Structures of half-cage pentacyclododecane derivatives: skeletal deformations due to steric compression-decompression

Hexachlorinated half-cage isomer acetates may be obtained from isodrin in a cetic acid under the proper conditions and separated in highly pure form. T he X-ray crystal structure of the "inside" acetate shows that it is still m ore sterically congested than the previously reported "outside" one. Bond l engths and angles for both isomers reveal large deviations from those norma lly found in saturated systems providing interesting models for the investi gation of steric effects on chemical bonding. (C) 2000 Elsevier Science B.V . All rights reserved.