Two Dyotropomers Resulting from Irreversible Thermal (4σ+2π) 2H Group Transfer

The structures of two compounds, (1D) (endo-endo-1,5,6,7,8,12,13,14,15, 15-decachloropentacyclo-[10.2.1.1 3,10 .0 2,11 .0 4,9 ]hexadeca4(9),5,7-triene, C 16 H 8 Cl 10 ) and (2D) (13,14-benzo-3,4,5,6-tetrachlorotetracyclo-[6.4.2.2 9,12 .0 2,7 ]hexadeca-2(7),3,5-triene, C 20 H 16 Cl 4 ), are reported. Both compounds are products of an irreversible dyotropic rearrangement where two H atoms are transferred intramolecularly onto a proximate π bond. These compounds are two members of several different series of compounds being studied with the aim of understanding the factors affecting the rate of this type of 2H group-shift isomerization which can vary enormously with changes in the substitution pattern at, or near, the reaction zone. The atom-numbering system used for compounds of series (I) is that of Mackenzie et al. [Tetrahedron (1987), 43, 5981-5993]. [The systematic name of (1D) using IUPAC nomenclature is endo-endo-3,4,5,6,10,11,12,13,16,16-decachloropentacyclo[6.6.1.1 3,6 .0 2,7 .0 9,14 ]hexadeca-9(14),10,12-triene.]