Saturday, July 08, 2006

Highs and Lows

Hello all,

ell, another weekend is here and I can believe it. This week has flown by faster than any since I got here. Right now I am on the train to Kyushu, still trying to figure out if it was such a good idea to bring the computer. Man, it makes my backpack so heavy, but I don’t think I could have made it so long without it(my memory card will be filled after the first day). Anyway, this week has flown by, but we have done much during the week, some good, and some…well…not so great.


The biggest chemistry new was an iodohydrine reaction that we did in the middle of the week. The iodohydrine is a main component every single one of the target molecules that we are trying to make. Because of this fact, we need a lot of it, and it is much easier to make it here because we do not have to make one of the main reagents. Luckily, Dr. Yamamoto bought it so that we wouldn’t have to go through all the hassles that we had in Alabama (I think we finally got everything worked out, but it is nice to skip that step). The only reason that we didn’t do this in Alabama is because the epoxide is very expensive (about $300 for 25 g.). We did a small scale reaction with a couple of grams of epoxide and everything worked fine so we did a larger scale reaction with 25g, and thing worked fine again(our yield was about 18 g. (less than 50%), but still not that bad). We knew that we would need a lot of it, so we decided to do a very large scale reaction with 50 g. of the epoxide. I figured we would get somewhere around 40 g. of the iodohydrine, and you can’t imagine the feeling I had when we finished the workup and only had 15g. I don’t even have words to describe the feeling. This was about a 20% yield, which meant we had lost about $480 worth of starting material somewhere between the beginning and the end of the reaction. Besides the monetary cost, it was more than half of the epoxide we had ordered, and it took over a month for it to get to Japan, so we can’t even get more before I leave. We have managed to recover a bit more but we are still only have about 25g. and have little hope of getting much more from the reaction. We have enough Iodohydrine for the chemistry here, and I guess we are just going to have to figure out the rest when Gabi, Yamamichi, and I are back in Tuscaloosa.


That was not the only thing that happened this week. I started the recrystallization of another new imidazole before I left last weekend, and when I got back, I was amazed to see some huge crystals. They are probably the largest ones that have ever come out of one of my recrystallizations. I was very excited (this was before the iodohydrine incident), and I couldn’t wait to take pictures and post them. I then talked to Dr. Arduengo and learned large crystals usually still have to many impurities still. Smaller, whiter crystals were better, and I would have to break up my pretty crystals and do another recrystallization. I was going to do that till I had all the trouble with the iodohydrine.

I finally got to the recrystallization Friday morning, and to my surprise and almost disappointment the new crystals were as big, if not bigger than the first ones. We had to start a reaction with it so we didn’t have any other choice but to use them. I just took some of the large crystals out and to use, and we will see next week whether nor not the crystals were good. I was in the lab till after 12 trying to get the reaction started, but now that it is going, I am getting out of here. As I have mentioned before, there is a chemistry conference that is only in Japanese, so I am going on a little trip. This time, I have decided to go to Kyushu, the large island below the main island. There is a typhoon somewhere, but the forecasters can’t figure out exactly where it is going to go. First, they said it was going to hit the east part of Kyushu. Then it was the west part of the island. Now, it looks like it will be Korea or China. I am just going to take my chances and see what happens.


Till next time,


Josh

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