Convergent synthesis of 10 nm aryleethynylene molecular wires by an iterative regioselective deprotection/sonogashira coupling protocol

Wang, C.; Batsanov, A.S.; Bryce, M.R.

Abstract

The synthesis of a new series of rigid-rod aryleneethynylene derivatives of up to ca. 10 nm molecular length (compounds 16 and 17) is reported using iterative Pd-mediated Sonogashira coupling methodology combined with regioselective removal of the different protecting groups (namely, trimethylsilyl and 2-hydroxyprop-2-yl groups) from the terminal alkyne units. Additionally, the TMS-acetylene unit has been cleanly deprotected to afford a terminal alkyne in the presence of a cyanoethylsulfanyl group. Some of these molecular wires are functionalized with terminal protected thiophenol units for attachment to metal surfaces (compounds 16 and 17). Internal electron-acceptor units have been incorporated into their structures, namely, 9-[di(4-pyridyl)methylene]fluorene (compound 17) or fluorenone (compounds 19-22). Optical absorption and photoluminescence spectra reveal a red shift in the value of max with increasing molecular length, which approaches saturation at an effective conjugation length of ca. 15-20 -units in the molecules, where each phenyl ring or a triple bond is counted as one -unit.

Citation

Wang, C., Batsanov, A., & Bryce, M. (2006). Convergent synthesis of 10 nm aryleethynylene molecular wires by an iterative regioselective deprotection/sonogashira coupling protocol. Journal of Organic Chemistry, 71(1), 108-116. https://doi.org/10.1021/jo051711o

• Journal Article Type: Article
• Publication Date: 2006-11
• Deposit Date: Apr 25, 2007
• Journal: Journal of Organic Chemistry
• Print ISSN: 0022-3263
• Electronic ISSN: 1520-6904
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 71
• Issue: 1
• Pages: 108-116
• DOI: https://doi.org/10.1021/jo051711o
• Public URL: https://durham-repository.worktribe.com/output/1542623