Enantiopure Ti(IV) amino triphenolate complexes as NMR chiral solvating agents

Abstract

Enantiopure Ti(IV) complexes bearing pseudo-C(3) amino triphenolate ligands have been synthesized and characterized. The complexes bearing ortho phenyl groups act as (1)H NMR chiral solvating agent (CSA) for the stereochemical analysis of a series of sulfoxides. The coordination of a Lewis base coligand (sulfoxide) and the presence of aromatic rings are the key structural factors for the efficiency of the CSA.

Extending substrate sensing capabilities of zinc tris(2‐pyridylmethyl)amine‐based stereodynamic probe

“…[41][42][43][44][45] On a parallel track, in the recent years, we are assisting to a revival of interest in the well-known, and widely exploited in nature, imine condensation chemistry. 8,[52][53][54][55][56][57][58][59][60][61][62] In this study, we extend the sensing capabilities of our zinc TPMA-based stereodynamic probe, showing its efficiency towards chiral amines, acids, and β-amino acids. 46,47 However, the main reason of interest lies in the reversibility of the C═N bond formation, which is extremely useful in dynamic covalent chemistry (DCC) and in the synthesis of functional architectures, and it is particularly effective in the presence of transition metal complexes.…”

“…[48][49][50][51] In the recent years, we have reported several examples on the catalytic and recognition capabilities of tripodal ligands, especially focusing on the TPMA molecular sensing toward α-amino acids ( Figure 1). 8,[52][53][54][55][56][57][58][59][60][61][62] In this study, we extend the sensing capabilities of our zinc TPMA-based stereodynamic probe, showing its efficiency towards chiral amines, acids, and β-amino acids.…”

Determination of Amino Acid Enantiopurity and Absolute Configuration: Synergism between Configurationally Labile Metal‐Based Receptors and Dynamic Covalent Interactions

“…[8] The latter have been extensively examined in tetradentate metal complexes that are characterized by a propeller-like arrangement of the ligand around the metal (Figure 1). [9][10][11][12][13][14][15] Such peculiar geometry gives raise to the formation of two enantiomeric complexes in solution that are characterized by a clockwise (P) or counter-clockwise (M) arrangement of the ligand. The handedness of the molecular system can be controlled by the presence of a stereogenic center in the backbone ligand, or by a chiral guest carrying a stereo-genic element.…”

Second‐Generation Tris(2‐pyridylmethyl)amine–Zinc Complexes as Probes for Enantiomeric Excess Determination of Amino Acids

“…[9][10][11][12][13][14] In general, supramolecular sensors are characterized by the presence of at least one labile stereogenic element that, upon interaction with a chiral analyte, forms one preferential diastereoisomer. [21][22][23][24][25] This is due to 1) the stability of these systems, which are usually held together by polydentate ligands, 2) the possibility of using the metal centre as a coordination point for the analyte and 3) by the ability of these systems to adopt a stereodynamic arrangement of the ligand around the metal. [21][22][23][24][25] This is due to 1) the stability of these systems, which are usually held together by polydentate ligands, 2) the possibility of using the metal centre as a coordination point for the analyte and 3) by the ability of these systems to adopt a stereodynamic arrangement of the ligand around the metal.…”