Some commenters in a previous thread took umbrage at the fact that I admit to judging people by their grammar. Well, I do, and I’m not going to change anytime soon. I’ll put poor grammar on par with poor hygiene, dressing like a slob, and bad table manners—while they don’t automatically invalidate a person’s ideas, they will cause me to treat anything the person says with more skepticism than usual. With respect to the four errors I found in the first paragraph of this recent paper from Org. Lett., the misplaced apostrophe in “Evan’s” was the most aggravating. While the chemistry in the paper was good, as The Chem Blog has noted, the authors’ lack of attention to detail was borderline disrespectful. I expected more from one of the most storied labs in synthetic organic chemistry.
A lot of people will complain, “So what if I make a few mistakes? Why don’t you focus on the ideas?” That’s the thing: I want to focus on your ideas, so why don’t you stop whining and learn to write properly? The rules of grammar are not up for discussion—just follow them out of courtesy to your readers. Grammatical errors are distracting and will cause them to lose sight of what you’re writing. If you are someone who has no trouble reading documents riddled with mistakes, that’s great, but when you are writing, you aren’t writing for yourself.
While grammar shouldn’t be the sole criterion for evaluating intelligence, I will admit to judging some things by a relatively obscure set of criteria. For instance, I have a list of favorite subjects for judging textbooks and course packets. One of the first things I do to determine the quality of a sophomore organic textbook is to look in the index for phenol. As you all know, phenol is more acidic than “standard” aliphatic alcohols. If you took a survey, most people would ascribe this fact to a resonance effect by drawing the following structures:
There are a number of variations on this theme, including drawing out all of the unhybridized p orbitals and showing that an orbital on oxygen containing a lone pair can overlap with the pi system, thereby allowing for increased delocalization of the extra negative charge density.
It turns out that an inductive effect—not a resonance effect—is the predominant reason for the increased acidity of phenol relative to aliphatic alcohols. Whereas aliphatic alcohols have a C(sp3)—O bond, the carbon to which the hydroxyl group is bonded in phenol is sp2 hybridized. The increased s-character of the carbon orbital used to form the C—O bond makes it more electron withdrawing, which leads to greater stabilization of the conjugate base of the alcohol. For the purpose of comparison, look at the pKa of phenol compared to that of enol tautomer of acetone:
Even though you can only draw two resonance forms showing delocalization of the extra negative charge in the conjugate base of the enol (vs. four for phenol), the acidities of the two protons differ by less than an order of magnitude. For those interested, these data come from Evans’ Chem 206 lecture notes (
Lecture 20, restricted access), where the point is hammered home in glorious detail. Professor Evans’ PowerPoint slides should be framed and displayed in the Smithsonian.
While we’re discussing phenol and errors, let me also use this example to illustrate one of the main problems with Wikipedia. Wikipedia is great, but it is home to a number of edit-happy users who think they know more than they actually do. If you look at the discussion page for phenol, someone actually addressed the resonance vs. inductive effect argument, but was unceremoniously (mis)corrected by another user, who references an incorrect explanation on the Internet. Thus, the main article (as of today) gives the incorrect (resonance > inductive) explanation:
Phenol has a limited solubility in water (8.3 g/100 ml). It is slightly acidic: the phenol molecule has weak tendencies to lose the H+ ion from the hydroxyl group, resulting in the highly water-soluble phenoxide anion C6H5O−. Compared to aliphatic alcohols, phenol shows much higher acidity; it even reacts with NaOH to lose H+ whereas aliphatic alcohols do not. This is due to orbital overlap between the oxygen’s lone pairs and the aromatic system, which delocalizes the negative charge throughout the ring and stabilizes the anion. This effect is attenuated, however, due to oxygen’s relatively high electronegativity. [1]
God knows that we in the chemical blogosphere love the Wikipedia, but read it with skepticism.
This concludes today’s lesson. Your homework for the weekend is to find all of the grammatical errors in this post. For extra credit, find an error in a chemistry article on Wikipedia, fix it, and brag about having done so in the comments. Class dismissed.
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