Preparation of New Solid Superbase and Its Catalytic Activity

Abstract

A solid superbase whose basicity (H−) was higher than 37 was prepared by the successive treatment of γ-alumina with sodium hydroxide and sodium at 280–350 °C under nitrogen. The base was highly effective in the catalytic isomerization of 5-vinylbicyclo[2.2.1]hept-2-ene to 5-ethylidenebicyclo[2.2.1]hept-2-ene.

Facile, Efficient Copolymerization of Ethylene with Bicyclic, Non‐Conjugated Dienes by Titanium Complexes Bearing Bis(β‐Enaminoketonato) Ligands

“…The same 4:1 mole ratio observed for the E/Z configurational isomers of the ENB monomer was also detected for the structures 2a and 2b. [10] This result indicates that both ENB isomers reacted with the same probability. Figure 2 shows the 13 C NMR spectrum of polyA C H T U N G T R E N N U N G (E-co-ENB) (entry 10).…”

Lanthanum Oxide Supported on Carbon Nanofibers as Solid Base Catalysts

“…Industrially, base catalysts are often used as homogeneous catalysts, for example, solutions of NaOH, KOH, or KOCH 3 , although solid base catalysts have several advantages. [3] Important examples are alkali metal oxides, alkaline earth metal oxides, rare earth oxides, [8] metal-exchanged zeolites, [9][10][11] supported alkali metal ions, [12,13] hydrotalcites, [14][15][16] and KF supported on alumina. [4][5][6][7] Various different types of solid base catalysts have been investigated.…”

“…[4][5][6][7] Various different types of solid base catalysts have been investigated. [3] Important examples are alkali metal oxides, alkaline earth metal oxides, rare earth oxides, [8] metal-exchanged zeolites, [9][10][11] supported alkali metal ions, [12,13] hydrotalcites, [14][15][16] and KF supported on alumina. [17] Bulk lanthanum oxide is known to act as a base catalyst for 1-butene isomerization, 1,3-butadiene hydrogenation, and methane D 2 exchange, [18][19][20] whereas it is inactive for other reactions, such as the Michael addition.…”

Isomerization of 5-Vinyl-2-norbornene Using Sodium-coated Catalysts

“…6 To correlate the activity of the prepared sodium coated catalysts with their base strengths, the distribution of base strength was measured using Hammett-Deyrup H-function. It is assumed that if a solid base can change the color of an indicator, the base strength of the solid is greater than or at least equal to the pK BH of the indicator.…”

“…4,5 There are also known solid super base catalysts such as alkali metal supported on alumina, silica gel, or active carbon with a large surface area, but these catalysts require extreme care in handling due to their instability toward air and water. [6][7][8][9] Nonetheless, as long as the reaction can be conducted in an airless condition, heterogeneous catalyst system is more attractive than the homogeneous catalyst system in terms of industrial point of view because there is no need of solvent and catalyst recovery.…”