Selective reduction of ketones using water as a hydrogen source under high hydrostatic pressure.
Summary of "Selective reduction of ketones using water as a hydrogen source under high hydrostatic pressure."
A selective reduction of a broad variety of ketones is described. The method is based on the combination of a Ni-Al alloy and high hydrostatic pressure (HHP, 2.8 kbar) in an aqueous medium. The reaction of the Ni-Al alloy with water provides in situ hydrogen generation and the high pressure ensures that the H(2) formed remains in the solution, thus the C[double bond, length as m-dash]O reduction readily occurs. The application of the HHP resulted in selective formation of the desired products and the common problem of non-selective overhydrogenation could be avoided. In most cases the reductions resulted in high yields and excellent selectivities without the use of any base.
Affiliation
University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA, USA. bela.torok@umb.edu.
Journal Details
This article was published in the following journal.
Name: Organic & biomolecular chemistry
ISSN: 1477-0539
Pages:
Links
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/22868406
- DOI: http://dx.doi.org/10.1039/c2ob25941a
Medical and Biotech [MESH] Definitions
Acids
Chemical compounds which yield hydrogen ions or protons when dissolved in water, whose hydrogen can be replaced by metals or basic radicals, or which react with bases to form salts and water (neutralization). An extension of the term includes substances dissolved in media other than water. (Grant & Hackh's Chemical Dictionary, 5th ed)
Mixed Function Oxygenases
Widely distributed enzymes that carry out oxidation-reduction reactions in which one atom of the oxygen molecule is incorporated into the organic substrate; the other oxygen atom is reduced and combined with hydrogen ions to form water. They are also known as monooxygenases or hydroxylases. These reactions require two substrates as reductants for each of the two oxygen atoms. There are different classes of monooxygenases depending on the type of hydrogen-providing cosubstrate (COENZYMES) required in the mixed-function oxidation.
Hydrogen Bonding
A low-energy attractive force between hydrogen and another element. It plays a major role in determining the properties of water, proteins, and other compounds.
Water Supply
Source, means, or process of supplying water (as for a community) usually including reservoirs, tunnels, and pipelines and often the watershed from which the water is ultimately drawn. (Webster, 3d ed)
Thioredoxins
Hydrogen-donating proteins that participates in a variety of biochemical reactions including ribonucleotide reduction and reduction of PEROXIREDOXINS. Thioredoxin is oxidized from a dithiol to a disulfide when acting as a reducing cofactor. The disulfide form is then reduced by NADPH in a reaction catalyzed by THIOREDOXIN REDUCTASE.
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