Synthesis of spiro pyrrolidines via formal [3+2] cycloaddition of unusual enones and cis-3-benzoyl-1-cyclohexyl-2-phenylaziridine

The synthesis of a new class of spiro[tetrahydronaphthalen-one/butenolide]pyrrolidines has been accomplished by the 1,3-dipolar cycloaddition of azomethine ylide generated by thermal ring opening of cis-3-benzoyl-1-cyclohexyl-2-phenylaziridine with (E)-2-arylidene-1,2,3,4-tetrahydronaphthalen-1-ones and (E)-3-arylidene-5-phenyl-Δ4,5-butenolides. The structures of the products were confirmed by spectroscopic techniques as well as single crystal X-ray analysis of one of the products.