Wednesday, April 17, 2013

Precious Serendipity

Serendipity often drives scientific inquiry.

Ask a famous scientist - Feynman, Archimedes, Fleming, to name a few beneficiaries - they'd tell you it's better to be lucky than good. But Pasteur's paraphrased "Fortune favors the prepared mind" spells things out more clearly; diving into the nitty-gritty of chemical transformations often brings up a chance pearl of wisdom.

Such is the case for a recent JACS ASAP, out of the Wang group at Xiamen University in China. Let's set the stage: the scientists attempt to create a stabilized bimetallic cluster compound from gold, silver, and hemilabile P-N ligands. When the starting Ag-Au complex meets acetonitrile and methanol, something interesting occurs: a dimeric crystalline compound forms, bridged by two fully deprotonated acetonitriles!
Those golden pyramids are pretty schnazzy.
Source: JACS | Wang group
So, why am I so excited?

1. That's a CCN (3-) anion stuck in there! What if you could, say, build a tetra-substituted carbon center just by adding electrophiles in sequence?

2. C-H activation of sp3 bonds = hard. Especially at room temp.
Well, there's (technically) 6 sp3 C-H bonds missing in that complex!

3. The authors note that water forms as the reaction progresses. Most nitriles, in the presence of Au/Ag catalysts and water, will hydrate to form amides. Not so here.

4. The authors point out that a gold oxo intermediate must be present for the cluster to form. They also point out that similar gold oxo catalysts (and silver oxide bases) pop up in the literature. Perhaps crazy intermediates like this commonly arise in gold-catalyzed reactions?

The best part? Studies like this always leave you with more questions than answers.
Perfect fodder for future projects.

1 comment:

  1. Yeah, that bridging deprotonated MeCN is pretty darn cool. Definitely curious to hear more about this system.