Micro- and macro-scopic second-order non-linear optical properties of fulvene compounds

Abstract

A number of fulvene compounds, which can polarize to give rise to intramolecular charge transfer (ICT), have been synthesized, and the second-order molecular hyperpolarizability (p) and dipole moment (,uJ have been calculated by using the MOPAC program. The macroscopic non-linearity (second-harmonic generation; SHG) evaluated by the Kurtz powder method is discussed in relation to microscopic p and pg. The large p and the small p g are characteristic of these compounds and contribute to the SHG activity. Among these compounds, co-(pmethoxypheny1)benzofulvene (MPBF) was found to exhibit large SHG activity and could be grown into large crystals. X-Ray diffraction analysis of MPBF shows non-centrosymmetrically cylindrical packing along the b-axis. The effective non-linear optical coefficient d,, of MPBF, which was evaluated from the bulk crystal cut to the phase-matching direction, corresponds to the value (7.0 pm V-') of potassium titanylphosphate (KTP), although the hardness is low (24 Vickers hardness).

Synthesis of selectively deuterated fulvenes and indenes from enediynes

“…Interest in substituted fulvenes and benzofulvenes stems from their potential as building blocks for the preparation of metallocene catalysts, 1 and from the application of fulvenes as electron acceptors in material science and molecular electronics. 2 Fulvenes and benzofulvenes have also been used as key intermediates in the total synthesis of several natural products and patented as anti-inflammatory agents having antipyretic and analgesic activity. 3 Deuterated indenes have received significant attention as mechanistic probes, e.g., in Clemmensen reduction, 4 photochemistry of alkylindenes, 5 hydrogenolysis, 6 rutheniummediated cycloaromatization, 7 etc.…”

(3-Chlorophenyl){2-ethoxy-5-[(Z)-hydroxy(phenyl)methylidene]cyclopenta-1,3-dien-1-yl}methanone

“…Fulvenes also raised interest due to their potential as non-linear optic materials (Kondo et al 1992).…”

“…For complexes based on 2-acyl-6hydoxyfulvenes, see: Dong et al (2004Dong et al ( , 2006; Wang et al (2005). For their various applications, see: Hong et al (2005); Kondo et al (1992); Vicente et al (1995). Hydrogen-bond geometry (Å , ).…”

Predicting reduction potentials of 1,3,6‐triphenyl fulvenes using molecular electrostatic potential analysis of substituent effects

“…Pentafulvenes, structural isomers of benzene, have received significant attention owing to their unique reactivity. They are having a broad range of applications varying from natural products to semiconductors . Ottosson et al demonstrated that the CC exocyclic bond in polyfulvene can act as a handle, through which electronic and geometric structures can be tuned with substituents.…”