Photoinduced charge separation in zinc-porphyrin/tungsten-alkylidyne dyads: generation of reactive porphyrin and metallo radical states.
Photoinduced charge separation in zinc-porphyrin/tungsten-alkylidyne dyads: generation of reactive porphyrin and metallo radical states.
复制标题
锌-卟啉/钨-亚烷基二价体中的光致电荷分离:反应性卟啉和金属自由基态的产生。
DOI:
10.1002/chem.201303118
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发表时间:
2013
期刊:
影响因子:
--
通讯作者:
Hopkins,MichaelD
中科院分区:
文献类型:
--
作者:
Moravec,DavisB;Hopkins,MichaelD
The luminescent tungsten–alkylidyne metalloligand [WCl(≡C‐4,4′‐C6H4CC‐py)(dppe)2] (1; dppe=1,2‐bis(diphenylphosphino)ethane) and the zinc–tetraarylporphyrins ZnTPP and ZnTPClP (TPP=tetraphenylporphyrin, TPClP=tetra(p‐chlorophenyl)porphyrin) self‐assemble in fluorobenzene solution to form the dyads ZnTPP(1) and ZnTPClP(1), in which the metalloligand is axially coordinated to the porphyrin. Excitation of the porphyrin‐centered S1excited states of these dyads initiates intramolecular energy‐transfer (ZnPor→1) and electron‐transfer (1→ZnPor) processes, which together efficiently quench the S1state (∼90 %). Transient‐absorption spectroscopy and an associated kinetic analysis reveal that the net product of the energy‐transfer process is the3[dπ*] state of coordinated1, which is formed by S1→1[dπ*] singlet–singlet (Förster) energy transfer followed by1[dπ*]→3[dπ*] intersystem crossing. The data also demonstrate that coordinated1reductively quenches the porphyrin S1state to produce the [ZnPor−][1+] charge‐separated state. This is a rare example of the reductive quenching of zinc porphyrin chromophores. The presence in the [ZnPor−][1+] charge‐separated states of powerfully reducing zinc–porphyrin radical anions, which are capable of sensitizing a wide range of reductive electrocatalysts, and the1+ion, which can initiate the oxidation of H2, produces an integrated photochemical system with the thermodynamic capability of driving photoredox processes that result in the transfer of renewable reducing equivalents instead of the consumption of conventional sacrificial donors.
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影响因子:
4.4
作者:
Bazan,HE;Birkle,DL;Beuerman,R;Bazan,NG
通讯作者:
Bazan,NG
影响因子:
2
作者:
Bazan,HE;King,WD;Rossowska,M
通讯作者:
Rossowska,M
DOI:
10.1001/archopht.1981.03930011085020
发表时间:
1981
期刊:
Archives of ophthalmology (Chicago, Ill. : 1960)
影响因子:
--
作者:
Srinivasan,BD;Kulkarni,PS
通讯作者:
Kulkarni,PS
影响因子:
3.4
作者:
L. Bito
通讯作者:
L. Bito
影响因子:
3.4
作者:
Williams,RN;Paterson,CA
通讯作者:
Paterson,CA