Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

All that Glitters is Gold

07.01.2011
Gold Cyclization Reaction Provides Important Building Blocks for Pharmaceuticals

In many significant natural products, furans are a key motif. These oxygen-containing five-membered heterocycles are also versatile building blocks in the construction of highly complex target structures. As such, they are important scaffolds in organic and pharmaceutical chemistry.

As reported in the European Journal of Organic Chemistry, A. Stephen K. Hashmi and a team at Universität Heidelberg (Germany) have now introduced a general protocol for the preparation of highly substituted furans through a gold-catalyzed cyclization reaction.

The efficiency of reactions is often thought of in terms of atom economy, and the search for more efficient alternatives to classical chemical reactions is now an area of intense research. In this context, transition-metal catalysts are becoming a popular choice amongst chemists, because they are often used in only very small amounts, which conforms to the atom-economy rule and minimizes waste. Notably, in contrast to the often harsh conditions required to perform classical chemical transformations, most transition-metal catalyzed reactions can be performed under mild reaction conditions and within a short timeframe.

Because gold catalysts are robust, their popularity has increased significantly in the last few years. Gold catalysts can easily be handled in air, and they are also tolerant to water. Moreover, gold catalysts often show higher activity and higher selectivity than their more popular palladium counterparts. Gold is particularly well suited for substrates that bear a triple carbon–carbon bond (i.e., an alkyne), as it coordinates preferentially to this bond, resulting in a highly reactive complex that is prone to attack. As such, the gold-catalyzed cyclization of an alkyne tethered to an alcohol can provide easy access to highly substituted furans.

The German research team found that the gold(I)-catalyzed cyclization of various 2-alkynylallyl alcohols proceeded well and afforded the desired furan products with the use of low catalyst loadings under very mild reaction conditions. Importantly, both di- and trisubstituted furans could be obtained, which allows structural variety in the building blocks. Bifunctional substrates could also be cyclized to provide chemically interesting bisfurans. This synthetically simple route provides quick and easy access to highly substituted furan building blocks, which may help to facilitate the study of this important class of compounds.

Author: A. Stephen K. Hashmi, Universität Heidelberg (Germany),

Title: Cyclization of 2-Alkynylallyl Alcohols to Highly Substituted Furans by Gold(I)–Carbene Complexes

European Journal of Organic Chemistry, Permalink to the article: http://dx.doi.org/10.1002/ejoc.201001479

A. Stephen K. Hashmi | Wiley-VCH
Further information:
http://www.wiley-vch.de

Further reports about: Cyclization Glitters building block chemical reaction

More articles from Life Sciences:

nachricht Antimicrobial substances identified in Komodo dragon blood
23.02.2017 | American Chemical Society

nachricht New Mechanisms of Gene Inactivation may prevent Aging and Cancer
23.02.2017 | Leibniz-Institut für Alternsforschung - Fritz-Lipmann-Institut e.V. (FLI)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

From rocks in Colorado, evidence of a 'chaotic solar system'

23.02.2017 | Physics and Astronomy

'Quartz' crystals at the Earth's core power its magnetic field

23.02.2017 | Earth Sciences

Antimicrobial substances identified in Komodo dragon blood

23.02.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>