The Odd Oxygen

There is a weird smattering of organic oxides whose molecules contain a foreign oxygen latched on to an otherwise familiar framework. I’ve written about DMSO before, which is essentially dimethyl sulfide with an extra oxygen atom along for the ride. N-Oxides fit into this group of compounds as well.

The structure of nitrous oxide, also known as laughing gas.

Nitrous oxide (also known as laughing gas).

Perhaps no molecule better typifies the class than nitrous oxide, N2O. Even the molecular formula sets off neural fireworks: that can’t be right. A central nitrogen flanked by N and O? Something’s wrong here. The central nitrogen seems overworked, while the oxygen seems to be missing a bond. Despite its bizarre structure, nitrous is surprisingly unreactive—I learned this recently while helping out a teacher friend with one of his students’ science fair projects. Thanks to its lack of reactivity at sane temperatures, detecting N2O is a pain.

Synthesizing nitrous, on the other hand, is quite easy. Upon heating, ammonium nitrate breaks down into N2O and two water molecules. The melting point of NH4NO3 is downright eye popping for an ionic compound: 170 ºC. Some rather unsafe methods actually produce nitrous from molten ammonium nitrate at high temperatures.

NH4NO3(l) → N2O(g) + 2 H2O(g)

One must be careful as the dissociation of ammonium nitrate into gaseous nitric acid and ammonia competes with N2O formation (“decomposition”).

NH4NO3(l) → HNO3(g) + NH3(g)

Dissociation is endothermic and decomposition exothermic, so heating can set up an interesting situation where the dissociation reaction can “quench” the heat released by decomposition. When dissociation is suppressed, the decomposition reaction can become a runaway exotherm. Although this document on the safe production of nitrous oxide from ammonium nitrate is written for chemical engineers—they even go to the trouble of writing out “gram-mole”!—it’s an illuminating read with some additional information about the synthesis of nitrous oxide. Continue reading →

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BRSM Blog Party: Good Luck in the States!

Blog parties: what a phenomenal idea. This is my contribution to the #BRSMBlogParty for the purveyor of the famous BRSM blog, who’s heading toward the west side of the pond soon.

What’s your message for BRSM?

Good luck, have fun, and be nice to the graduate students!

Any post-doc survival tips?

Not being a post-doc myself, I can’t speak from direct experience, but the best post-docs I have known have maintained their cool in the face of a lot of pressures. Graduate students (and others) will look up to you, but don’t let that pressure get to you—be yourself. Don’t be afraid to challenge your advisor. Get out, explore wherever you’ll be, get into a hobby that allows you to meet people and do good work (for me, it was community theater).

Do you have a fun story to share from your experience in US chemistry academia?

As I mentioned before, be nice to the graduate students. A few years back, a very tall and very strong post-doc came through the lab. His first day, he walked up to me and asked where to find one of the other graduate students…I made the mistake of asking if he was an undergraduate. Talk about not starting things off on the right foot!

Any survival tips for living in the US?

Looking for an adjective? “Awesome” is the American’s go-to.

What would you like to see on BRSM blog in the future?

Whatever you want to write about! Just keep on truckin’.

DMS-Woah?!: From Oxidant to Analgesic?

Edit: Props to Pat Knerr for forwarding along the SI article.

Every chemistry teacher has moments when students ask…odd questions. I had one such moment last week, when a student hung around after class to ask me what I knew about DMSO (yes organickers, that DMSO). A friend had advised the student to use DMSO on a running-related injury. Organic chemists know DMSO as the world’s most annoying NMR solvent and an oxidant…was there any truth to these claims of pain relief? After lowering the figurative raised eyebrow, I decided to investigate.

A Lewis structure of dimethyl sulfoxide

A Lewis structure of dimethyl sulfoxide.

