Posts Tagged ‘Bob Hanson’

Test of JSmol in WordPress: the background story.

Sunday, June 8th, 2014

A word of explanation about this test page for experimenting with JSmol. Many moons ago I posted about how to include a generated 3D molecular model in a blog post, and have used that method on many posts here ever since. It relied on Java as the underlying software (first introduced in 1996), or almost 20 years ago. Like most software technologies, much has changed, and Java itself (as a compiled language) has had to move to improve its underlying security. In the last year, the Java code itself (in this case Jmol) has needed to be digitally signed in a standard manner, and this meant that many an old site that used unsigned older versions has started to throw up increasingly alarming messages.

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Non covalent interactions in the Sharpless transition state for asymmetric epoxidation.

Wednesday, December 19th, 2012

The Sharpless epoxidation of an allylic alcohol had a big impact on synthetic chemistry when it was introduced in the 1980s, and led the way for the discovery (design?) of many new asymmetric catalytic systems. Each achieves its chiral magic by control of the geometry at the transition state for the reaction, and the stabilizations (or destabilizations) that occur at that geometry. These in turn can originate from factors such as stereoelectronic control or simply by the overall sum of many small attractions and repulsions we call dispersion interactions. Here I take an initial look at these for the binuclear transition state shown schematically below.

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“Text” Books in a (higher) education environment.

Friday, May 18th, 2012

Text books (is this a misnomer, much like “papers” are in journals?) in a higher-educational chemistry environment, I feel, are at a cross-roads. What happens next?

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