McMurry Coupling of Diformyldithienylacetylene: Synthesis of [24]-, [36]-, and [48]Annulenes Composed of Thiophene, Acetylene, and Ethylene Units
作者:Masahiko Iyoda、Pochi Huang、Tomohiko Nishiuchi、Masayoshi Takase、Tohru Nishinaga
DOI:10.3987/com-10-s(e)96
日期:——
The reaction of diformyldithienylacetylene 4 with a McMurry reagent prepared from TiCl(4), Zn, and pyridine in THF afforded 24 pi-dimer 1b (15%), 36 pi-trimer 2b (13%), and 48 pi-tetramer 3b (6%). From X-ray analysis, 1b adopts a twisted conformation, although the (1)H NMR spectrum of 1b shows a symmetrical structure owing to a rapid conformational change in solution. Absorption and emission spectra, redox properties, and electric conductivities of 1b-3b were measured in order to study the structure-property relationship of these macrocyclic systems.