The synthesis of bichromophoric rigid norbornylogous systems containing the porphyrin group as one of the chromophores

Abstract

The synthesis of three novel systems in which the porphyrin group is fused to a norbornyl unit, or to an extended linearly fused system of norbornyl and bicyclo[2.2.2]octyl units, is described. The compounds are: 7,10,13,16-tetraphenyl-1,2,3,4-tetrahydro-1,4-ethanobenzo[g]quinoxalino[2,3-b]porphyrin (7a), 1,4-imethoxy-8,11,14,17-tetraphenyl-5,20-dihydro-5,20-methanonaphtho-[2,3-g]quinoxalino[2,3-b] porphyrin (3), and (5α,5aβ,5bα,5cβ,6α,21α,21 aβ,21bα,21cβ,22α)-1,4-dimethoxy-5b,21b-dimethyl-9,12,15,18-tetra phenyl-5,5a,5c,6,21,21 a,21c,22-octahydro-5,22:6,21-dimethanonaphtho [2‴,3‴ : 3″,4″] cyclobuta [1″,2″ : 3′,4′] cyclobuta [1′,2′ : 4,5] benzo[1,2-g]quinoxalino[2,3-b]porphyrin (4). In each case, the porphyrin unit is linked to the norbornyl ring through a quinoxaline group, and this was formed through condensation of 17,18-dioxo-5,10,15,20-tetraphenylchlorin (6) and the appropriate norbornyl-o-phenylenediamine (5d), (22a), or (22b).