Archive for February, 2019
Monday, February 18th, 2019
Students learning organic chemistry are often asked in examinations and tutorials to devise the mechanisms (as represented by curly arrows) for the core corpus of important reactions, with the purpose of learning skills that allow them to go on to improvise mechanisms for new reactions. A common question asked by students is how should such mechanisms be presented in an exam in order to gain full credit? Alternatively, is there a single correct mechanism for any given reaction? To which the lecturer or tutor will often respond that any reasonable mechanism will receive such credit. The implication is that a mechanism is “reasonable” if it “follows the rules”. The rules are rarely declared fully, but seem to be part of the absorbed but often mysterious skill acquired in learning the subject. These rules also include those governing how the curly arrows should be drawn.† Here I explore this topic using the Graham reaction.[1]‡
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References
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W.H. Graham, "The Halogenation of Amidines. I. Synthesis of 3-Halo- and Other Negatively Substituted Diazirines1", Journal of the American Chemical Society, vol. 87, pp. 4396-4397, 1965. http://dx.doi.org/10.1021/ja00947a040
Tags:/RT, activation energy, activation free energy, animation, arrow pushing, arrow-head, cellular telephone, Chemical kinetics, chemical reaction, Chemistry, computed energy, Ed Smith, energy, energy maximum, energy minima, energy plot, energy profile, energy surface, free energy, Interesting chemistry, lecturer, mechanism, Natural sciences, Organic chemistry, overall reaction energy, Physical sciences, Reaction rate constant, Resonance, Transition state, Transition state theory, tutor, Tutorial
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Saturday, February 16th, 2019
The title of this post comes from the site www.crossref.org/members/prep/ Here you can explore how your favourite publisher of scientific articles exposes metadata for their journal.
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Tags:Aaron Swartz, Academic publishing, API, Business intelligence, CrossRef, data, Data management, Elsevier, favourite publisher, Identifiers, Information, Information science, Interesting chemistry, Knowledge, Knowledge representation, metadata, mining, ORCiD, PDF, Pre-exposure prophylaxis, Publishing, Publishing Requirements for Industry Standard Metadata, Records management, Research Object, Scholarly communication, Scientific literature, search engine, social media, Technical communication, Technology/Internet, text mining, Written communication, XML
Posted in Uncategorised | 1 Comment »