摘要
sigma-Metalation of tetracene can change the emission color of and introduce new structural dimensionality to the organic chromophore. Two synthetic entries to sigma-metallotetracenes have been explored, leading to emissive mononuclear (Ph(3)PAu(I))-tetracene (1) and cis-[Br(Et(3)P)(2)Pt(II)]-tetracene (2) and binuclear (R3PAu(I))(2)-tetracenyldiacetylide (R = Ph (4), Me (5)) and trans-[I(Et(3)P)(2)Pt(II)](2)-tetracenyldiacetylide (6). Metalation can lower the emission energy of tetracene up to 0.53 eV. The X(Et(3)P)(2)Pt(II) group (X = Br, I) has stronger perturbations on the tetracenyl ring than the R3PAu(I) group. sigma-Metalation also leads to different crystal packing of the complexes and thus arrangements of the tetracenyl rings. Aurophilic attraction operates in 5, leading to self-assembly of the molecules into a novel honeycomb structure composed of helical Au(I) chains. In contrast to the other complexes, the crystal of 5 is not emissive, possibly due to efficient exciton delocalization.
- 出版日期2010-6-14