Linear 6,6'-biazulenyl framework featuring isocyanide termini: synthesis, structure, redox behavior, complexation, and self-assembly on Au(111).
The key step in accessing the title species (5), the first nonbenzenoid diisocyanobiaryl, involved an unexpected homocoupling of a 6-bromoazulene derivative. The reversible 2e(-) reduction of 5 was addressed electrochemically and computationally. The shifts in energies of the S(0)→S(1) and S(0)→S(2) transitions for a series of related 6,6'-biazulenyl derivatives correlate with the e(-)-donating/-withdrawing strength of their 2,2'-substituents but follow opposite trends. Species 5 adsorbs end-on (η(1)) to the Au(111) surface via one of its -NC groups to form a 2-nm-thick film. In addition, bimetallic coordination of 5's -NC termini can be readily achieved.
Maher
Tiffany R
TR
Department of Chemistry, University of Kansas, 1251 Wescoe Hall Drive, Lawrence, Kansas 66045, USA.
Spaeth
Andrew D
AD
Neal
Brad M
BM
Berrie
Cindy L
CL
Thompson
Ward H
WH
Day
Victor W
VW
Barybin
Mikhail V
MV