DMSO is perhaps the world’s most famous sulfoxide, and it sits on the oxidation ladder between the abhorrent dimethyl sulfide (Me2S) and dimethyl sulfone (Me2SO2). The latter has an interesting medical history of its own, as we’ll see shortly. DMSO may be used as a polar solvent in organic reactions, but it also finds application in the Swern oxidation and other alkoxysulfonium-based oxidations—organickers, check out the Pfitzner-Moffatt oxidation too. All those applications, of course, have nothing to do with the medicinal effects of DMSO. Could a choice reagent for oxidations also have anti-inflammatory and analgesic effects? Continue reading →

Temporary Break – Back in a Jiffy

My prelim exam is coming up in October, so I’ll probably be out of commission until then. But, the latest issue of J. Chem. Educ. and its ASAPs are actually quite good, so take a look if you’re interested in what’s abuzz in the chemical education world. Thirty-second lit review coming soon…

I don’t exactly know what the typical submit-to-publish time is for research science publishing, but consider the fact that this article on editing Wikipedia just came out on ASAPs, and the last edit to the article’s featured page (by the authors’ class) was made in the summer of 2009. Come on JCE!

New Name, Same URL

Excimer‘s marvelous talk at ACS has inspired me to take up blogging again. However, as my interests have changed substantially since I started MGW back in 2007, I’ve decided to re-cast MGW as “Cheersical Education,” so named for “Cheers, Mike,” my signature e-mail signoff. Here I’ll post about developments in chemical education, literature reviews, life in the lab (watching it from my office across the hall) and other random junk like that. I’ll leave you with this:

Blog: Short for weblog. A meandering, blatantly uninteresting online diary that gives the author the illusion that people are interested in their stupid, pathetic life. Consists of such riveting entries as “homework sucks” and “I slept until noon today.” v. intr. The act of posting to a weblog. (Source)

MGW 2.0 – Now with Blogtastic Blogablogs!

I figure it’s about time for a triumphant return. With Kentucky in reasonably clear site of an NCAA title, my spirits are invigorated and I’m ready to take on the slings and arrows of the blogosphere. I’ll be posting here about organic chemistry, life, women, whatever. And yes (in case you were wondering…), Wednesday Night Problems will be making a comeback in the near future.

So what’s the deal with ACS Mobile?! It’s an app that allows you to read papers from ACS Pubs on the go. Cool—for a guy who spends essentially zero time at work reading non-essential papers, it’s nice to have that option, I thought. Gee whiz, I thought, maybe they’ve built a whole new mobile publication interface. That’d be—what the deuce?!?! $2.99 at the App Store?! That’s right ladies and gents, ACS Mobile is going to cost you three times as Running Log, infinity times as much as Facebook and Pandora combined, and three times as much as renting Cube from That’s Rentertainment. Screw it; I’d rather watch a dude get chopped in half three times—paying for it each time—than pay three bucks to read journal articles on my iPod Touch. Sorry ACS.

…at least, that was my reaction two days ago. Slowly, over the past couple of days, guilt has been eating away at me. The ACS always has a way of pulling me back. Kind of like hipster chicks—it’s just so hard to let them go. They’re just…so damn cool. Finally, in a moment of weakness, I caved and bought the app today. I’ll try to keep the remainder of this review, in contrast to the first half of it, at least marginally more objective.

Positives: The interface is really nice. It’s not exactly new, but it’s nice. You won’t find yourself zooming with frustration on abstracts very often (full text is a different story). The text is HUGE, and resolution on the figures is superb. You can select what journal ASAPs you want to see, and filter content to look only at results from a specific journal. You can also save articles, because “JESUS CHRIST WHAT WOULD I DO IF I LOST THAT PAPER ON YET ANOTHER ENANTIOSELECTIVE DIELS-ALDER REACTION?!” Abstracts load quickly, but I found navigating the articles (which appear in PDF form) to be a little laggy. Great for blazing through abstacts, though. Landscape mode is a nice touch.

Negatives: Price is going to be your biggest minus with this thing. The verdict’s still out for me in terms of paying for itself in usefulness. You also can’t set time limits on what it displays, as far as I can tell. I realize $2.99 isn’t exactly filet mignon, but for what you get, it’s almost easier—almost—to just use ACS Pubs’s website. The full-text interface needs to improve, but this isn’t all ACS’s fault—navigating PDFs has never been fun on the iPhone.

Overall: If you’re a grad student who feels like you need to read more papers but you don’t have time, spring for it. If you already feel inundated with literature during the bulk of your work day (I feel like this might be a common sentiment among readers…comment and let me know?), then skip it.

On Break

As I’m sure regular visitors have noticed, things haven’t been too exciting around here for a while. In lieu of boring you with all the gory details, I’ll just say that MGW is going on a little “break” for the time being. Regular posting should resume sometime in the summer. Until then, enjoy this. LSD optional.