A non-metallic catalyst refers to a compound that is catalytically active but does not contain metal atoms or metal ions.
- Arsenic Catalysts: The arsenic compound can be used as a homogeneous catalyst for the hydroboration of acetaldehyde. The benzo-fused diazabenzyloxy arsine as a procatalyst can be used under mild conditions to rapidly quantitatively convert to a reduced product, most of which can be completed in 30 minutes. This catalyst utilizes Lewis acid reduction reactivity of arsenic to provide a new direction for catalyst design.
- Phosphorus Catalysts: Axially chiral BINOL-derived phosphoric acids have been widely used as a catalyst in various organic reactions. For example, in Mannich type reaction, a phosphoric acid catalyst can be fully effective. Different substituents of the phosphoric acid catalyst have a large effect on the reactivity and enantioselectivity of the products. The racemic product yield of the parent compound is lower, while the reactivity and enantioselectivity of the 3,3'-phenyl substituent are significantly increased. The 4-nitrophenyl substituent has good yields and high enantiomeric excess (e.e.) values when the reaction time is shortened.
- Nitrogen-containing Catalysts: Nitrogen-containing catalysts are mainly used as cathodic redox catalysts for direct methanol fuel cells or oxygen reduction reactions in electrochemistry. In organic synthesis industry,they can be used for asymmetric synthesis.
- Boron Catalysts: The aryl boronic acid having an electron withdrawing group functions as a highly efficient catalyst in the amidation between the carboxylic acids. The aryl boronic acid having an electron-withdrawing substituent on the aryl group is a water-, acid- and base-resistant Lewis acid which can produce an acyloxy group. It is also thermally stable and easy to handle in air. At the same time, strong Lewis acidity may increase the rate of formation of the acyloxy species and its reactivity with amines.
- Silicon Catalysts: Tris(trimethylsilyl)silane is an effective alternative to toxic tributyltin hydride in the reduction of organic halide radical chains. It is used in a catalytic amount and is regenerated in situ by using sodium borohydride. Tris(trimethylsilyl)silane can be used as a catalyst in a free radical mediated reduction reaction.
- Selenium Catalysts: Selenium compounds can be applied to a series of catalytic reactions, including olefin epoxidation, olefin dihydroxylation, olefin hydroxyhalogenation, activated carbon-hydrogen bond oxidation, Baeyer-Villiger oxidation, amine oxidation and so on.