Diels–Alder cycloadditions of stabilised 2,3-pyridynes

Investigation of electron donating substituents at C-4 on 2,3-pyridyne 1 stability has revealed a novel stabilisation of these reactive species by aryloxy and thiophenoxy groups leading to a relatively high yielding [4+2] cycloaddition between 4-(p-methoxyphenoxy)-2,3-pyridyne and furan at low temperature.