Novel pentafulvalene derivatives: synthesis, crystal structures, 1H and 13C NMR chemical shift assignments of trans- and cis-isomers of bis-2,2′-(4,5,6,7-tetrachloro-8,8-dimethoxy- 3a,4,7,7a-tetrahydro-4,7-methanoindan-1,3a-dienylidene)
Abstract
Synthesis, single crystal structures, 1H and 13C NMR chemical shift assignments based on z-gradient selected (z-GS) heteronuclear multiple quantum coherence (1HC HMQC) and heteronuclear multiple bond correlation (1HC HMBC)experiments are given for novel pentafulvalene derivatives, trans-and cis-isomers of bis-2,2′-(4,5,6,7-tetrachloro-8,8-dimethoxy-3a,4,7,7a-tetrahydro-4,7-methanoindan-1,3a-dienylidene), 1 and 2, derived from 1-exo-2-endo-3-exo-4,5,6,7,8,8-nonachloro-3a,4,7,7a-tetrahydro-4,7-methanoindane (trans-nonachlor) by treatment with sodium methoxide.