In situ Raman monitoring triazole formation from self-assembled monolayers of 1,4-diethynylbenzene on Ag and Au surfaces via "click" cyclization.
We prepared acetylenyl-terminated aromatic self-assembled monolayers (SAMs) of 1,4-diethynylbenzene on silver and gold. After the fabrication of pendent acetylenyl SAMs, the formation of triazoles was performed via Cu(I)-catalyzed Huisgen 1,3-dipolar cycloaddition "click" chemistry. A density functional theory (DFT) calculation of Raman frequencies showed good agreement with our experimental data to provide evidence of the formation of the triazole molecule. Our results indicated that "click" chemistry could be successfully applied to simple aromatic SAMs proximate (<1 nm) to roughened gold surfaces. The reaction process could be monitored in real time by measuring intensity changes of the nu(CC)(free) band in surface-enhanced Raman scattering (SERS) spectra.
Yoo
Bum Keun
BK
Department of Chemistry, Soongsil University, Seoul 156-743, South Korea.
Joo
Sang-Woo
SW
D000114:Acetylene / Q000031:analogs & derivatives* / Q000737:chemistry; D001555:Benzene Derivatives / Q000737:chemistry*; D003500:Cyclization; D006046:Gold / Q000737:chemistry*; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000379:methods; D013499:Surface Properties; D014230:Triazoles / Q000138:chemical synthesis*
C522707:1,4-diethynylbenzene; D001555:Benzene Derivatives; D014230:Triazoles; D012834:Silver; D006046:Gold; D000114:Acetylene