Nitrile Oxide 1,3-Dipolar Cycloaddition by Dehydration of Nitromethane Derivatives Under Continuous Flow Conditions

2011 ◽  
Vol 64 (10) ◽  
pp. 1397 ◽  
Author(s):  
Malte Brasholz ◽  
Simon Saubern ◽  
G. Paul Savage
Keyword(s):  
Continuous Flow ◽  
Reaction Times ◽  
Nitro Compounds ◽  
Dipolar Cycloaddition ◽  
Flow Conditions ◽  
Nitrile Oxides ◽  
Aliphatic Nitrile ◽  
By Products ◽  
Flow Techniques

Aliphatic nitrile oxides were generated in situ, by dehydration of terminal nitro compounds, and reacted with dipolarophiles using continuous flow techniques to afford substituted isoxazolines. The yields of cycloadducts were comparable with traditional flask-based reactions but reaction times were much shorter. In-line scavenger cartridges conveniently removed by-products and unreacted reagents to give almost pure crude products. The process was demonstrated up to gram scale.

scholarly journals Continuous-flow synthesis of primary amines: Metal-free reduction of aliphatic and aromatic nitro derivatives with trichlorosilane

2016 ◽  
Vol 12 ◽  
pp. 2614-2619 ◽  
Author(s):  
Riccardo Porta ◽  
Alessandra Puglisi ◽  
Giacomo Colombo ◽  
Sergio Rossi ◽  
Maurizio Benaglia
Keyword(s):  
Continuous Flow ◽  
Reaction Times ◽  
Nitro Compounds ◽  
Primary Amines ◽  
Flow Conditions ◽  
Metal Free ◽  
Nitro Derivatives ◽  
Aromatic Nitro ◽  
High Yields ◽  
First Time

The metal-free reduction of nitro compounds to amines mediated by trichlorosilane was successfully performed for the first time under continuous-flow conditions. Aromatic as well as aliphatic nitro derivatives were converted to the corresponding primary amines in high yields and very short reaction times with no need for purification. The methodology was also extended to the synthesis of two synthetically relevant intermediates (precursors of baclofen and boscalid).

scholarly journals The Eschenmoser coupling reaction under continuous-flow conditions

2011 ◽  
Vol 7 ◽  
pp. 1164-1172 ◽  
Author(s):  
Sukhdeep Singh ◽  
J Michael Köhler ◽  
Andreas Schober ◽  
G Alexander Groß
Keyword(s):  
Continuous Flow ◽  
Elevated Temperatures ◽  
Reaction Times ◽  
Coupling Reaction ◽  
Flow Chemistry ◽  
Flow Conditions ◽  
Reaction Conditions ◽  
Bond Forming ◽  
Carbon Carbon Bond ◽  
Reaction Proceeds

The Eschenmoser coupling is a useful carbon–carbon bond forming reaction which has been used in various different synthesis strategies. The reaction proceeds smoothly if S-alkylated ternary thioamides or thiolactames are used. In the case of S-alkylated secondary thioamides or thiolactames, the Eschenmoser coupling needs prolonged reaction times and elevated temperatures to deliver valuable yields. We have used a flow chemistry system to promote the Eschenmoser coupling under enhanced reaction conditions in order to convert the demanding precursors such as S-alkylated secondary thioamides and thiolactames in an efficient way. Under pressurized reaction conditions at about 220 °C, the desired Eschenmoser coupling products were obtained within 70 s residence time. The reaction kinetics was investigated and 15 examples of different building block combinations are given.

Asymmetric 1,3-Dipolar Cycloaddition of Nitrile Oxides Generated in situ by Direct Oxidation of Aldoximes

2002 ◽  
Vol 31 (11) ◽  
pp. 1112-1113 ◽  
Author(s):  
Masamichi Tsuji ◽  
Yutaka Ukaji ◽  
Katsuhiko Inomata
Keyword(s):  
Dipolar Cycloaddition ◽  
Direct Oxidation ◽  
Nitrile Oxides

An efficient entry to 1,2-benzisoxazoles via 1,3-dipolar cycloaddition of in situ generated nitrile oxides and benzyne

2010 ◽  
Vol 8 (11) ◽  
pp. 2537 ◽  
Author(s):  
Christian Spiteri ◽  
Christopher Mason ◽  
Fengzhi Zhang ◽  
Dougal J. Ritson ◽  
Pallavi Sharma ◽  
...  
Keyword(s):  
Dipolar Cycloaddition ◽  
Nitrile Oxides

scholarly journals Dimeric cyclobutane formation under continuous flow conditions using organophotoredox catalysed [2+2]-cycloaddition

2021 ◽  
Author(s):  
Helena Grantham ◽  
Marc Kimber
Keyword(s):  
Natural Products ◽  
Continuous Flow ◽  
Reaction Times ◽  
Functional Materials ◽  
Synthetic Route ◽  
Flow Conditions ◽  
Reaction Conditions ◽  
New Class ◽  
Cyclobutane Dimers ◽  
Flow Study

Radical cation-initiated dimerization of electron rich alkenes is an expedient method for the synthesis of cyclobutanes. By merging organophotoredox catalysis and continuous flow technology a batch versus continuous flow study has been performed providing a convenient synthetic route to an important carbazole cyclobutane material dimer t-DCzCB using less only 0.1 mol% of an organophotoredox catalyst. The scope of this methodology was explored giving a new class of functional materials, as well as an improved synthetic route to styrene based lignan dimeric natural products. The cyclobutane dimers could be isolated in higher chemical yields under continuous flow conditions and reaction times were reduced significantly compared to traditional batch reaction conditions.

scholarly journals Biofilm dynamics: linking in situ biofilm biomass and metabolic activity measurements in real-time under continuous flow conditions

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Kyle B. Klopper ◽  
Riaan N. de Witt ◽  
Elanna Bester ◽  
Leon M. T. Dicks ◽  
Gideon M. Wolfaardt
Keyword(s):  
Real Time ◽  
Metabolic Activity ◽  
Continuous Flow ◽  
Control Strategies ◽  
Mass Function ◽  
Flow Conditions ◽  
Carbon Dioxide Evolution ◽  
Activity Measurements ◽  
The Internet Of Things

Abstract The tools used to study biofilms generally involve either destructive, end-point analyses or periodic measurements. The advent of the internet of things (IoT) era allows circumvention of these limitations. Here we introduce and detail the development of the BioSpec; a modular, nondestructive, real-time monitoring system, which accurately and reliably track changes in biofilm biomass over time. The performance of the system was validated using a commercial spectrophotometer and produced comparable results for variations in planktonic and sessile biomass. BioSpec was combined with the previously developed carbon dioxide evolution measurement system (CEMS) to allow simultaneous measurement of biofilm biomass and metabolic activity and revealed a differential response of these interrelated parameters to changing environmental conditions. The application of this system can facilitate a greater understanding of biofilm mass–function relationships and aid in the development of biofilm control strategies.

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