Optical and thermal electron transfer in rigid difunctional molecules of fixed distance and orientation

Synthesis and crystal structures of three rigidly linked donor–acceptor systems designed to test the effect of bridge configuration on the dynamics of long-range intramolecular electron transfer processes

“…30 The torsional angles for the C-C bonds in the relays of 3-4 clearly reveal the degree of deviation from the optimal all-trans (antiperiplanar) alignments required to maximise throughbond interactions (Table 7). Thus, the absolute values of the torsional angles for trans arrangements of bonds in 3 and 4, such as C(9)-C(8)-C(7kC (6) in 3, are greater than 173" and are therefore close to the idealized antiperiplanar value of 180". This was also found in the crystal structures for 1 and 2."…”

Electron‐transfer Organic and Bioorganic Photochemistry

“…These compounds reveal the emission from the electron-transfer excited state. Analyses of the emissive electrontransfer process showed large through-bond coupling between the chromophores, which was indeed approved by the optical electron-transfer spectra of the anion radical (Penfield et al, 1987). Effects of through-bond coupling on the intramolecular electron transfer of these particular compounds have been reviewed from theoretical points of view and from experimental and mechanistic aspects (Miller, 1987).…”

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

“…Column chromatography of the residue (silica, CH,Cl,) gave (20a) (0. (3).-A solution of (20a) (0.5 g, 1 mmol) in hydrazine hydrate (85%, 12 cm3) was heated at 70°C for 17 h. Most of the hydrazine hydrate was removed under reduced pressure and the residue was dissolved in CH2C12 (30 cm3) and washed with water (2 x 15 cm3). The organic layer was dried and evaporated to give crude (21a) (0.4 g, 87%) which was not purified further; 6"(500 ll-H),3.84(3H,s,OCH,),3.85(3H,s,OCH3),4.5O(1 H,s,9-or 10-H), 4.53 (1 H, s, 9-or 10-H), 6.33 (2 H, v br s, NH2), 6.81 (1 H, s, 5-H), and 7.97 (1 H, s, 8-H).…”