New developments in 'ene'-reductase catalysed biological hydrogenations.
Helen S Toogood1, Nigel S Scrutton1
1Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, UK.
Current Opinion in Chemical Biology
|March 11, 2014
Summary
Asymmetric biocatalytic hydrogenations, primarily using Old Yellow Enzymes, create valuable chiral molecules. Recent advances focus on new enzymes, cascading reactions, and cost-effective technologies for industrial applications.
Area of Science:
- Biocatalysis and Organic Chemistry
Background:
- Asymmetric biocatalytic hydrogenations are key for synthesizing chiral molecules.
- The Old Yellow Enzyme family is a primary catalyst for these reactions.
- These reactions generate up to two stereogenic centers, crucial for synthons.
Purpose of the Study:
- To review recent progress in asymmetric hydrogenation biocatalysis.
- To highlight new enzyme classes and multienzyme cascading reactions.
- To focus on industrially relevant advancements and technologies.
Main Methods:
- Literature review of research from the last two years.
- Analysis of enzyme classes beyond the Old Yellow Enzyme family.
- Examination of novel biotransformation technologies.
Main Results:
- Identification of additional enzyme classes for asymmetric hydrogenation.
- Examples of successful multienzyme cascading reactions presented.
- Discussion of technologies improving commercial viability, including coenzyme-independent reactions.
Conclusions:
- Significant progress has been made in asymmetric hydrogenation biocatalysis.
- New enzymes and cascade reactions offer expanded synthetic potential.
- Technological innovations are enhancing the industrial applicability of these biotransformations.
![Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F55858.jpg&w=3840&q=50)
Related Concept Videos
02:17Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
2.6K
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...
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...
2.6K
02:13Reduction of Alkenes: Catalytic Hydrogenation
12.4K
Alkenes undergo reduction by the addition of molecular hydrogen to give alkanes. Because the process generally occurs in the presence of a transition-metal catalyst, the reaction is called catalytic hydrogenation.
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
12.4K
02:24Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
6.9K
Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
6.9K
01:28Reduction of Benzene to Cyclohexane: Catalytic Hydrogenation
5.6K
Unlike the easy catalytic hydrogenation of an alkene double bond, hydrogenation of a benzene double bond under similar reaction conditions does not take place easily. For example, in the reduction of stilbene, the benzene ring remains unaffected while the alkene bond gets reduced. Hydrogenation of an alkene double bond is exothermic and a favorable process. In contrast, to hydrogenate the first unsaturated bond of benzene, an energy input is needed; that is, the process is endothermic. This is...
5.6K
01:18Reactivity of Enols
3.4K
Enols are a class of compounds where a hydroxyl group is attached to a carbon–carbon double bond, which implies that it is a vinyl alcohol. A carbonyl compound with an α hydrogen undergoes keto–enol tautomerism and remains in equilibrium with its tautomer, the enol form. Usually, the keto tautomer is present in a higher concentration than the enol tautomer due to the higher bond energy of C=O compared to C=C. Moreover, the direction of the keto–enol equilibrium is...
3.4K
01:33Regioselective Formation of Enolates
2.6K
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.
2.6K