Ethyl (2R,3R,SR)-3-(ethoxycarbonyloxy)-2-[1-(p-tolylsulfinyl) cyclopropyl]-1-pyrrolidinecarboxylate

The title compound, derived in four steps beginning with the cyclopropanation reaction of the anion of the alpha-sulfinyl ketimine (4R,SS)-4-(tert-butyldimethylsilyloxy)-3,4-dihydro-5-(p-tolysul finyl)methyl)-2H-pyrrole with 2-chloroethyl trifluoromethanesulfonate, contains a shorter than expected bond (C(7)--C(8) 1.48(l) A) and a larger than expected angle (S(1)--C(6)--C(2) 123.2(6) in the cyclopropane framework.