Two-headed chemical mayhem!

Saturday, March 10, 2007

Possible answer to Sam's question

One of our loyal blog readers, Sam, wished to know how primary alcohols were iodinated using triphenylphosphine, iodine and imidazole. Here is it, courtesy of petr: In any case have fun in the thursday morning seminars, Samuel! I wish I was there to see a certain first year PhD student write his messy structures (if you can call them that) on the board together with sound effects. Bob Woodward would surely be turning in his grave!


Sunday, February 18, 2007

Interesting chemistry articles

So I thought I might post something chemistry-related - something I haven't done in a while. Below are three papers I have read recently.
After reading almost any of Fujita's papers, I always think to myself "wish I would have published that". His work is simple (in theory), which gives it an intangible elegance. Here (J. Am. Chem. Soc. 2007, 129, 1850) he uses light to labilise his Pt-pyridyl metallocyclic systems to give the thermodynamically more stable (due to hydrophobic effects/pi-pi stacking) catenated dimers. This takes only minutes under UV light, whereas days are required if it's heated instead. Not a new concept, but nice application and mechanistic insight (photochemical mechanism is dissociative, thermal one is associative, which is of course most common for square-planar complexes).
Another cool paper, also in the field of coordination chemistry, is a recent review by Nitschke (Acc. Chem. Res. 2007, 40, 103) highlighting some nice dynamic combinatorial-style work. Most people (myself included) just abhor the prospect of a mixture of products from a reaction - this guy (who, like many top supramolecular chemists, is of the Lehn pedigree) loves them! Anyway, the point of this work is that, unlike Sanders or Fujita (whose work primarily uses labile covalent and coordination bonds, respectively) Nitschke uses a bunch of very labile interactions and can, depending on the product distribution, quantify and rationalise these contributions.
I'll finish with a paper published by none other than F. Albert Cotton, who recently passed away at the age of 76. The guy was a powerhouse of inorganic chemistry and most undergrads would have consulted Advanced Inorganic Chemistry (co-authored by the Nobel Laureate Geoffrey Wilkinson) at least once during their studies. A 2006 Dalton paper from Cottons group (Dalton Trans. 2006, 3900) is a great read and is perhaps the most thorough analysis of a square/triangle equilibrium to date. The crystallisation of the square and triangle components, along with their X-ray and NMR characterisation (they can each be dissolved and an NMR spectrum acquired before substantial interconversion) allowed for the mixture to be analysed quite simply. While many people give a half-arsed argument when considering such equilibria (triangle formation leads to an entropy increase, due to the formation of more particles, but is higher in enthalpy owing to angle/steric strain) Cotton has done all the work and gets all the thermodynamic numbers out. Full marks to him!

Peace out,


Saturday, February 17, 2007

Tasmania =)

After a long hiatus from blogging, Beaker has returned to report on his expedition to Tasmania, the Island state, which would be hosting IC07 (a meeting of inorganic chemists in Australia). Here is a map for ppl not familiar with Australia:Beaker conducted this journey with certain other chemists from the University of Sydney - as if seeing these nerds every week at uni wasn't bad enough, spending every waking hour around them was more than sufficient to drive him nuts. What was cool, however, was walking around in world heritage areas (which, along with reserves and National Parks account for 36% of Tassie) all day. In particular, our day in Cradle Mountain during which the weather was awesomely fine (this apparently only happens once every ten days), was pretty sweet. Apart from being overly sunburnt, Beaker enjoyed it - here are some pics:We would then journey to the west coast of Tassie, namely to a small (~1000ppl) ex-shipping and convict town called Strahan. The easy-going and laconic nature of this place went down as brilliantly as the local beer - we felt the best way to see this place was on a relaxing cruise around the harbour. What was less relaxing was being in a car with a certain Irish postdoc who, despite his strong stance on lab safety, felt no need to drive in anything other than a suicidal manner. Of course, he turned out to be an awesome quadbiker!
Our last port of call would be sunny Hobart, the location of the inorganic chemistry conference. Hobart has many features that distinguish it from more civillised cities. It appears that the local children have not heard of the concept of attending school. Either that, or school there only really takes up a small fraction of their time, the rest of which may be spent playing with their pet tasmanian tigers, frequenting Legs 'n' Breasts (the local chicken shop) or having a few Cascade Lagers. The scarcity of public transport was also disappointing, with no trains and very few buses/taxis. Having said that, we could walk from our motel to the convention centre, pictured below.
While I probably didn't learn as much stuff or meet as many new people as I had at previous conferences, I still enjoyed myself. The talks I attended (which may or may not represent a small fraction of those I should have attended) were pretty good. The plenary lectures given by Schrock and van Koten turned out to be pretty interesting, as I had expected. The former presented work on the catalytic reduction of dinitrogen (most ppl would have read of this, it's been out for a few years: Science 2003, 301, 76) which may see him get a second Nobel prize if a practical version of his Molybdenum-containing system is developed...

