DOI: 10.1002/chem.201301630 Assembling a Phthalocyanine and Perylenediimide Donor–Acceptor Hybrid through a Platinum(II) Diacetylide Linker ngel J. JimØnez, [a] Michael Sekita, [b] Esmeralda Caballero, [a] M. Luisa Marcos, [c] M. SalomØ Rodríguez-Morgade, [a] Dirk M. Guldi,* [b] and Tomµs Torres* [a, d] Dedicated to Professor Asland Yusupovich Tsivadze on the occasion of his 70 th birthday Introduction In the last few decades the development of artificial photo- synthetic systems mimicking the natural process for solar- energy conversion and exploitation of molecular devices has attracted great interest. [1, 2] An important approach to ach- ieve this goal is the development of new electron donors and electron acceptors linked by well-defined spacers. [3, 4] The role played by spacers is not only structural, as its chemical nature governs the electronic communication be- tween the electron donors/electron acceptors. Another val- uable asset of spacers is their modular composition, which allows fine-tuning of the spatial separation with or without affecting the electronic nature of the connection. Synthetic analogues of porphyrins, such as phthalocya- nines (Pcs), feature remarkably high extinction coefficients in the wavelength range of around 700 nm. [5] In fact, Pcs have emerged as excellent light-harvesting antennas and have been incorporated into electron donor–acceptor conju- gates and hybrids, especially for light harvesting in the red part of the solar spectrum. [6, 7] On the other hand, perylene- diimides (PDIs) have been established as an oxidizing com- plement to Pcs en route towards conjugates and/or hybrids that reveal energy transfer and/or electron transfer in the form of long-lived radical ion-pair states. [8, 9] Recently, we have synthesized a covalently linked Pc- PDI-Pc conjugate that was shown to be electronically cou- pled in the ground state. [9a] In this hybrid, two ZnPc rings were connected to the bay region of a PDI by means of triple bonds. Furthermore, we have studied the trans-plati- num(II) diacetylide moiety as a linker of Pc subunits in Zn II phthalocyanine dimers (Pc-Pt-Pc). [10] Insertion of such a s-bonded spacer between two Pcs decouples the two macro- cycles from each other and induces, through a heavy atom effect, fast intersystem crossing for the singlet excited state to triplet excited state. There are very few examples in which the platinum diacetylide bridge is used to attach donor and acceptor electroactive units, [11, 12] and even fewer [11a, 12] are designed for photoinduced electron transfer. In the current work, we have prepared and studied a Pc-Pt- PDI conjugate 1 by connecting a ZnPc to the bay region of a PDI derivative through a platinum(II) diacetylide linker. By doing so, we expected to achieve deceleration of the charge recombination, that is, decay of the photolytically generated radical ion-pair state, by means of 1) the electron- [a] Dr. . J. JimØnez, Dr. E. Caballero, Dr. M. S. Rodríguez-Morgade, Prof. T. Torres Departamento de Química Orgµnica (C-1) Universidad Autónoma de Madrid Cantoblanco, 28049 Madrid (Spain) Fax: (+ 34) 91-397-3966 E-mail: tomas.torres@uam.es [b] M. Sekita, Prof. Dr. D. M. Guldi Department of Chemistry and Pharmacy Interdisciplinary Center for Molecular Materials (ICMM) University of Erlangen-Nuremberg Egerlandstrasse 3, 91058 Erlangen (Germany) Fax: (+ 49) 9131-852-8307 E-mail : dirk.guldi@chemie.uni-erlangen.de [c] Dr. M. L. Marcos Departamento de Química Universidad Autónoma de Madrid Cantoblanco, 28049 Madrid (Spain) [d] Prof. T. Torres IMDEA-Nanociencia C/Faraday 9, Cantoblanco, 28049 Madrid (Spain) Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/chem.201301630. Abstract: In a novel electron-donor– acceptor conjugate, phthalocyanine (Pc) and perylenediimide (PDI) are connected through a trans-platinum(II) diacetylide linker to yield Pc-Pt-PDI 1. In the ground state, the presence of Pt II disrupts the electronic communication between the two electroactive compo- nents, as revealed by UV/Vis spectro- scopy and electrochemical studies. The photophysical behavior of 1 is com- pared with that of the corresponding Pc-PDI electron-donor–acceptor conju- gate 2 in terms of charge separation and charge recombination. The inser- tion of Pt II between Pc and PDI im- pacts the results in a longer-lived PcC + /PDIC  radical ion-pair state. In addi- tion, the intermediately formed Pc trip- let excited state is formed with higher quantum yields in 1 than in 2. Keywords: perylenediimides · elec- trochemistry · photophysics · phtha- locyanines · platinum acetylide Chem. Eur. J. 2013, 00,0–0  2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim These are not the final page numbers! ÞÞ &1& FULL PAPER