Farewell Dan!

Here's to Dan, who left Aus today as he got a job back in Denmark.

Dan has been one of the people responsible for bringing me up into the harsh world of chemistry, and he was a great mentor. I owe a lot to him as he was one of the two people in my life who really motivated me to study and do chemistry. I would've never gone this far without his hekp. Nevertheless, his valuable insight during discussions and group meetings will be greatly missed!

All the best to you Dan! Hope to see you in the future! Thanks so much once again for all the inspiration and help over the past year (and your 2nd year chem lectures!).

Towards a greater understanding...

Here a great article about why chemist and biologist do not very often see eye to eye, taken from the RSC website.

http://www.rsc.org/chemistryworld/Issues/2008/June/ColumnInpipeline.asp

Yes, lets hope that this communication gap will slowly decrease over the next few decades....

KK

How May passed by....

Hi everyone.... Here's a breakdown of what happened in May 2008:

09/05/2008 - Honours thesis due

22/05/2008 - Honours presentation (~ 25mins including questions)

28/05/2008 - Oral examination (1 hour)

30/05/2008 - Results (There was only the 2 of us, so results were released pretty quick)

So much for May.... Anyways, now that we are free (kinda), we will try to blog again... no more MIA sessions.

Cheers!

KK

Thesis Writing

My apologies to the readers (if any) out there. Both the bloggers are currently engaging their Honours thesis. Rest assured, posting will resume after the 9th of May.

Cheers,

KK

Northern Lights

Here's some pictures taken a while a go. Lights were projected on the buildings along NT in Adelaide. We just happened to be there when we finish work, so we decided to look around.

Bonython Hall in all its gothic medieval glory... its hard to look at that place and think too much about it, since its used for graduation ceremonies as well as supplementary exams. Here's a mid-day comparison.

Still freaky huh?


This one here is the Elder Hall...very flowery and pinkish... The next one up is the Mithell building... with a more funky bright green and yellow comnbinations...


Spiderman did the next one to us....notice the cool ghostly images of other people in the background?


The winner of the most floral design for the night goes to.....The library of SA! The Institute that is...


In my opinion, the best display for the night was the SA museum, although some might disagree. The archeological design was really impressive, and it was well in agreement with the museum theme... This is very subjective however, and those wishing for funky colours & contemporary art would be disappointed.

In fact, I liked it so much that I even put up 2 pictures for it!


The 'real' state library though..... whilst still magnificently bright at night, I think its a waste of electricity...


Another nice one...


Some funky disco mood for the younger generation.... just bare with me... it will be over soon...


And the grand finale.... that's all for now folks, gotta head up to cook dinner for the big boss!



KK.

The Claisen Rearrangement & the oil bath...

Hi all,

Once again, I'm finally back into the blogging mood. I know its a little late, but let me just say, HAPPY 2008! All the stress, coursework, labwork & family issues have taken its toll on me, not to mention the time needed for me to recuperate from these event. Well, all I can say is that I'm finally back & I will try to be as productive as possible.

A while ago, when I started my Honours labwork around the Sept-Oct period, I had to do a Claisen rearrangement. For those of you that do not know what this is, the Claisen rearrangement is a [3,3]-sigmatropic rearrangement of an allyl vinyl ether bond, accompanied by the rearomatisation of the ring to form an allyl phenol under THERMAL conditions. Why did I emphasise thermal conditions? Well, sigmatropic rearrangment occurs under 2 distinctly different conditions; thermal and photochemical.

In the example below, 2-allylphenol is formed via an aromatic claisen rearrangement. Let me say that whilst the "normal" Claisen rearrangement had been repeated in literature countless of times, aromatic Claisen rearrangements were hard to find in literature. Many failed attempts have been reported on aromatic Claisen rearrangements.


As I was saying, very early on in my Honours degree, I was trying to get the reaction to work. Well, we did lean about it in undergrad and the reaction seemed fairly simple; heat the compound up neat at 300 degrees C for 2 hours. What could go wrong?

Well, first off, your compound turns black. Secondly, it becomes all viscous and isomers would form if your molecule has other substituents in it. In my case, I had 2 Cl substituents meta and para to the phenol group. Okay, I had a crappy reference (it was from a patent, the only one i could find on the formation of 2-allyl-3,4-dichlorophenol).

Further investigation prompt the use of an organic solvent, in this case, N,N-diethylaniline. After refluxing for about 5 days at 300 degrees C, some of the SM actually turned to the TM, with a 5:3 ratio of the TM to the unwanted isomer. Still, that wasn't good enough as I had only done the reaction on a very small scale (bout 100 mg). Purification would be a pain in the buttocks.

I then looked up some articles and found another interesting solvent used for the Claisen rearrangement carried out in the microwave, m-xylene. This however, favours the formation of the unwanted isomer, so this was scrapped.

We then had a microwave demonstration (not the household version, you can't make instant noodles in this one because its too small) & I decided to carry it out again under different conditions; 600W at 250degrees C for 15 mins. The nice yellow fluid turned black (as expected) when it was done. The NMR also suggested that the majority of the compound was the unwanted isomer.

Due to all the frustration, we decided to abandon this & try a different analogue. Of course, there are tons of ways to attach an alkyl group next to the phenol group. Then, sometime early February this year, I found an interesting article regarding the aromatic Claisen rearrangement with the use of 1,2-dichlorobenzene. I thought I would give it a go since there was nothing to lose form it & viola, I've got 2-allyl-3,4-dichlorophenol! The reflux took 3 days at 200 degrees C. The isomer was present in a 2:1 ratio [TM:isomer] but this time it was easier to purify.

I went on to make more since it was just a trial. So this time I had about 1.00 g of my compound in the solvent. Guess what happened after 3 days?

Here's Markus, one of the postdocs in my lab holding up my oil bath.... Yes, very high and continuous heat had caused the silicon oil to polymerise into a blob of slime. Hilarious if you ask me, since when I first saw it, I tought there was something wrong with my reaction. The temperature of the oil bath was at room temp, & the RBF looked as if it was sitting on top of a jelly. Still, the oil bath did retain its oiliness. I'm also supprised that the oil did not turn brown (or black in some case) even after going through such vigorous heat. I've heard from some of my postdocs that the oil they had used in the past were all brown and oily, so I guess I'm really lucky to have good quality oil for my oil baths (unlike those they use in the undergrad labs, which were either brown or black).

Thats the end of my funny post for now.

KevK

My 1st light scattering

Do anyone know what is this?? This is my poor attempt to find out is there any micelles in a pH 13 solution using light scattering. Well, the reason that I said it's poor because I can hardly see the scattering.

Well, this picture is much better as you may see the fade red laser beam going through the solution and that is due to the micelle in the solution scatter the light. I know it's not obvious but literature suggests that there are micelles. So I think the hypothesis still holds and the paper will soon be done.

And now I just need to concentrate on the coursework and think about what I can do afterwards.

Long time no post~

Yes, this blog is boring. It's because lack of post.

Yes, there is no post. It's because I am very busy (and lazy as well......).

And yes, luckily you are reading a post from a very busy chemist wanna be.

And NO, I think I better stop here and get back to wrok!