Inter- and Intramolecular Cooperativity Effects in Alkanolamine-Based Acid-Base Heterogeneous Organocatalysts.

ABSTRACT: Intramolecular cooperativity in heterogeneous organocatalysts is investigated using alkanolamine-functionalized silica acid-base catalysts for the aldol condensation reaction of 4-nitrobenzaldehyde and acetone. Two series of catalysts, one with and one without silanol-capping, are synthesized with varied alkyl linker lengths (two to five) connecting secondary amine and terminal hydroxyl functionalities. The reactivity of these catalysts is assessed to determine the relative potential for intermolecular (silane amine-surface silanol) vs intramolecular (amine-hydroxyl within a single silane) cooperativity, the impact of inhibitory surface-silane interactions, and the role of alkyl linker length and flexibility. For the array of catalysts tested, those with longer linker lengths generally giv

SUBMITTER: Xie J 

PROVIDER: S-EPMC6648141 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature