I've previously mentioned the TEMPO/BAIB combo for oxidising alcohols to carboxylic acid. A very smooth and mild oxidation. Back when we discussed this particular reaction we had a brief discussion about stopping this reaction at the aldehyde stage. This is indeed what this particular reaction type was developed for originally and so when I recently had to oxidise a primary alcohol to an aldehyde I thought I'd give it a go. By chance Delfourne et al. (DOI: 10.1021/jm0308702) had previously made the same compound using a TEMPO oxidation. Too easy! According to the procedure the product was obtained in quantitative yield and purification wasn't required! This particular procedure involves a crazy cocktail of reagents. This is what I did:
Fortunately, all the ingredients are reasonably affordable. Mixing it all up and adding the alcohol gives a biphasic reaction mixture that looks a bit like Schweppes Orange:
However, unlike Delfourne et al. my final product wasn't clean after a simple work up. Succinimide was simply precipitating everywhere and hence some silica was required. In the end a filtration through a silica plug proved sufficient to give clean product on a reasonably large scale (18 grams) in excellent yield (97%). So despite the fact that a simple work up wasn't sufficient to clean the product up this is an easy to do reaction that I would recommend to anyone who's tired of stinky old Swern. D!
Fortunately, all the ingredients are reasonably affordable. Mixing it all up and adding the alcohol gives a biphasic reaction mixture that looks a bit like Schweppes Orange:However, unlike Delfourne et al. my final product wasn't clean after a simple work up. Succinimide was simply precipitating everywhere and hence some silica was required. In the end a filtration through a silica plug proved sufficient to give clean product on a reasonably large scale (18 grams) in excellent yield (97%). So despite the fact that a simple work up wasn't sufficient to clean the product up this is an easy to do reaction that I would recommend to anyone who's tired of stinky old Swern. D! 
Now the above reaction is obviously totally irresponsible and was only on for less than a minute so that I could take the picture. We are dealing with a fancy piece of glassware that has oxygen bubbling through it whilst two flood lamps are hammering photons away generating singlet oxygen and in the process heating the fume hood up big time. Hence, aluminium foil on the bottom of the hood is required to 
Well at least I know it's beautiful behind all that plastic and aluminium foil. This particular day I was doing the following photolysis: 
We tend to use the bis-
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