Week 7 - Admin begins...

Everything has arrived!  Pretty much at least.  I’ve finally been able to set up my vacuum line and get the Schlenks in the oven, so chemistry will begin in earnest next week.  It’s taken quite a while to get set up but speaking to some people a little bit more senior they seem pretty impressed it didn’t take longer.  Slight issues with the glovebox may cause problems in time but for now we should be able to begin!

The admin has also begun, with the undergraduate curriculum review going on this week.  It was a brutal 3-hour long meeting and was a bit of an eye-opener as to how universities actually work. The department’s priority is clearly (and rightly) undergraduate teaching but I suspect the people involved at this are somewhat blinkered and not considering other ‘customers’, academics need time for postgraduate and other work!  But it is exciting.

Continued being able to read papers…

5)      Structurally controlled mechanochemistry under hydrostatic pressure, Melosh and co-workers, Nature, 2018, 554, 505-510
Really interesting conceptually piece where it is shown that pressure on a solid can have molecular chemical effects.  The species (Carb-M-S; Carb = carborane) has a mechanosensitizer (the carbornane – the anvil!), whereas the M-S core can be seen as compressible.  Chemically when compressed the Cu(I) goes to Cu(0)!

6)      Thermal, catalytic conversion of alkanes to linear aldehydes and linear amines, Huang et al., JACS, 2018, 140, 4157
A two-phase catalytic process, first step is Goldman’s catalyst to dehydrogenate the alkane and then a Rh catalyst to convert it to aldehydes, amines and silanes.  Pretty neat stuff, but only done on C5 and higher – I wonder if they could do it on gaseous alkanes…

7)      Anthracene as a launchpad for a phosphinidene sulphide and for generation of a phosphorous sulfur material having the composition P2S, a vulcanized red phosphorus that is yellow, Cummins et al., JACS, DOI: 10.1021/jacs.8b10775
Cummins has previously used anthracene as a diazomethane transfer agent, here he uses it for tBuPS transfer.  Which is nice enough (they show its reaction with low valent platinum, and butadiene.  They try to get HPS as the transfer agent, but it doesn’t really work, they get an intractable solid which they submit to a barrage of techniques, but (in my opinion) it isn’t definitely shown to be P2S.

8)      Intrinsic reactivity of diatomic 3d transition-metal carbides in the thermal activation of methane: Striking electronic structure effects , Schwarz et al., JACS, DOI: 10.1021/jacs.8b11739
A mostly computational (with some experiment) paper about the activation of CH4 with [MC]+. Shows that primarily three papers are at work, ‘proton coupled electron transfer’, ‘hydrogen atom transfer’ and ‘hydride transfer’.  Summary is that early transition metals have the biggest thermodynamic driving force but it is pretty complex…

9)      Pi-bond character in metal-alkyl compounds for C-H activation: How, When and Why? Coperet et al., JACS, DOI: 10.1021/jacs.8b11951
Another brutal NMR paper, where they investigate the individual tensors to get the orbital make up of Cp*2M-CH3.  It is a HUGE amount of NMR, and is pretty complex, but has a really important conclusion: sigma-bond metathesis, olefin insertion and olefin metathesis are actually isolobal despite sigma bond metathesis appearing to not involve pi orbitals!  Definitely worth a read! Also the paper has a conclusion and an epilogue…

Mark Chadwick