Dicopper(I) Complexes Incorporating Acetylide-Functionalized Pyridinyl-Based Ligands: Synthesis, Structural, and Photovoltaic Studies

Maharaja Jayapal; Ashanul Haque; Idris J Al-Busaidi; Nawal Al-Rasbi; Mohammed K Al-Suti; Muhammad S Khan; Rayya Al-Balushi; Shahidul M Islam; Chenghao Xin; Wenjun Wu; Wai-Yeung Wong; Frank Marken; Paul R Raithby

doi:10.1021/acs.inorgchem.8b01684

Dicopper(I) Complexes Incorporating Acetylide-Functionalized Pyridinyl-Based Ligands: Synthesis, Structural, and Photovoltaic Studies

Inorg Chem. 2018 Oct 1;57(19):12113-12124. doi: 10.1021/acs.inorgchem.8b01684. Epub 2018 Sep 17.

Authors

Affiliations

¹ Department of Chemistry , Sultan Qaboos University , P.O. Box 36, Al Khod 123 , Sultanate of Oman.
² Department of Basic Sciences, College of Applied and Health Sciences , A'Sharqiyah University , Ibra 400 , Sultanate of Oman.
³ Department of Chemistry , University of Illinois at Chicago , Chicago , Illinois 60607 , United States.
⁴ Key Laboratory for Advanced Materials and Institute of Fine Chemicals, Centre for Computational Chemistry, Shanghai Key Laboratory of Functional Materials Chemistry, School of Chemistry and Molecular Engineering , East China University of Science and Technology , Shanghai 200237 , China.
⁵ Institute of Molecular Functional Materials and Department of Applied Biology and Chemical Technology , The Hong Kong Polytechnic University , Hung Hom , Kowloon , Hong Kong.
⁶ Department of Chemistry , University of Bath , Claverton Down , Bath BA2 7AY , U.K.

PMID: 30222331
DOI: 10.1021/acs.inorgchem.8b01684

Abstract

Heteroaryl incorporated acetylide-functionalized pyridinyl ligands (L1-L6) with the general formula Py-C≡C-Ar (Py = pyridine and Ar = thiophene-2-yl, 2,2' -bithiophene]-5-yl, 2,2' :5',2″ -terthiophene]-5-yl, thieno[2,3- b]thiophen-2-yl, quinoline-5-yl, benzo[c][1,2,5]thiadiazole-5-yl) have been synthesized by Pd(0)/Cu(I)-catalyzed cross-coupling reaction of 4-ethynylpyridine and the respective heteroaryl halide. Ligands L1-L6 were isolated in respectable yields and characterized by microanalysis, IR spectroscopy, ¹H NMR spectroscopy, and ESI-MS mass spectrometry. A series of dinuclear Cu(I) complexes 1-10 have been synthesized by reacting L1-L6 with CuI and triphenylphosphine (PPh₃) (R1) or with an anchored phosphine derivative, 4-(diphenylphosphino) benzoic acid (R2)/2-(diphenylphosphino)benzenesulfonic acid (R3), in a stoichiometric ratio. The complexes are soluble in common organic solvents and have been characterized by analytical, spectroscopic, and computational methods. Single-crystal X-ray structure analysis confirmed rhomboid dimeric structures for complexes 1, 2, 4, and 5, and a polymeric structure for 6. Complexes 1-6 showed oxidation potential responses close to 0.9 V vs Fc^0/+, which were chemically irreversible and are likely to be associated with multiple steps and core oxidation. Preliminary photovoltaic (PV) results of these new materials indicated moderate power conversion efficiency (PCE) in the range of 0.15-1.56% in dye-sensitized solar cells (DSSCs). The highest PCE was achieved with complex 10 bearing the sulfonic acid anchoring functionality.