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-1,2,3,4tetra hydro-1,4-methanobenzo [g] quinoxalino [2,3b] porphyrin (7a),

A New Class of Giant Tetrads for Studying Aspects of Long-Range Intramolecular Electron Transfer Processes: Synthesis and Computational Studies

“…(Table 1) are similar to those of the model compound 24 (to within 0.2 ppm) and show no evidence of any shielding by the porphyrin ring current. [14] Dilution experiments (10 À2 to 10 À5 m, CDCl 3 ) resulted in no observable changes in the 1 H NMR spectrum of syn,syn-19, nor did its electronic spectrum (in CHCl 3 ) show any deviation from the Beer ± Lambert law. [14] Dilution experiments (10 À2 to 10 À5 m, CDCl 3 ) resulted in no observable changes in the 1 H NMR spectrum of syn,syn-19, nor did its electronic spectrum (in CHCl 3 ) show any deviation from the Beer ± Lambert law.…”

“…Synthesis: The synthesis of 6 (Scheme 4) was achieved by using the procedures reported by Antolovich et al: [14] condensation of the diamine 10, [14] prepared from 12 in 10 steps, with the porphyrin-dione 11 [31] in CH 2 Cl 2 resulted in the formation of the porphyrin 13 as a red solid in excellent yield. Treatment of 13 with BBr 3 gave the hydroquinone in 85 % yield.…”

“…[1] Many different hydrocarbon bridges have been employed [2] in ET studies, including steroid-based systems, [1a, 3] cyclohexane and decalin, [4] oligobicyclo [2.2.2]octanes, [5] tripty-cenes, [6] polyspirocyclobutanes, [7] and norbornylogous bridge systems comprising linearly fused norbornane and bicyclo [2.2.0]hexane units, [8] such as 1 and 2. A wide range of different chromophores may be easily attached to the termini of the norbornylogous bridge, for example naphthalene [10] and anthracene rings, [11] pyridazines, [12] pyridines, [13] quinones, [14] tetracyanonaphthoquinones, [15] porphyrins, [14,16] diones, [17] dipyridyls, [18] and even the C 60 cage. [1b, 8] The norbornylogous bridge has two important advantages over most of the other types of hydrocarbon bridges that have been used for ET studies.…”

Synthetic Chemistry of Quadricyclane

“…The cycloaddition of 1,4,5,8-naphtoquinone (67) to Q proceeds through central double bond leading to adduct 68 [56]. …”

“…Due to high regioselectivity and flexibility this methodology was employed for the synthesis of variety extended, rigid, rod-like norbornylogous molecules, similar to 94 or 96 [63,[65][66][67][68][69][70].…”