Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation

Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...

Regioselective Formation of Enolates

Regioselective Formation of Enolates

As depicted in the figure below, the unsymmetrical ketones can form two possible enolates: less substituted or more substituted enolates. Usually, the thermodynamic enolates are formed from the more substituted α-carbon atom, while the kinetic enolates are formed faster by deprotonation from the less substituted position. The thermodynamic enolates have lower energy, so they are more stable. But the energy required to form kinetic enolates is less.

Regioselectivity of Electrophilic Additions to Alkenes: Markovnikov's Rule

Regioselectivity of Electrophilic Additions to Alkenes: Markovnikov's Rule

If a set of reactants can yield multiple constitutional isomers, but one of the isomers is obtained as the major product, the reaction is said to be regioselective. In such reactions, bond formation or breaking is favored at one reaction site over others.
The hydrohalogenation of an unsymmetrical alkene can yield two haloalkane products, depending on which vinylic carbon takes up the halogen. However, one product usually predominates, where hydrogen adds to the vinylic carbon bearing the...

Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration

Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration

The rate of acid-catalyzed hydration of alkenes depends on the alkene's structure, as the presence of alkyl substituents at the double bond can significantly influence the rate.

Thermal Electrocyclic Reactions: Stereochemistry

Thermal Electrocyclic Reactions: Stereochemistry

The stereochemistry of electrocyclic reactions is strongly influenced by the orbital symmetry of the polyene HOMO. Under thermal conditions, the reaction proceeds via the ground-state HOMO.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.

Stereochemical Effects of Enolization

Stereochemical Effects of Enolization

The chiral α-carbon of the carbonyl compound is the stereocenter of the molecule. As shown in the figure below, when such a carbonyl compound undergoes racemization under an acidic or basic condition, an achiral enol is formed.

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Spiropyran-based glutamate nanovalve for neuronal stimulation.

Materials horizons·2025

Same author

[Self-harming behavior of patients on a closed psychiatric ward].

Tijdschrift voor psychiatrie·2023

Same author

Clinically explainable machine learning models for early identification of patients at risk of hospital-acquired urinary tract infection.

The Journal of hospital infection·2023

Same author

High-retention membrane bioreactors for sugarcane vinasse treatment: Opportunities for environmental impact reduction and wastewater valorization.

Journal of environmental management·2022

Same author

Localizing the human brain response to olfactory stimulation: A meta-analytic approach.

Neuroscience and biobehavioral reviews·2021

Same author

Filtered Diffusion-Weighted MRI of the Human Cervical Spinal Cord: Feasibility and Application to Traumatic Spinal Cord Injury.

AJNR. American journal of neuroradiology·2021

Search research articles

Related Experiment Video

Updated: Jul 11, 2026

Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks (MOFs)

Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks (MOFs)

Published on: January 17, 2020

Enzymatic enantioselective C-C-bond formation in microreactors.

K Koch¹, R J F van den Berg, P J Nieuwland

¹Radboud University Nijmegen, Institute for Molecules and Materials, Toernooiveld 1, NL-6525 ED Nijmegen, The Netherlands.

Biotechnology and Bioengineering

|September 20, 2007

Summary

Crude enzyme lysates in microreactors enable efficient enantioselective synthesis of cyanohydrins. This microreactor method allows rapid screening of reaction parameters with minimal reagent use.

More Related Videos

Utilization of Stop-flow Micro-tubing Reactors for the Development of Organic Transformations

Utilization of Stop-flow Micro-tubing Reactors for the Development of Organic Transformations

Published on: January 4, 2018

Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy

Versatile CO₂ Transformations into Complex Products: A One-pot Two-step Strategy

Published on: November 9, 2019

Related Experiment Videos

Last Updated: Jul 11, 2026

Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks (MOFs)

Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks (MOFs)

Published on: January 17, 2020

Utilization of Stop-flow Micro-tubing Reactors for the Development of Organic Transformations

Utilization of Stop-flow Micro-tubing Reactors for the Development of Organic Transformations

Published on: January 4, 2018

Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy

Versatile CO₂ Transformations into Complex Products: A One-pot Two-step Strategy

Published on: November 9, 2019

Area of Science:

Biocatalysis
Organic Synthesis
Chemical Engineering

Background:

Enzyme catalysis offers a green route for synthesizing valuable chemical compounds.
Hydroxynitrile lyases (HNLs) are key enzymes for cyanohydrin production.
Microreactor technology provides enhanced control and efficiency in chemical synthesis.

Purpose of the Study:

To investigate the use of crude enzyme lysates containing hydroxynitrile lyase (HNL) in microchannels for enantioselective cyanohydrin synthesis.
To demonstrate the efficiency of microreactor systems for screening reaction parameters.
To compare microreactor results with traditional batch processes.

Main Methods:

Utilizing microreactor setups for continuous flow synthesis.
Employing crude enzyme lysates with hydroxynitrile lyase activity.
Screening key reaction parameters within the microreactor system.
Comparing continuous flow results with batchwise synthesis.

Main Results:

Successful enantioselective synthesis of cyanohydrins from aldehydes was achieved using HNL-containing enzyme lysates in microchannels.
Microreactor experiments allowed for efficient screening of two critical parameters with minimal reagent consumption.
Continuous flow reaction outcomes were consistent with those from larger-scale batch processes, even in the presence of stable emulsions.

Conclusions:

Crude enzyme lysates are effective biocatalysts for enantioselective cyanohydrin synthesis in microreactors.
Microreactor technology offers a scalable and efficient platform for enzyme-catalyzed reactions and parameter optimization.
The findings support the viability of continuous flow biocatalysis for industrial applications.