TY - JOUR AU - Iwanaga, Tetsuo; Yamamoto, Yuta; Nishioka, Keita; Toyota, Shinji TI - Efficient Synthesis and Electronic Spectra of Unsymmetrical 5,12-Diethynyltetracene Derivatives SN - 0039-7881 SN - 1437-210X PY - 2015 JO - Synthesis JF - Synthesis LA - EN VL - 47 IS - 24 SP - 3997 EP - 4007 ET - 2015/09/16 DA - 2015/12/07 KW - tetracene KW - ethynyllithium KW - one-pot process KW - Sonogashira coupling KW - electronic spectrum AB - Unsymmetrical 5,12-diethynyltetracene derivatives were synthesized from tetracenequinone by the addition of two types of ethynyllithium reagents, followed by reductive aromatization with SnCl2­. These three-step reactions could be integrated into a one-pot process to give unsymmetrically substituted 5,12-diethynyltetracene derivatives in moderate yields. Some unsymmetrical 5,12-bis(phenylethynyl)tetracene derivatives were synthesized from 5-ethynyl-12-phenylethynyltetracene and iodobenzenes by Sonogashira coupling. This integrated process was applied to the synthesis of a π-extended tetracene dimer. The photophysical properties of these compounds were examined by UV/Vis and fluorescence spectroscopy. PB - © Georg Thieme Verlag DO - 10.1055/s-0035-1560474 UR - http://www.thieme-connect.com/products/ejournals/abstract/10.1055/s-0035-1560474 ER -