Friday, April 17, 2009

awww ... that's so cute

The dreamy P. S. Baran just published yet another JACS paper!

One of the things that I find amusing about this particular publication is that they very proudly proclaim "Gram-Scale, Enantiospecific Total Syntheses of Kapakahines B (1) and F (2)", and the whole scheme represents six steps. They even re-comment [gram-scale] under four of the six steps so you can be sure as to which are done on this huge, huge scale.


The other wonderus addition in this landmark effort is his new custom arrows! Those plain old arrows for schemes in ChemDraw must not have been up to his standards. I bet in the coming months those of you in academia will be deluged by student presentations using these jewels, and other similar knock offs. Another wonderful fluff addition (like the utterly useless chemoselective) courtesy of TSRI.

Well I'm off to work up my reaction. I had took 86 g of impure material laying around from prior runs of step 2. I figured I'd push it through in hopes of having > 1 g at step 7.

7 comments:

Jim said...

But he's so dreamy. . .

Mike said...

When? Like 10 years ago?

j said...

didn't we just have some discussion about inventing some kind of "synthesis design" arrows? Along the lines of we modeled this target from this known molecule.

Brandon said...

This thing just drips fuckin' class. Gettattaheeeeeeeere!
How did this get through peer review? Tim?

Dr. Miller said...

I have often thought about the "scalability" issue. Aside from concentration gradients and temperature gradients, what makes reactions not work on "gram scale"? It seems like pressure and temp issues could be easily addressed by being careful, slow addition, etc. Why don't we just assume a rxn is scalable unless you tell us otherwise.

scientist 1 said...

In theory that's true, but there are always things that go unnoticed. Not to mention there's scaling up, and then there's really scaling up. My boss likes to use a specific example of a reaction that went to a pilot plant; there was a small exotherm that no one noticed at gram scale, that caused it to run away and basically blow up on multi kilo scale.

Interestingly I run into a reaction once every six months or year that seems to be hurt if it is run too slowly. Of course I like to run additions and temperature increases more slowly as I scale up, to avoid problem like the exotherm, and get bitten in the ass.

I suppose the point is, everything is scalable, but the effort to scale up can be as great as the original optimization.

Tim said...

I'm guessing Bob didn't have the balls to pass along my suggestion to change the title to "Diastereoselective Synthesis..."