Intrinsic Role of Molecular Architectonics in Enhancing the Catalytic Activity of Lead in Glucose Hydrolysis.

Lewis acidity plays a key role in the catalytic activity of lead ion (PbII) in the hydrolysis of glucose in solution under harsh synthetic conditions. We report a number of structurally similar d-gluconamide amphiphiles as functional organic ligands with active an -NH center capable of coordinating PbII (viz., PbII-N-C) in basic condition to enhance the catalytic efficiency through the scheme of molecular architectonics. Amphiphiles with different hydrophobic unit form assembly-architectures with a varying second coordination sphere around the active metal ion center. As a result, the active PbII center in each architecture exhibits substantially different efficiency toward catalyzing the glucose hydrolysis under ambient temperature. The catalytic performance of the dynamic and reversible gluconamide-PbII assembly-architectures are highly dependent on their chemical environments in solution. Further, the active PbII center of gluconamide-PbII complex in the assembly architecture and dispersed states exhibits distinct outcomes with the former being a superior catalyst than the latter as well as PbII alone. The current study demonstrates the potential of molecular architectonics that relies on the hydrophobic units of designer functional amphiphiles to enrich surface electron density with enhanced σ-donation ability through space which substantially improves the catalytic efficiency of PbII toward glucose hydrolysis at ambient temperature.