Platinum-Catalyzed Selective Hydration of Hindered Nitriles and Nitriles with Acid- or Base-Sensitive Groups
摘要:
Hindered tertiary nitriles can be hydrolyzed under neutral and mild conditions to the corresponding amides using platinum(II) catalysts with dimethylphosphine oxide or other secondary phosphine oxides (SPOs, phosphinous acids) as ligands. We have found that this procedure also works well for nitriles with acid- or base-sensitive groups, which is unprecedented in terms of yield and selectivity. The catalyst loading can be as low as 0.5 mol %. Amides are isolated as the only product in high yield, and no further hydrolysis to the corresponding acids takes place. Reactions are carried out at 80 degreesC but take place even at room temperature. When enantiopure secondary phosphine oxide ligands are used in the hydrolysis of racemic nitriles, no kinetic resolution is observed, presumably due to racemization of the ligand during the reaction.
Selecting a stationary phase for a fluid analyzer using certain criteria to determine an appropriate material for use in, for instance, a micro fluid analyzer. High absorption of an analyte or sample, low water sorbency and high porosity or permeability of the material may be sought. A selected material may incorporate a toughening agent using a neutral leaving group. A selected material may have a capping agent to promote hydrophobicity. A selected material may be a hydrophobic polymer. The selection of a stationary phase may involve molecular modeling.