Chemical reactions of cycloalkanespirohydantoins. Part 3. Acid‐catalyzed reaction of 4‐hydroxy‐2‐imidazolidinones. Preparation of bis(1,3‐diaza‐2‐oxospiro[4,5]decyl‐4) ether

1. Pedregal, C.
2. Espada, M.
3. Salazar, L.
4. Elguero, J.