2,4,6-Trichloro-1,3,5-triazine (TCT) efficiently catalyzed the condensation reactions between 1,2-diamines and various enolizable ketones to afford 1,5-benzodiazepines in good to excellent yields. Simple and mild reaction conditions, the use of a cheap catalyst and easy workup and isolation are notable features of this method.

In this paper we report the binding properties, by combined 1H NMR, optical absorption, and fluorescence studies, of a molecular tweezer composed two Zn(salen)-type Schiff-base units connected flexible spacer, towards series ditopic diamines having strong Lewis basicity, with different chain length rigidity. Except for 1,2-diaminoethane, in all other cases formation stable 1:1 acid-base adducts...

The synthesis of new optically pure ferrocenyl diphosphines have been realized from (R)-(+)-N,Ndimethylaminoethylferrocene. Particularly, dissymmetric ferrocenyl diphosphines have been synthesized. The diphosphines have been used as ligands in asymmetric transfer hydrogenation of acetophenone in the presence of Ru catalysts. © 2006 Elsevier Science. All rights reserved ——— * Corresponding autho...

Five new aromatic poly(amide-imide)s (5a-e) were synthesized by direct polycondensationreaction of N-(4-carboxy phenyl) trimellitimide (3) with five aromatic diamines (4a-e) by usingtriphenyl phosphite in N-methyl-2-pyrrolidone (NMP) and pyridine at solution containingdissolved CaCl2. All of the polymers were obtained in quantitative yields with inherentviscosities between 0.29-0.40 dL/g. The r...

Chiral C₂-symmetric diamines have emerged as versatile auxiliaries or ligands in numerous asymmetric transformations. Chiral 2,2'-bispyrrolidine-based salan ligands were prepared and applied to the asymmetric aryl transfer to aldehydes with arylboronic acids as the source of transferable aryl groups. The corresponding diarylmethanols were obtained in high yields with moderate to good enantiosel...

Amination of enecarbamates with dibenzylazodicarboxylate and oxygenated nucleophiles in the presence of a catalytic amount of chiral phosphoric acid afforded optically active stable precursors of α-hydrazinoimines, which were reduced or oxidized, respectively, to vicinal diamines or α-amino acid precursors with excellent yield and enantioselectivity.

Organocatalysts containing primary-secondary diamines based on bispidine have been developed to catalyze the asymmetric Michael addition of ketones to alkylidene malonates and nitroalkenes. The corresponding products were obtained in high yields (up to 99%) with high diastereoselectivities (up to 99:1) and high enantioselectivities (up to 97% ee) under mild conditions using either environmental...