A couple of weeks ago, Roy Periana (Scripps Florida) published this paper in Science detailing his latest work on C-H activation of alkanes. Honestly, I don’t understand why this was published in Science; the biggest issue is that this reaction uses stoichiometric amounts of thallium or lead! If you read the paper, Periana cleverly skirts around that rather glaring issue…kudos to him for his clever rhetoric. The other issue is that doing electrophilic reactions/C-H activation with late transition or d10 metals is not that difficult; Periana’s initial successes were with catalytic mercury in sulfuric acid, and later with Au in selenic acid. Since Tl(III) and Pb(IV) are isoelectronic with Hg(II), I’m not surprised by this latest report.
C&EN’s hype of this paper, though, just made me facepalm. These two sentences are almost comedy gold:
“[…] a research team including Brian G. Hashiguchi and Roy A. Periana of Scripps Research Institute Florida and Daniel H. Ess of Brigham Young University has discovered that inexpensive main-group thallium and lead complexes work well at converting the typically unreactive alkanes in natural gas into alcohol esters […]”
Uh, but Tl(TFA)3 is $336/25g (Strem), and this is only for technical grade product! I can’t find pricing information for Pb(TFA)4, since it is not commercially available. Reading the SI for this paper reveals that the authors synthesized the Tl and Pb complexes! C&EN needs to get their facts straight before making claims that these are “inexpensive”.
“Periana says the team is in discussions with several companies and entrepreneurs and would ideally like to jointly develop the technology with a petrochemical company or spin off a start-up company. […]”
Who, I ask WHO is going to start a company based on a process that uses stoichiometric amounts of thallium or lead? Thallium, like arsenic, is incredibly toxic, and there is absolutely no way the EPA would greenlight it. Governments worldwide have gone to a lot of effort to remove lead from gasoline since it is known to be a neurotoxin; starting a company like this, based on a process that would potentially use tons of those metals, would be counterproductive.
I hope the chemistry community collectively facepalmed like I did upon reading this tripe by C&EN; if not, well, then here is one reason why people these days don’t really respect chemists anymore…