As Chemistry.SE has grown, we have created many tags to help classify questions. I have been responsible for some of them, and I am also very glad to see others chip in with their expertise in proposing tags, applying them to questions, and doing up tag wikis. So I would like to begin with a sincere thank you to those who have put in hard work into these.
However, as the number of tags grows, we also need to be careful about the tags we create. Tags should generally be specific and help to identify areas or subdisciplines of chemistry that are of interest to people. At the end of the day, the primary use of tags is for users to easily search for or highlight questions which they are interested in.
I am beginning to have some concerns about our tags, especially those pertaining to organic chemistry, which tends to get a lot more exposure on our site. Ultimately, the problem is that we can only place five tags on a question – this is a system-imposed restriction. If we continue to add and apply new tags, we will run into a problem where more than five tags are potentially applicable. In fact, we have arguably already ran into this problem.
Here are some perfectly reasonable questions, and potentially applicable tags, which illustrate the point.
I read about an asymmetric Strecker synthesis of amino acids, catalysed by thiourea (Jacobsen, Nature 2009, 461, 968–970). Why does the reaction select for this particular enantiomer?
- organic-chemistry; carbonyl-compounds; amino-acids; stereochemistry; selectivity; catalysis; organosulfur-compounds; reaction-mechanism
Why does the C-4 chlorine in 2,4-dichloropyrimidine undergo Suzuki coupling preferentially? see: Selectivity in Suzuki coupling of 2,4-dichloropyrimidine
- organic-chemistry; heterocyclic-compounds; selectivity; transition-metal; catalysis; halides; organoboron-compounds
Is there a name for the synthesis of an indole from 2-nitrotoluene and diethyl oxalate, followed by the addition of zinc dust? (There is: Reissert synthesis)
- organic-chemistry; carbonyl-compounds; esters; nitro-compounds; heterocyclic-compounds; aromatic-compounds; terminology; redox
Hopefully you can see where I am coming from. I do not think the way forward is entirely clear, and I do not think that one single meta post will be able to solve all the problems. I think there are some particular tags that we need to look at carefully to evaluate whether they are actually useful, and in the coming days/weeks we will hopefully see more concrete and specific proposals on meta. For now, though, I just want to bring this issue to your attention, and provide some context for the discussion that will ensue.
If you have any thoughts on the matter – maybe you have an idea of a tag which should be reworked, or maybe you disagree with me that it is a problem(!) – please let us know in the answer box.