Synthesis and XPS characterization of Si-supported chromium(0) Fischer aminocarbene complexes

Abstract

Ethoxy chromium (0) Fischer carbene pentacarbonyl complexes [(CO)5CrC(OEt)R]; R = 2- thienyl (1), 2-furyl (2) were covalently anchored onto aminopropyltrimethoxysilanefunctionalised silicon-wafers to form Cr-grafted Si-wafers S1 and S2 that were characterized by X-ray photoelectron spectroscopy (XPS). X-ray photoelectron spectroscopy determined that binding energy of the Cr 2p3/2 photoelectron line of the thienyl-containing complexes were smaller than that of the furyl-containing complexes. The binding energy of the Cr 2p3/2 photoelectron line of the ethoxycarbene complexes was smaller than that of aminocarbenes. The binding energy of the Cr 2p3/2 photoelectron line of the Cr-grafted Si-wafers were ca. 1 eV higher than that of the related aminocarbenes. A 25 – 33 % anchoring of the Crcomplexes 1 and 2 on the aminopropyltrimethoxysilane-functionalised silicon-wafers was achieved.