Nitrogen analogues of Chichibabin's and Müller's hydrocarbons with small singlet–triplet energy gaps

Nitrogen analogues of Chichibabin's and Müller's hydrocarbons exhibit small singlet–triplet energy gaps (ΔES–T from −1.05 to −1.27 kcal mol−1).

DFT exploration of [3 + 2] cycloaddition reaction of 1H-phosphorinium-3-olate and 1-methylphosphorinium-3-olate with methyl methacrylate

These phosphorus cycloadducts are kinetically and thermodynamically more favorable than their nitrogen analogues, providing incentives to experimentalists in the quest to synthesise phosphorus containing heterocycles.