Archive for the ‘chemistry’ Category

August 13, 2007

August 13, 2007

The summer will be winding down soon and I am hoping to get back on track with posting.

There is an interesting paper from David Milstein (Weizmann Institute of Science) in the August 10th issue of Science describing the synthesis of amides from alcohols and amines. The method employs a special Ruthenium catalyst that effects the removal of two equivalents of H2, as shown below, in order to form the amide group. What makes this method attractive is that it requires only a small amount of catalyst, 0.1 mol%, and is stoichiometric for both the alcohol and amine starting materials. Nonetheless, it might be hampered by the fact that the catalyst must be handled under strictly controlled Argon-atmosperic conditions (Glove box) and so far has only been demonstrated on millimolar scale reactions.

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Intermolecular ene reaction

March 29, 2007

This a little overdue…Some interesting chemistry reported in Journal of the American Chemical Society….Interesting not for the products that it produces but for the proposed mechanism, an intermolecular ene-reaction. From a retrosynthetic point of view one can imagine that the product of thisreaction could also be formed just as easily from the corresponding aldehyde via and Aldol reaction instead. However, the authors provide evidence to show that the reactants, as their enols, go through an ene-type process.

Given that this reaction occurs at room temperature simply by mixing the two substrates together is also noteworthy and makes me wonder why nobody had reported this before.

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