Novel chiral N4S2- and N6S3-donor macrocyclic ligands: synthesis, protonation constants, metal-ion binding and asymmetric catalysis in the Henry reaction.

New hydrophobic chiral macrocyclic ligands L1-L3 with chiral diamino and thiophene moieties have been synthesized by the Schiff base condensation approach. Protonation constants of L1 and L2 were determined by potentiometry titration. Metal-ion binding experiments exhibited that L1 and L3 are pronounced in selective recognition, Ag+, Cu2+ and Ca2+ ions among the surveyed metal ions (Cu2+, Co2+, Ni2+, Zn2+, Cd2+, Pb2+, Ag+, Li+, Na+, K+, and Ca2+). L1 was found to spectroscopically detect the presence of Cu2+ and Ca2+ to function as a multiple readout sensor. The detection limit for Ca2+ ions was found to be 9.8 x 10(-5) M in CH2Cl2-MeOH solution. The trimeric chiral ligand L3 has been shown to be an efficient auxiliary in a Zn(II)-mediated enantioselective Henry reaction.

[1]  A. Martell,et al.  New macrocyclic dicopper(II) complex: synthesis, structure and stability , 2002 .

[2]  Suk-Kyu Chang,et al.  A new fluorogenic benzothiazolyl ionophore based upon calix[4]arene-crown-5 ether for calcium determination in aqueous media , 2002 .

[3]  B. Trost,et al.  A dinuclear Zn catalyst for the asymmetric nitroaldol (Henry) reaction. , 2002, Angewandte Chemie.

[4]  A. Martell,et al.  Novel Cu(II)Cd(II) macrocyclic complex that hydrolyzes an activated phosphate diester , 2002 .

[5]  M. Welch,et al.  Synthesis and characterization of two novel macrocyclic monoxo-tetraamines and the stabilities of their Cu(II) complexes , 2001 .

[6]  P. Baxter.  Synthesis and properties of a twistophane ion sensor: a new conjugated macrocyclic ligand for the spectroscopic detection of metal ions. , 2001, The Journal of organic chemistry.

[7]  M. Welch,et al.  Synthesis, characterization, and Cu(II) solution chemistry of dioxotetraazamacrocycles , 1999 .

[8]  D. Matt,et al.  Directed Positioning of Organometallic Fragments Inside a Calix[4]arene Cavity. , 1998, Angewandte Chemie.

[9]  M. Shibasaki,et al.  Asymmetric Catalysis with Heterobimetallic Compounds , 1997 .

[10]  R. Pearson.  Hard and soft acids and bases ― the evolution of a chemical concept , 1990 .

[11]  B. Valeur,et al.  Ion-responsive fluorescent compounds. 2. Cation-steered intramolecular charge transfer in a crowned merocyanine , 1989 .

[12]  Ralph G. Pearson,et al.  HARD AND SOFT ACIDS AND BASES , 1963 .