A spoonful of sugar makes the catalytic activity go down! [Dalton Trans.]

I’m delighted to finally publish this work, the first of my research carried out during my Marie Curie Fellowship in University of Bern to come out. A lot of hard work by Erasmus student Pauline went into gathering data behind this manuscript where we asked the question – what impact would incorporating carbohydrates into the structure of a Ruthenium(II)-triazolylidene complex have on its ability to convert a ketone to an alcohol via transfer hydrogenation catalysis.

There were challenges in isolating the desired compound, so it had to be generated in situ, but we were able to assess the activity, and the results were interesting, and can be found in detail here in Dalton Transactions.

To summarise the conclusions: The carbohydrate functionality does impact catalytic activity (transfer hydrogenation of ketones). In complexes with the glucose directly triazolylidene-bound,  turnover rates were substantially higher when compared to more remote carbohydrate functionalisation (i.e. with an ethylene spacer). Both new complexes, however, have reduced activity compared to  unfunctionalised carbene complexes. Insight was also gained into the nature of the catalytic cycle through a substrate scope analysis.

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The Gurten – my local “mountain”

I like hiking – or at least, I did in Ireland. A look to the scenery all around me in Switzerland suggests that my understanding of the word “hike” may need an upgrade. The Wicklow “Mountains” where I so often wandered with friends and colleagues are only foothills on the scale of the Alps. The Great Sugarloaf (An Beannach Mór), the pointy quartzite cone visible from anywhere high in Dublin or Wicklow is a mere 500 metres at its summit, and I considered that a considerable day out!

The Great Sugarloaf and me in 2014
The Great Sugarloaf and me in 2014

With nothing else planned for my third Saturday here, my new co-worker was interested in an outdoor activity, so we met at the train station and walked up the Aare River (which I had only seen briefly to date) southwards out of town. It was a decent trek to the base of the mountain, but it was a fine sunny day and I was keen to explore my new home.

Eventually coming to the tram stop where a lazier adventurer would have started, we ignored the cool retro furnicular which climbed the slope of the hill on mechanisms of cogs and rope. I should, of course, say “mountain”. It’s 858 metres at the peak – that beats anything I’ve done before, I think.IMG_7209 IMG_7211

It was a steep climb up the wooded path. We were, however, constantly being passed out by infuriatingly fit old Swiss people zooming up and down the slope. Everyone is fit here – I suppose that’s what they all do on Sundays when the city becomes eerily quiet and empty. If not, they’d all just be hiding indoors. With this scenery on your doorstep, why wouldn’t you be hiking or climbing or skiing? We were treated with occasional glances back up the river to the Old City of Bern which is a UNESCO World Heritage Site.

Altstadt Bern
Altstadt Bern

Anyway, we reached the top of the mountain, turned left and the scene opened out – I looked out over the vista and saw the Alps in the distance, straddling the horizon… so that’s what a mountain looks like! I mean, they’re really big. Still snow-capped into Spring, despite the sun. Jungfrau mountain in the distance (for comparison to our paltry examples) is a whopping 4158 metres high! The peaks were away over the rolling green manicured lawns of the park on top of Gurten.  It’s truly an idyllic scene.

The Bernese Oberland
The Bernese Oberland from the top of Gurten

We strolled around the top, stumbling upon a meadow, full of dandelions and other wildflowers; it was a Sound of Music moment. In the distance, across the valley, the sound of cowbells drifted across on the air as a herd wandered on the far slope. They made quite the noise with only a few cowbells, I can only imagine the din if there were more cowbell [I couldn’t resist].

"What a lovely meadow!"
“What a lovely meadow!”

Suitably put in my place by my new understanding of what “tall” means, we wandered back by the river Aare and saw the local celebrities, the Bernese Bears, just waking up from hibernation. They’ve been moved out of their pit into a very pleasant and spacious environment.

The bear in Bern having a kip
The bear in Bern having a kip

I’m living in a nice country now! Plenty of peaks to attempt, although I may have to be more satisfied with shoulders going forward.