UC Santa Barbara
Gold Catalysis Enabled Cascade Reactions from C-C Triple Bonds
- Author(s): Zheng, Zhitong
- Advisor(s): Zhang, Liming
- et al.
Homogeneous gold catalysis has been a very hot topic in recent decades. With its unparalleled π-acidity, cationic gold complex exhibits a strong affinity to alkynes and promotes nucleophilic attack across C-C triple bonds. Such nucleophilic attacks lead to various reactive intermediates that trigger a wide range of cascade reactions, building molecular complexity readily in one step. My doctoral study is focused on the development and application of gold-catalyzed cascade reaction with alkyne substrates. In this dissertation, two methodology studies and two applications of gold-catalyzed cascades will be discussed. Namely: 1) one-pot synthesis of fused pyrroles from ketones and N-alkylhydroxylations via a gold catalysis-triggered cascade; 2) synthesis of polycyclic 2H-pyran-3(6H)-ones via a vinyl cation C(sp3)-H insertion triggered by oxidative gold catalysis; 3) streamlined synthesis of highly potent mitomycin C analogs with gold/platinum-catalyzed cycloisomerization cascade; and 4) gold-catalysis-activated stereoselective glycosylation reaction to construct 1,2-cis glycosyl linkage in glycoconjugates and oligosaccharides.