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A series of donor-acceptor p-nitro-p'-alkoxy (OR) substituted (E,E,E)-1,6-diphenyl-1,3,5-hexatrienes were prepared and their properties and crystal structures investigated. The flouresence spectra of these crystals were red-shifted relative to those for the solutions in low polar solvents, which can be attributed to the planarization of molecules in the solid state and to the strong intermolecular interactions in crystals.

The change in polyene bond lengths with distance from the polyacene and the modification of the HOMO-LUMO energy gap brought about by chemisorption of the polyene on some polyacenes is presented. The conclusion states that the dispersion interactions would play a role in the interaction between planar conjugated systems.

Intramolecular Diels-Alder cycloaddition of N-substituted oxazolone triene has allowed direct entry to the functionalized octahydroquinoline. The manipulation of the framework by stereo- and regioselective introduction of the 5-methyl substituent, followed by excision of the carbamate, has produced ([plusmn])-2-epi-pumiliotoxin C.

A convenient and high-yielding three-step synthesis approach was developed to produce the simplest branched triene, [3]dendralene. The robust and operationally simple synthesis facilitated the synthesis of the volatile hydrocarbon in pure, solvent free form on a multigram scale without any involvement of chromatography, protecting groups or specialized equipment.

Study conducted shows that the solvatochromic behavior of polyenes depends on the polarizability of the medium and their solvatochromism increases markedly with increasing length of the polyene chain. The extreme sensitivity of polyenes to the polarizability of their environment is consistent with the fact that changes in molecular architecture give rise to polarizability gradients resulting in red shifts.

A novel and selective method is used for the synthesis of 8-methylenespiro[4,5]trienes via intramolecular electrophilic ipso-iodocyclization of N-(4-methylphenyl)propiolamides. Both the iodo and methylene group products obtained, provide a useful pathway to generate new groups for the synthesis of new bioactive products.

The effect of intermolecular dipole-dipole interactions on Raman spectra of polyconjugated molecules and also the behavior of push-pull polyenes are analyzed. Density functional theory (DFT) calculations are in good agreement with the mathematical models that are used for predicting the effect of intermolecular interactions on the vibrational spectra.

Intramolecular Diels-Alder reaction was used as a key step to stereoselectively synthesize coronafacic acid, a natural component of the phytotoxin coronatin. The coronafacic acid was isolated in a six-step sequence in 29% overall yield.

4-(Dimethylamino)-4'-cyano-1,4-diphenylbutadiene (DCB) and 4-(dimethylamino)-2,6-dimethyl-4'-cyano-1,4-diphenylbutadiene (DMDCB) are characterized spectroscopically. The strong difference in absorption and fluorescence solvatochromic slopes suggests that the simple Onsager model with a point dipole approximation is not sufficient.

Time-dependent Hartree-Fock theory is used to study the electronic optical response of a series of linear polyene cations (+1 and +2) in strong laser fields. For a given molecule and fixed charge state, the degree of nonadiabatic coupling and excitation is greater for geometries with lower excitation energies.

Quantitative measurements of the resonance Raman cross sections and resonance hyper-Rayleigh and hyper-Raman hyperpolarizabilities for 3[5] in dilute acetone solution are reported and computational simulations of the linear absorption, hyper-Rayleigh, resonance Raman (RR), and resonance hyper-Raman (RHR) profiles is presented. The quantitative analysis of the RR and RHR intensity, and, similarity of their spectra in the region of a single electronic resonance supports the relatively small importance of the vibrational paths.

A new example is provided of completely diastereoselective polycyclization, affording the octahydrophenanthrene framework. The carbocation is generated by anchimerically assisted regiospecific protonation of a double bond adjacent to the iron tricarbonyl diene moiety.