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arXiv · 1011.3657

Synthesis, Characterization, and Modeling of Naphthyl-Terminated sp Carbon Chains: Dinaphthylpolyynes

Franco Cataldo·Luca Ravagnan·Eugenio Cinquanta·Ivano Eligio Castelli·Nicola Manini·Giovanni Onida·Paolo Milani
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Abstract

We report a combined study on the synthesis, spectroscopic characterization and theoretical modelling of a series of α,ω-dinaphthylpolyynes. We synthesized this family of naphtyl-terminated sp carbon chains by reacting diiodoacetylene and 1-ethynylnaphthalene under the Cadiot-Chodkiewicz reaction conditions. By means of liquid chromatography (HPLC), we separated the products and recorded their electronic absorption spectra, which enabled us to identify the complete series of dinaphthylpolyynes Ar-C2n-Ar (with Ar = naphthyl group and n = number of acetilenic units) with n ranging from 2 to 6. The longest wavelength transition (LWT) in the electronic spectra of the dinaphthylpolyynes red shifts linearly with n away from the LWT of the bare termination. This result is also supported by DFT-LDA simulations. Finally, we probed the stability of the dinaphthylpolyynes in a solid-state precipitate by Fourier-transform infrared spectroscopy and by differential scanning calorimetry (DSC).

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Franco Cataldo, Luca Ravagnan, Eugenio Cinquanta, Ivano Eligio Castelli, Nicola Manini, Giovanni Onida, Paolo Milani. 2010-11-16. Synthesis, Characterization, and Modeling of Naphthyl-Terminated sp Carbon Chains: Dinaphthylpolyynes. https://doi.org/10.1021/jp104863v

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