TY - JOUR
T1 - N,N-Dimethylaniline and 1-(trifluoromethyl)benzene-functionalized tetrakis(ethynyl)pyrenes
T2 - Synthesis, photophysical, electrochemical and computational studies
AU - Lee, Yeon Ok
AU - Pradhan, Tuhin
AU - No, Kwanghyun
AU - Kim, Jong Seung
N1 - Funding Information:
This work was supported by Sookmyung Women's University Research Grant 2009 .
PY - 2012/2/11
Y1 - 2012/2/11
N2 - We have synthesized a series of tetrakis(ethynyl)pyrenes functionalized with N,N-dimethyaniline and 1-(trifluoromethyl)benzene as a peripheral electron-donor and electron-acceptor moiety, respectively. In solvatochromic studies, compounds with one peripheral donor and three peripheral acceptors (2), with two donors and two acceptors (3 and 4), with three donors and one acceptor (5) show enhanced charge transfer compared with tetra-donor (6) and tetra-acceptor (1) compounds. The redox peak reversibility depends on the number of peripheral donors and acceptors appended to tetrakis(ethynyl)pyrenes as well as on their substitution pattern as revealed by cyclic voltammetric studies. The photophysical and electrochemical properties of compounds 1-5 have been compared with compound (6) reported recently by J.-W. Oh et al. [Angew. Chem., Int. Ed. 2009, 48, 2522-2524]. The density functional theory (DFT) based calculations such as spin density distribution (SDD) of cation/anion radicals, electrostatic potential (ESP) density distribution, non-adiabatic reduction potentials (NRP) for cation radicals, and vertical detachment energy (VDE) for anion radicals supported the experimental observations. The differences in oxidation peak reversibility for different substitution pattern have been rationalized by calculated static first hyperpolarizability (β). Our observations would be helpful in designing new ECL-active materials, where ECL (electrogenerated chemiluminescence) efficiency can be improved through improving radical stability.
AB - We have synthesized a series of tetrakis(ethynyl)pyrenes functionalized with N,N-dimethyaniline and 1-(trifluoromethyl)benzene as a peripheral electron-donor and electron-acceptor moiety, respectively. In solvatochromic studies, compounds with one peripheral donor and three peripheral acceptors (2), with two donors and two acceptors (3 and 4), with three donors and one acceptor (5) show enhanced charge transfer compared with tetra-donor (6) and tetra-acceptor (1) compounds. The redox peak reversibility depends on the number of peripheral donors and acceptors appended to tetrakis(ethynyl)pyrenes as well as on their substitution pattern as revealed by cyclic voltammetric studies. The photophysical and electrochemical properties of compounds 1-5 have been compared with compound (6) reported recently by J.-W. Oh et al. [Angew. Chem., Int. Ed. 2009, 48, 2522-2524]. The density functional theory (DFT) based calculations such as spin density distribution (SDD) of cation/anion radicals, electrostatic potential (ESP) density distribution, non-adiabatic reduction potentials (NRP) for cation radicals, and vertical detachment energy (VDE) for anion radicals supported the experimental observations. The differences in oxidation peak reversibility for different substitution pattern have been rationalized by calculated static first hyperpolarizability (β). Our observations would be helpful in designing new ECL-active materials, where ECL (electrogenerated chemiluminescence) efficiency can be improved through improving radical stability.
KW - DFT calculation
KW - Radical stability
KW - Substitution pattern
KW - Tetrakis(phenylethynyl)pyrene
UR - http://www.scopus.com/inward/record.url?scp=84855928309&partnerID=8YFLogxK
U2 - 10.1016/j.tet.2011.12.066
DO - 10.1016/j.tet.2011.12.066
M3 - Article
AN - SCOPUS:84855928309
SN - 0040-4020
VL - 68
SP - 1704
EP - 1711
JO - Tetrahedron
JF - Tetrahedron
IS - 6
ER -