(Isocyanoaryl)acetylides as bridging ligands in rigid-rod polymers: Mononuclear and oligonuclear gold(I) complexes

Article abstract of DOI:10.1021/om00036a017

The new ethynylaryl isocyanide ligands 4-C≡NC₆H₄C≡CH (1a) and 4-C≡N-3-MeC₆H₃C≡CH (1b) have been prepared. They react with [AuCl(SMe₂)] and with [(AuC≡C-t-Bu)_x] to give the isocyanide complexes [ClAu(4-C≡NArC≡CH)] (2a, Ar = C₆H₄; 2b, Ar = 3-MeC₆H₃) and [t-BuC≡CAu(4-C≡NArC≡CH)] (6a, Ar = C₆H₄; 6b, Ar = 3-MeC₆H₃), respectively. The complex [t-BuC≡CAuC≡NXy] (Xy = 2,6-Me₂C₆H₃) reacts with the acidic alkyne 4-NO₂C₆H₄C≡CH to give t-BuC≡CH and [4-NO₂C₆H₄C≡CAuC≡NXy]. A similar reaction uses the more acidic alkyne in 6 to displace t-BuC≡CH from 6 and so give the linear rigid-rod oligomers [t-BuC≡C(AuC≡NArC≡C-J_xH] (7a, Ar = C₆H₄; 7b, Ar = 3-MeC₆H₃). The complexes 2a and 6b have been characterized by X-ray structure determinations (2a, monoclinic, P2₁/m, a = 10.042(2) ?, b = 7.067(2) ?, c = 6.596(1) ?, β = 98.79(2)°, V = 462.6(1) ?³, Z = 2, R = 0.0427, R_w = 0.0402; 6b, monoclinic, P2₁/n, a = 14.225(4), b = 16.196(4), c = 6.747(2) ?, β = 93.86(3)°, V = 1551.0(8) ?³, Z = 4, R = 0.0332, R_w = 0.0396), while the oligomers 7 have been characterized by elemental analysis and by comparison of the IR and XPS parameters with those of the model compounds 6.