently, the reaction mixture was cooled (0–10°C) in ice bath and neutralized with 50% NaOH (w/v). The pH was adjusted with saturated sodium carbonate. The final mixture was filtered to remove the solids and subsequently, the solvent was evaporated under reduced pressure. The solid crude ketal was diluted with 400 mL of dichloromethane. A 0.5 M H₂SO₄ solution was added and stirred vigorously for 120 min. The organic phase was separated and washed consecutively with sodium bicarbonate (NaHCO₃) and water and dried with anhydrous sodium sulfate (Na₂SO₄). The solvent was evaporated under reduced pressure until obtaining a white solid, which was crystallized in hexane with 30% final yield after filtration through activated charcoal [19].

Continuous flow reaction procedure

An equimolar stock solution (tert-butylmethyl ether (MTBE), toluene or p-cymene) of 2,3:4,5-O-D-diisopropylidene frutopyranose (FK) and the RePO was prepared (the molarity of the residue was expressed in palmitic acid). The starting mixture was stirred for 5 min while the instrument Asia Flow Reactor was equipped with Omnifit column (2.4 mL) containing the immobilized lipase from R. miehei(600 mg). The reaction parameters were selected on the flow reactor, and processing was started, whereby only pure solvent was pumped through the system until the instrument had achieved the desired reaction parameters and stable processing was assured. At this point, the inlet pipe of the flask was switched to HPLC bottle containing the prepared reaction mixture. After processing through the flow reactor, the inlet tube was dipped back into the flask containing respective pure solvent and processed in order to wash the system of any remaining reactant.

Enhanced production of fructose ester by biocatalyzed continuous flow process

Felipe K Sutili¹, Halliny S Ruela¹, Daniel De O Nogueira¹², Ivana CR Leal², Leandro SM Miranda¹ and Rodrigo OMA De Souza^1*

• *Corresponding author: Rodrigo OMA De Souza rodrigosouza@iq.ufrj.br

¹Biocatalysis and Organic Synthesis Group, Chemistry Institute, Federal University of Rio de Janeiro, Rio de Janeiro CEP 22941 909, Brazil
²Faculdade de Farmácia, Federal University of Rio de Janeiro, Rio de Janeiro CEP22941909, Brazil
http://www.sustainablechemicalprocesses.com/content/3/1/6

Sustainable Chemical Processes 2015, 3:6  doi:10.1186/s40508-015-0031-8
The electronic version of this article is the complete one and can be found online at:http://www.sustainablechemicalprocesses.com/content/3/1/6

Rodrigo O. M. A. de Souza

PhD Organic Chemistry

Professor Adjunto III

Federal University of Rio de J..., Rio de Janeiro

• 
  Federal University of Rio de Janeiro

  Departamento de Química Orgânica

  Rio de Janeiro, RJ, Brazil

https://www.researchgate.net/profile/Rodrigo_De_Souza4
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Firming COFs up takes Michael reaction catalysis forward

Jiang's team took this covalent organic framework and modified it to make it more stable © NPG Firming COFs up takes Michael reaction catalysis forward
	Chemists stabilise hexagonal layers that form nanochannels, which help speed up conversions

see

http://www.rsc.org/chemistryworld/2015/09/firming-cofs-takes-michael-reaction-catalysis-forward

By making formerly fragile covalent organic frameworks (COFs) resistant to harsh conditions, researchers in Japan have created what they think could be a powerful new catalyst concept. Donglin Jiang’s team at the National Institutes of Natural Sciences in Okazaki have already used their chiral COFs to enable selective and high-yielding Michael reactions with low-reactivity ketones. They believe theirs is the first example of a heterogeneous catalyst based on a crystalline porous material used in this reaction.

Dongling
 jiang
Tel: +81-564-59-5520

Fax: +81-564-59-5520

jiang@ims.ac.jp

Institute for Molecular Science, National Institutes of Natural Science

Sokendai (Graduate University for Advanced Studies)

5-1 Higashiyama, Myodaiji, Okazaki 444-8787, Japan

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Recent Developments in Chemistry of Phthalazines

From hydrazine and hydrazine derivatives

Hydrazine and hydrazine derivatives are the most common reagents used for the synthesis of phthalazinone derivatives via their reactions with phthalic anhydride, phthalides, phthalimides etc.

Hydrazines with anhydrides: Several methods were reported for the preparation of phthalazinones derivatives. These methods mainly involve the reaction of phthalic anhydrides with hydrazine hydrate in the presence of acetic acid [42-44].

Phthalazinones 5,7-9 were synthesized from commercially available phthalic anhydride in 2-3 steps as depicted in (Scheme 1 and 2) [45-51].

Additionally, reaction of phthalic anhydride and aromatic hydrocarbons in the presence of anhydrous aluminum chloride under Friedel-Craft’s conditions afforded 2-aroylbenzoic acids 10 which treated with hydrazine hydrate and hydrazine derivatives to give the phthalazine (2H)-1-one 11,12 [52-57] (Scheme 3).

Recent Developments in Chemistry of Phthalazines
Fatma SM Abu El-Azm*, Mahmoud R Mahmoud, and Mohamed H Hekal
Chemistry Department, Faculty of Science, Ain Shams University, Abbassia, Cairo, Egypt
Corresponding Author :	Fatma SM Abu El-Azm Chemistry Department Faculty of Science Ain Shams University, Abbassia Cairo, Egypt, Post code 11566 Tel: 0201220383276 E-mail: ftmsaber@yahoo.com
http://www.omicsonline.org/open-access/recent-developments-in-chemistry-of-phthalazines-2161-0401.1000132.php?aid=40611
Citation: El-Azm FSMA, Mahmoud MR, Hekal MH (2015) Recent Developments in Chemistry of Phthalazines. Organic Chem Curr Res 4:132. doi: 10.4172/2161-0401.1000132

Chemistry Department
Faculty of Science
Ain Shams University, Abbassia
Cairo, Egypt








/////Phthalazine derivatives,  Pyrazolophthalazines,  Indazolophthalazines,  [1,2,4] Triazolophthalazines, Fatma SM Abu El-Azm