Posts Tagged ‘benzene’

How does an OH or NH group approach an aromatic ring to hydrogen bond with its π-face?

Wednesday, June 22nd, 2016
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I previously used data mining of crystal structures to explore the directing influence of substituents on aromatic and heteroaromatic rings. Here I explore, quite literally, a different angle to the hydrogen bonding interactions between a benzene ring and OH or NH groups.

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Exploring the electrophilic directing influence of heteroaromatic rings using crystal structure data mining.

Tuesday, June 21st, 2016
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This is a follow-up to the post on exploring the directing influence of (electron donating) substituents on benzene[1] with the focus on heteroaromatic rings such indoles, pyrroles and group 16 analogues (furans, thiophenes etc).

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References

  1. H.S. Rzepa, "Discovering More Chemical Concepts from 3D Chemical Information Searches of Crystal Structure Databases", Journal of Chemical Education, vol. 93, pp. 550-554, 2016. http://dx.doi.org/10.1021/acs.jchemed.5b00346

The melting points from benzene to cyclohexane: a prime example of dispersion forces in action?

Thursday, December 30th, 2010
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One of the delights of wandering around an undergraduate chemistry laboratory is discussing the unexpected, if not the outright impossible, with students. The >100% yield in a reaction is an example. This is sometimes encountered (albeit only briefly) when students attempt to recrystallise a product from cyclohexane, and get an abundant crop of crystals when they put their solution into an ice-bath to induce the crystallisation. Of the solvent of course! I should imagine 1000% yields are possible like this.

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