Steering alkyne homocoupling with on-surface synthesized metal–organic complexes
JUNE 23, 2020
Mohammed S. G. Mohammed, Luciano Colazzo, Aurelio Gallardo, Jose´ A. Pomposo, Pavel Jelınek and Dimas G. de Oteyza
Chemical Communications 56, 8659-8662 (2020)
In this work we demonstrated the changes in the reactivity of 1-ethynyl-pyrene on Au(111) brought by the presence of Au–thiolate-based metal–organic complexes. The Au3BMB3 metal-organic complexes are first formed, as described in a previous work, by deposition of 1,4-Bis(4-mercaptophenyl)benzene (BMB) on Au(111). Whereas only one type of covalent homo-coupling motif was found for the 1-ethynyl-pyrene on Au(111) in the absence of the metal–organic complexes, in the proximity of the Au3BMB3 complex, a head-to-tail alkyne coupling is obtained. This work takes a step further in the development of on-surface synthesis. An initial surface-supported synthesis of metal–organic complexes is used to steer on-surface alkyne coupling reactions. In doing that, the threshold temperature for the reaction activation is lowered and the dominant product outcome is modified.
We report a multi-step on-surface synthesis strategy. The first step consists in the surface-supported synthesis of metal–organic complexes, which are subsequently used to steer on-surface alkyne coupling reactions. In addition, we analyze and compare the electronic properties of the different coupling motifs obtained.