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31 December 2014 - Blogroll sort of

This blog (if you can call it one) conspicuously does not have a blogroll. Practical reason one: the content management system this blog is written on was conceived before blogs became mainstream and the developer is particularly lazy. Practical reason two: a blogroll is one thing but you only want to collect active blogs. So on the last day of 2014: what else is going on in terms of chemistry blogs in 2014 (excluding the corporates).

Find science gift suggestions at In The Pipeline. Enjoy an image of an ambitious pilot reactor at Org Prep Daily or gas cylinders at chembark and find out how LCD's work at Chemistry Blog. Postdoc musings can be found at The Organic Solution and teaching musing at Just Like Cooking and TEACHING Chemistry. Very appropriately for this time of the year find the chemistry of Champagne at CompoundInterest, how to avoid antifreeze-poisoning at The Chemical Blog and a rum review can be found at Chemistry of the Cocktail. And take the quiz at The Chronicle Flask!

A warning on hydrogen sulfide is available at Adrian Dingle's Chemistry Pages and find out how Henry Rzepa risked his life and his family home as a 12 year old. More on astrochemistry in Tree Town Chem, on photocatalysis at B.R.S.M, on supramolecular chemistry in Synthesising Ideas, on reversible covalent kinase inhibitors at The Curious Wavefunction, on NMR at Practical Fragments and on metathesis at All Things Metathesis

Read about the chemistry of alkanes at James Kennedy and be behind the scenes of a cross-coupling (vodka is a solvent?) at Open Flask and be more behind the scenes of a publication at FX's blog. Practical advise on GC-MS sampling on MJLPHD and a totally serious topic on moustached chemists at Key to Chemistry (remember after Movember comes Decembeard!) Total synthesis people can be found at Synthetic Nature and Interesting Organic Chemistry.

And finally a moving piece at Lamentations on Chemistry. If you do not have time to do any reading consider at least this one.

Another asbestos scare

20 December 2014 - Panic starts here

In 2012 authorities in the the Dutch town of Utrecht cordoned off an entire city street on account of asbestos contamination (Link). If you think that was over the top, the city of Roermond (population 57,000 and also in The Netherlands) did one better this week, they closed the entire city centre. For 4 days. This is what happened. On 16 December a fire destroyed a couple of sheds containing yachts. The roof contained asbestos and a large part of the city centre was contaminated (NOS). The authorities then proceeded to close down a large part of the centre, not allowing anyone in, closing all the shops and closing the train station. Cars and bicycles leaving the affected area were hosed down by the fire brigade and guys in white suits and respirators were seen pretending to clean pavements. In 2012 the Utrecht locals were forcibly evacuated, luckily in 2014 the Roermond locals were only ordered to take of their shoes on entering their homes (NRC).

Does this operation make sense? Plenty of rain should ultimately wash away most of the asbestos, collecting in the waterways. The fire department efforts may help. As long the asbestos fibers are in an aquatic environment they are harmless. But what about asbestos collecting in gutters and parks? Cleaning that up classified as chemical waste is going to cost a lot of money, with a questionable impact on health. If a overreaction award exists the Roermond mayor is sure to win.

A giant wheel

02 December 2014 - Organic chemistry

MayGiantWheel2014.PNGMay, Jester and Höger report on a new giant of a molecule IN JACS (DOI). This blog has been taken an interest in chemical giants before. Here are the characteristics: it is a C1878H2682 hydrocarbon resembling a spoked hexagonal wheel. The spokes and rim consist of phenylene-ethynylene-butadiynylene units, the core is based on hexaphenylbenzene and the phenylene groups each have two dodecyl side chains that help solubility. The molecule was constructed with a combination of Sonogashira coupling reactions (a lot of palladium and copper) and protection / deprotection reactions. Final step at a 20 mg scale.

All lab techniques thrown at the new compound supported its structure: proton NMR, MALDI-MS (mass 25,350 versus 25,260 expected), GPC (low hydrodynamic volume consistent with flattened shape). In STM the hexagons really stand out and are consistent with a 12 nm diameter. Perhaps not surprisingly this giant hydrocarbon was conceived at the Kekule-Institut in Bonn.