Proton magnetic resonance studies of compounds with bridgehead nitrogen. Part 35. The 5-t-butylperhydropyrido[1,2-c][1,3,7]oxadiazonine ⇌ 10,22-di-t-butylperhydrodipyrido[1,2-c:1,2-I]-1,10-dioxa-3,7,12,16-tetrazacyclodecine ⇌ 2-t-butyl-2-β-hydroxyethylperhydropyrido[1,2-c]pyrimidinium equilibrium

Abstract

The reaction between 2-(N-β-hydroxyethyl-N-β-t-butylaminoethyl)piperidine and formaldehyde gives the crystalline dimeric 10,22-di-t-butylperhydrodipyrido[1,2-c:1,2-I]-1,10-dioxa-3,7,12,16-tetrazacyclodecine. In chloroform solution this compound rapidly comes into equilibrium with 5-t-butylperhydropyrido[1,2,-c][1,3,7]oxadiazonine and the 2-t-butyl-2-β-hydroxyethylperhydropyrido[1,2-c]pyrimidinium ion. Evaporation of the chloroform followed by crystallisation of the residual oil gives the crystalline dimer.