...Anyway, so I'm back in Sydney, in my 3rd year of a PhD...
my work certainly won't lead to any Nobel prizes, I really just want to get done and move on. It's that feeling I always get after conferences - possessing new ideas and a renewed urgency to develop them.

Keep it real, be yourself and stay positive :)


Monday, January 15, 2007

The FANTABULOUS lab timer

A most fantastic device has been invented in our lab recently. It is the all purpose chemistry 4 and a half minute glass! Here is how you too can make your very own device. All you need is two bottles of your choice (preferably empty, but whatever floats your boat), some superglue, some sand, and lastly a piercing implement!

Who really needs an hourglass anyway. An hour really isn't a very practical time period. However 4.5 minutes seems to be the ideal amount of time to do many many lab related things! For example, ever come back to your bench to find your t.l.c plate has overrun? Well no more! With the 4.5 minute glass your t.l.c plates will be full of t.l.c goodness when you return to your bench. (Of course, the 4.5 minute glass has been specially designed to account for variables such as solvent system, plate size, wind velocity etc.)

Here are some other lab related activities you can do in 4.5 minutes:

1) Annoy evil lab mates
2) Set up a column
3) Decide to quit your PhD
4) Act like an idiot and get your friend to take a photo (see picture below)

Of course there are many more, but I will leave suggestions up to our valued blog readers.

Tuesday, January 02, 2007

Beaker faces wrath of Dimroth rearrangement

At the end of 2006 I was messing around with some 1-alkyl-2-aminopyrimidinium-based ligands of type 1 in aqueous solution. For some reason, my ligands were giving weird NMR spectra after heating in water. Turns out Beaker the ignoramus was unaware of some old-school chemistry pioneered by Dimroth in the early 1900's, which predicts the formation of rearranged product 2. This has the alkyl group now stuck to the amino nitrogen atom rather than the pyrimidine nitrogen. The simple hydrolysis and condensation mechanism is depicted below.The reaction is very general - it can occur in a heap of nitrogen heterocycles in which an amino group is alpha to an endocyclic nitrogen atom. So yeah, its back to the drawing board for me =(


Monday, January 01, 2007

Happy New Year!

Well, just in case it wasn't already obvious, Sydney is THE New Year's Eve capital of the world. Here is some proof:

I didn't take the last picture, which explains why it's halfway decent. The thing lit up on the harbour bridge is a gold emerald (i dunno why it's not green). Emeralds evoke ideas of the Emerald City from the Wizard of Oz, which, in turn, alludes to Oz = Australia. I'm sure you'll agree that the logic of our totally awesome country is impeccable!

Heaps of chemical mayhem will be in store for 2007 =)


Friday, December 22, 2006

Festive Season Wishes for One and All

Hi Everybody!

Bunsen and myself are very happy that there are actually people other than us two muppet scientists visiting the blog!

2006 has been a very cool year indeed!

Now Beaker has been talking to Santa the past couple of weeks and has come up with a list of the most popular things people have wished for this Christmas. Check it out:

10. David Hasselfhoff - Pip, a young Kiwi lass in our group has been craving Mitch for quite a while now.....apparently, she's not alone.

9. Tickle me Elmo - A regular favourite

8. Beaker - Shocking, I know!
7. Bunsen - Not so surprising

6. Jackson SLS - The ultimate axe....I want one soooooooo badly

5. You want that reaction that you've been working on for ages to actually work for once!
4. Some B19 glassware

3. Toyota Celica - A sweet-as ride...

2. XBOX360

1. Cork Rings!!!!!!

Bunsen and Beaker wish everyone a Merry Christmas and a Happy New year. We hope everyone gets what they wish for and that nobody receives lumps of coal. 2007 will be an awesome year. Bunsen and Beaker will be in their 3rd yr of PhDing, the make or break year. May next year bring awesome results to your experiments and fun times =)