A class of alkylating agents including carboquone 
A class of alkylating agents including carboquone and ThioTEPA contain this functionality, which can be synthesized from vinyl dihalides and DBU in a reaction named for Cromwell and Gabriel. One method of synthesizing these compounds involves the [3+2] addition of a guanidinium ylide to carbonyl compounds. Leighton and Rhenquist modified one important method of synthesizing these compounds by lowering the temperature and adding glass beads, while another method was modified to use LiAl4 instead of a Grignard reaction. That method has an "intermolecular trapping" variant developed by Taguchi and begins with a ketoxime, known as the Hoch-Campbell reaction. A more popular method of synthesizing them uses sulfuric acid on a beta-amino alcohol, known as the Wenker synthesis. Like a related class of compounds, they have very high ring strain, making them susceptible to nucleophilic attack. For 10 points, name these nitrogen-containing three-member rings, the aza variants of epoxides.
A class of alkylating agents including carboquone and ThioTEPA contain this functionality, which can be synthesized from vinyl dihalides and DBU in a reaction named for Cromwell and Gabriel.
{Aziridines} (accept {ethenylamines})