Isoreticular Tp-W-Cu-S cluster-based one-dimensional coordination polymers with an uncommon [TpWSCu] + [Cu] combination and their third-order nonlinear optical properties

• Published in: CrystEngComm 2019-05, Vol.21 (21), p.3343-3348
• Main Authors: Liu, Quan, Xu, Hong-Juan, Yu, Li-Ce, Lu, Ming-Jie, Shang, Yan-Fang, Song, Ying-Lin, Zhang, Wen-Hua, Lang, Jian-Ping
• Format: Article
• Language: English
• ISSN: 1466-8033; 1466-8033
• DOI: 10.1039/c9ce00439d

We herein report three isoreticular Tp*-W-Cu-S cluster-based one-dimensional coordination polymers, namely, [Tp*WS 3 Cu 2 (CN) 2 Cu](pz) 0.5 ( 2 ), [Tp*WS 3 Cu 2 (CN) 2 Cu](bipy) 0.5 ·0.5DMF ( 3 ), and [Tp*WS 3 Cu 2 (CN) 2 Cu](bpb) 0.5 ·DMF ( 4 ), from the reaction of [Et 4 N][Tp*WS 3 ] ( 1 ) with CuCN in the presence of bridging ligands pyrazine (pz), 4,4′-bipyridine (bipy), and 1,4-bis(4-pyridyl)benzene (bpb) under solvothermal conditions. In 2-4 , a pair of butterfly-shaped [Tp*WS 3 Cu 2 ] + clusters are connected by two [Cu(CN) 2 ] − units to give a macrocyclic unit, which is further strung by pz/bipy/bpb to give linear chains. Besides their rare isoreticular nature, 2-4 are also unique in that they contain a [Tp*WS 3 Cu 2 ] + [Cu] combination instead of the widely acknowledged nest-shaped [Tp*WS 3 Cu 3 ] 2+ or cuboidal [Tp*WS 3 Cu 3 X] + (X = Cl, Br, I) cluster skeleton. Compounds 2-4 are also characterized by FT-IR, elemental analysis, UV-vis and ESI-MS. The ESI-MS results also indicate that the pz/bipy/bpb coordination is labile in solution under harsh ionization conditions, yielding CN-ligated anionic species which are assumed as the key contributors to the enhanced NLO performance of 2-4 compared to that of the starting material 1 . Three isoreticular W/Cu/S 1D coordination polymers show good third-order NLO performance.