The syntheses,spectra, and some reactions of 2-phthalimidyl- and 2-phthalimidyl-4.5-dichloro-5-azabicyclo[2.1.0]pentane

Cyclobutene has been prepared by an improved method. The reaction ofN-aminophthalimide with cyclobutene or cis-3,4-dichlorocyclobutene in the presence of lead tetraacetate gives 2-phthalimidyl- (5) or 2-phthalimidyl-4,5-dichloro-5-azabicyclo2.1.0]pentane (6), respectively. The NMR spectra of 6 showed the presence of exo (9) and endo (10) isomers. The effect of ring size on the chemical shift of the bridgehead hydrogen absorption in a series of azabicyclon.1.0]alkanes was examined. Several reactions of 5 and 6 and alternative syntheses of the azabicyclo2.1.0]pentane system were investigated.