Browsing by Subject "Carbenoid"

Cationic gold(I) complexes have recently contributed to significant developments in homogenous catalysis. Such complexes have been praised as highly effective catalysts for the functionalization of C-C multiple bonds, leading to research on cationic gold-catalysts developing at an aggressive pace. Despite the progress being made surrounding gold(I)-catalysis, there are still many gaps in our fundamental understanding of the key intermediate complexes and their reactivity in these transformations, exemplified by the often evoked gold alpha-oxo carbene species. While there are existing computational studies suggesting the instability of gold alpha-oxo carbene species, there lacks any experimental evidence to support the stability and reactivity of alternate key intermediate species, such as gold alpha-oxo carbenoid species and gold N-alkenoxypyridinium/sulfonium complexes. Herein, we address the issues surrounding the formation of gold alpha-oxo carbene species in reported literature. We report the synthesis and reactivity of gold pyridinium alpha-oxo carbenoid complexes, gold sulfonium alpha-oxo carbenoid complexes, and gold alpha,alpha-dioxo carbenoid complexes. We then report the direct observation of a gold N-alkenoxysulfonium complex in a gold-catalyzed alkynyl sulfoxide rearrangement reaction and the synthesis of a series of gold-oxide compounds. Together, this research addresses the gaps in knowledge surrounding key intermediate species in gold(I)-catalyzed transformations.