Woolhouse had previously examined the addition of phenyl azide to 7a to give 8a (Ar= C6H5) and the subsequent pyrolysis and photolysis of this triazoline. 6b They found that while the 1J-dipolar addition offered no problems, both pyrolysis and photolysis gave only the exo aziridine, 10a (Ar= C&). We were able to confirm the general findings of Halton and Woolhouse on 7a. In the initial part of our investigation, we utilized p-nitrophenyl axide ...