Limits...
Strategic Application of Residence-Time Control in Continuous-Flow Reactors.

Mándity IM, Ötvös SB, Fülöp F - ChemistryOpen (2015)

Bottom Line: As a sustainable alternative for conventional batch-based synthetic techniques, the concept of continuous-flow processing has emerged in the synthesis of fine chemicals.Systematic tuning of the residence time, a key parameter of continuous-reaction technology, can govern the outcome of a chemical reaction by determining the reaction rate and the conversion and by influencing the product selectivity.Such a fine reaction control cannot be performed in conventional batch reaction set-ups.

View Article: PubMed Central - PubMed

Affiliation: Institute of Pharmaceutical Chemistry, University of Szeged Eötvös u. 6, H-6720, Szeged, Hungary.

ABSTRACT
As a sustainable alternative for conventional batch-based synthetic techniques, the concept of continuous-flow processing has emerged in the synthesis of fine chemicals. Systematic tuning of the residence time, a key parameter of continuous-reaction technology, can govern the outcome of a chemical reaction by determining the reaction rate and the conversion and by influencing the product selectivity. This review furnishes a brief insight into flow reactions in which high chemo- and/or stereoselectivity can be attained by strategic residence-time control and illustrates the importance of the residence time as a crucial parameter in sustainable method development. Such a fine reaction control cannot be performed in conventional batch reaction set-ups.

No MeSH data available.


CF thermolysis of 5-benzoyl Meldrums acid leading to different products, depending on the residence time.12
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4522171&req=5

sch03: CF thermolysis of 5-benzoyl Meldrums acid leading to different products, depending on the residence time.12

Mentions: Kappe and co-workers recently reported the highly controlled thermolysis of various substrates in a high-pressure/high-temperature microreactor environment, employing near- or supercritical fluids as reaction media.12 The method relies on exact control of the temperature and the flow rate, and hence, the residence time for the fine-tuning of the chemoselectivity. In the case of 5-benzoyl Meldrums acid, for example, differential scanning calorimetry studies revealed that the thermolysis largely depends on the reaction conditions. At ∼150 °C, a 1,3-dioxin-4-one intermediate is formed, which decomposes to an α-oxoketene dimer at higher temperatures (Scheme 3).


Strategic Application of Residence-Time Control in Continuous-Flow Reactors.

Mándity IM, Ötvös SB, Fülöp F - ChemistryOpen (2015)

CF thermolysis of 5-benzoyl Meldrums acid leading to different products, depending on the residence time.12
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4522171&req=5

sch03: CF thermolysis of 5-benzoyl Meldrums acid leading to different products, depending on the residence time.12
Mentions: Kappe and co-workers recently reported the highly controlled thermolysis of various substrates in a high-pressure/high-temperature microreactor environment, employing near- or supercritical fluids as reaction media.12 The method relies on exact control of the temperature and the flow rate, and hence, the residence time for the fine-tuning of the chemoselectivity. In the case of 5-benzoyl Meldrums acid, for example, differential scanning calorimetry studies revealed that the thermolysis largely depends on the reaction conditions. At ∼150 °C, a 1,3-dioxin-4-one intermediate is formed, which decomposes to an α-oxoketene dimer at higher temperatures (Scheme 3).

Bottom Line: As a sustainable alternative for conventional batch-based synthetic techniques, the concept of continuous-flow processing has emerged in the synthesis of fine chemicals.Systematic tuning of the residence time, a key parameter of continuous-reaction technology, can govern the outcome of a chemical reaction by determining the reaction rate and the conversion and by influencing the product selectivity.Such a fine reaction control cannot be performed in conventional batch reaction set-ups.

View Article: PubMed Central - PubMed

Affiliation: Institute of Pharmaceutical Chemistry, University of Szeged Eötvös u. 6, H-6720, Szeged, Hungary.

ABSTRACT
As a sustainable alternative for conventional batch-based synthetic techniques, the concept of continuous-flow processing has emerged in the synthesis of fine chemicals. Systematic tuning of the residence time, a key parameter of continuous-reaction technology, can govern the outcome of a chemical reaction by determining the reaction rate and the conversion and by influencing the product selectivity. This review furnishes a brief insight into flow reactions in which high chemo- and/or stereoselectivity can be attained by strategic residence-time control and illustrates the importance of the residence time as a crucial parameter in sustainable method development. Such a fine reaction control cannot be performed in conventional batch reaction set-ups.

No MeSH data available.