A German/American/Hungarian team has recently isolated hydroxymethylene (HOCH), a singletcarbene and formaldehydetautomer, although only in an argon matrix at 11 K (Schreiner et al. DOI). Ordinarily carbenes are too energetic for isolation but in this particular case the oxygen lone pair is able to provide stabilization just as in a N-heterocyclic carbene.
The researchers state that their findings are bad news for astronomers who have claimed to have spotted hydroxymethylene through their telescopes: the molecule is just too unstable.
