New lyotropic phases (thermally-reversible organogels) of simple tertiary amines and related tertiary and quaternary ammonium halide salts
Small concentrations of some structurally simple tertiary amines and related tertiary and quaternary ammonium halide salts form viscoelastic, thermally reversible gels with a wide variety of organic liquids.
Hexameric resorcinarene capsule is a bronsted acid: Investigation and application to synthesis and catalysis
Molecular capsules have attracted interest as simple enzyme mimetics and several examples of catalytic transformations in water-soluble metal-ligand based systems have been reported. This is not the case for hydrogen-bond based molecular capsules, which in contrast can be employed in organic solvents. We describe herein our investigations of such a system: The resorcin[4]arene hexamer is one of the largest hydrogen bond-based self-assembled capsules and has been studied intensively due to its ready availability. We present evidence that the capsule acts as a reasonably strong Bronsted acid (pK a approximately 5.5-6). This finding explains the capsule's high affinity toward tertiary amines that are protonated and therefore encounter cation-π interactions inside the cavity. We were able to translate this finding into a first synthetic application: A highly substrate-selective Wittig reaction. We also report that this property renders the capsule an efficient enzyme-like catalyst for substrate selective diethyl acetal hydrolysis.
Conversion of Primary Amines to Symmetrical Secondary and Tertiary Amines using a Co-Rh Heterobimetallic Nanocatalyst
Symmetrical tertiary amines have been efficiently realized from amine and secondary amines via deaminated homocoupling with heterogeneous bimetallic Co2Rh2/C as catalyst (molar ratio Co:Rh=2:2). Unsymmetric secondary anilines were produced from the reaction of anilines with symmetric tertiary amines. The Co2Rh2/C catalyst exhibited very high catalytic activity towards a wide range of amines and could be conveniently recycled ten times without considerable leaching. (Figure presented.).
Chung, Hyunho,Han, Seulgi,Chung, Young Keun,Park, Ji Hoon
supporting information
p. 1267 - 1272
(2018/02/12)
Preparation of esters of phosphorus acids
Esters of phosphorus acids are prepared by an improved process whereby aromatic alcohols and phosphorus halides are reacted at specified temperatures in the presence of amine catalysts thereby providing high yields of substantially pure esters and allowing preparation of selected halogen-containing mono- and di-esters of phosphorus acids wherein halogen is directly bonded to phosphorus having substantially no side reactant contamination. The phosphorus esters are useful as intermediates in the preparation of plasticizers, oil additives and functional fluids.