Formation and ligand-based reductive chemistry of bridged bis-alkylidene scandium(iii) complexes. Issue 10 (15th August 2017)

• Record Type: Journal Article
• Authors: Ma, Wangyang; Yu, Chao; Chi, Yue; Chen, Tianyang; Wang, Lianjun; Yin, Jianhao; Wei, Baosheng; Xu, Ling; Zhang, Wen-Xiong; Xi, Zhenfeng
• Is Part Of: Chemical science. Volume 8:Issue 10(2017)
• Page Start: 6852
• Page End: 6856
• Publication Date: 2017-08-15
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c7sc02018j
• Languages: English
• ISSNs: 2041-6520

Abstract

Abstract : Bridged bis-alkylidene Sc(iii ) complexes featuring a 2-butene-1, 1, 4, 4-tetraanion are synthesized and show unexpected ligand-based two-electron or four-electron reduction reactivity towards different oxidants. Abstract : The chemistry of rare-earth carbene and alkylidene complexes including their synthesis, structure and reaction is a challenging issue because of their high reactivity (or instability) and the lack of synthetic methods. In this work, we report the first synthesis of the bridged bis-alkylidene complexes which feature a 2-butene-1, 1, 4, 4-tetraanion and four Sc–C(sp 3 ) bonds by the reaction of 1, 4-dilithio-1, 3-butadienes with ScCl3 . This reaction proceeds via two key intermediates: an isolable scandacyclopentadiene and a proposed scandacyclopropene. The scandacyclopentadiene undergoes β, β′-C–C bond cleavage to generate the scandacyclopropene, which then dimerizes to afford the bridged bis-alkylidene complex via a cooperative double metathesis reaction. Reaction chemistry study of the bridged bis-alkylidene complex reveals their ligand-based reduction reactivity towards different oxidants such as hexachloroethane, disulfide and cyclooctatetraene.