This is a follow-up to the post on exploring the directing influence of (electron donating) substituents on benzene[cite]10.1021/acs.jchemed.5b00346[/cite] with the focus on heteroaromatic rings such indoles, pyrroles and group 16 analogues (furans, thiophenes etc). The search query is shown above (and is available here[cite]10.14469/hpc/665[/cite]). As before, the distance is compared from an electrophile, modelled as

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.