Cyclic tetramers of optically active aziridines: 1,4,7,10-tetrabenzyl-2,5,8,11-tetra-(R)-ethyl-1,4,7,10-tetraazacyclododecane

Stable organic cation salts: Ion pair equilibria and use in cationic polymerisation

“…Presumably the explanation lies in the stereochemistry of the system since this particular monomer is the only carbon substituted species. Even more strangely, however, the closely related molecule 1-benzyl-2-ethyl-aziridine is reported (141) to behave like 8, 9, and 10 when treated with boron trifluoride. In the case of the parent molecules aziridine (117) and azetidine (t42), polymerisations are complicated because the protons of the active species tend to distribute themselves among the nitrogen atoms of different types present in the reaction mixture, according to their base strengths.…”

Imines, Cyclic

“…Spherical starburst dendrimers, which contain tertiary amino groups on the inside and primary amino groups on the surface, are obtained by repeating this synthesis sequence several times (360). The reaction of 1-alkylaziridines, in particular 1-benzylaziridines, with catalytic amounts of acids in ethanol leads to the formation of cyclic oligomers, which are normally composed of four aziridine units (361)(362)(363).…”

The structure of (2R,5S,8R,11S)-1,4,7,10-tetrabenzyl-2,5,8,11-tetraethyl-1,4,7,10-tetraazacyclododecane

“…© 1981 International Union of Crystallography In the presence of BF3.Et20, (R)-l-benzyl-2-ethylaziridine (1) reacts to give a cyclic tetramer (2) or the corresponding polymer depending on the reaction conditions (Tsuboyama, Tsuboyama, Higashi & Yanagita, 1970). Only one isomer of the tetramer was found, which means that the ring cleavage of the aziridine takes place preferentially at the methylene-nitrogen linkage.…”