التفاصيل البيبلوغرافية
| العنوان: |
Sterically Encumbered Heteroleptic Copper(I) β-Diketiminate Complexes with Extended Excited-State Lifetimes. |
| المؤلفون: |
Kim D; Department of Chemistry, University of Houston, Houston, Texas 77204-5003, United States., Rosko MC; Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States., Dang VQ; Department of Chemistry, University of Houston, Houston, Texas 77204-5003, United States., Castellano FN; Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States., Teets TS; Department of Chemistry, University of Houston, Houston, Texas 77204-5003, United States. |
| المصدر: |
Inorganic chemistry [Inorg Chem] 2023 Oct 16; Vol. 62 (41), pp. 16759-16769. Date of Electronic Publication: 2023 Oct 02. |
| نوع المنشور: |
Journal Article |
| اللغة: |
English |
| بيانات الدورية: |
Publisher: American Chemical Society Country of Publication: United States NLM ID: 0366543 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1520-510X (Electronic) Linking ISSN: 00201669 NLM ISO Abbreviation: Inorg Chem Subsets: MEDLINE |
| أسماء مطبوعة: |
Original Publication: [Easton, Pa.] American Chemical Society. |
| مستخلص: |
One of the main challenges in developing effective copper(I) photosensitizers is their short excited-state lifetimes, usually attributed to structural distortion upon light excitation. We have previously introduced copper(I) charge-transfer chromophores of the general formula Cu(N^N)(ArNacNac), where N^N is a conjugated diimine ligand and ArNacNac is a substituted β-diketiminate ligand. These chromophores were promising regarding their tunable redox potentials and intense visible absorption but were ineffective as photosensitizers, presumably due to short excited-state lifetimes. Here, we introduce sterically crowded analogues of these heteroleptic chromophores with bulky alkyl substituents on the N^N and/or ArNacNac ligand. Structural analysis was combined with electrochemical and photophysical characterization, including ultrafast transient absorption (UFTA) spectroscopy to investigate the effects of the alkyl groups on the excited-state lifetimes of the complexes. The molecular structures determined by single-crystal X-ray diffraction display more distortion in the ground state as alkyl substituents are introduced into the phenanthroline or the NacNac ligand, showing smaller τ 4 values due to the steric hindrance. UFTA measurements were carried out to determine the excited-state dynamics. Sterically encumbered Cu5 and Cu6 display excited-state lifetimes 15-20 times longer than unsubstituted complex Cu1 , likely indicating that the incorporation of bulky alkyl substituents inhibits the pseudo-Jahn-Teller (PJT) flattening distortion in the excited state. This work suggests that the steric properties of these heteroleptic copper(I) charge-transfer chromophores can be readily modified and that the excited-state dynamics are strongly responsive to these modifications. |
| تواريخ الأحداث: |
Date Created: 20231002 Latest Revision: 20231031 |
| رمز التحديث: |
20231031 |
| DOI: |
10.1021/acs.inorgchem.3c02042 |
| PMID: |
37782937 |
| قاعدة البيانات: |
MEDLINE |
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