07Feb 2013 by Vincent Summers No Comments

Decarboxylation of Carboxylic Acids Useful in Synthesis

Chemistry
For one reason or another, it may be desirable to remove a carboxylic acid group (–COOH) from a molecule. This process is called, logically, decarboxylation. It may be the carboxylic group was previously introduced to guide some of steps in a synthesis. What? A Simple Example Consider the simple hexagonal ring, aromatic compound benzene, C6H6. From the top and clockwise, let's number the carbon atoms, one through six. If we wish to attach a group synthetically to the ring, how do we determine the ring carbon to which it will attach? It's simple. They're all identical. Whichever carbon atom it does attach to becomes the number one carbon atom! But say we want to attach another group to the No. 2 carbon atom. Well, in this situation, the carbon atoms…
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04Feb 2013 by Vincent Summers 2 Comments

Epoxide Ring Preparation by Oxidation of Alkenes

Chemistry
How many have purchased a 2-tube pack of epoxy at their local hardware or grocery store? It’s a routine item we use to repair a variety of objects. But what is it that makes epoxy glue so strong? Its name gives it away. Epoxy glues use epoxy compounds. Epoxides. What is an epoxide? It’s Simple? Yes An epoxide is a molecule with a tiny 3-member ring in its structure. One atom is oxygen. Two are carbon. The epoxy link is illustrated in Figure 1. R₁, R₂, R₃, and R₄ are pendant groups. How is such a 3-member ring created? Often by the oxidation of an alkene. The reader may appreciate an example.1 Propene Let's try the oxidation of propene, CH3CH=CH2.2 What would be a suitable oxidizing agent for the reaction?…
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21Jan 2013 by Vincent Summers No Comments

Vorticella – a Living Spring

Biology
Among microscopic aquatic creatures, it is the most bizarre. Vorticella looks like an upside down bell attached to a pull rope. That pull rope is actually a fibril or stalk called a myoneme,1 which has, running down its middle, an internal organelle. This spasmoneme contracts into a spring or corkscrew shape, as seen in the video below. Why is Vorticella of Interest Scientists are not ashamed to learn from the lowly creature. The contraction and elongation of its stalk appears to depend on the binding and re-release of calcium ions by the protein spasmin. What makes this of special interest is no ATP (adenosine triphosphate) is necessary to achieve the task, though ordinarily, it plays a vital role in muscle function. High Tech Plumbing? Curiously, it has been suggested this…
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