Reductive amination infrared spectroscopy

Imanaka—heterogenization of Rh complexes. In 1991, Imanaka and coworkers124 reported the heterogenization of Rh complexes by binding them to aminated polymers. As discussed previously, these findings led to fruitful research by Ford, Pardey, and others. The isolated polymer-bound Rh carbonyl anion complex was found to be reusable for reactions such as water-gas shift and reduction of nitro compounds. The polymer-bound Rh complexes were characterized by infrared spectroscopy. Water-gas shift activity (80 mol H2 per mol Rh6(CO)i6 in 24 hours) was recorded using the Rh complexes at 100 °C with 0.92 atm of CO, 2.16 ml H20, 0.05 mmol Rh6(CO)16, aminated polystyrene, 5.0 mmol of N, 5.56 ml ethoxyethanol and reduction of nitro-compounds (e.g., aliphatic nitro compounds to nitriles, oximes to nitriles, hydroxylamines to nitriles, and N-oxides to amines) occurred at 40 °C. 

The formation of the latter complexes can be followed by infrared spectroscopy, as it involves a proton transfer from the acid of poly (acrylic acid) to the tertiary amine of the mesogens. Complexation results in a significant reduction, or almost complete elimination, for the equimolar complexes, of the acid carbonyl band near 1700 cm and the appearance of a new band near 1550cm attributed to the asymmetric carboxylate stretch. The residual carbonyl absorption that remains in the equimolar mixtures indicates the presence of a small... 

Heischer et al. [172] measured the interfacial tension reductirai credited to the complexation between carboxy-terminated PBD and amine-terminated PDMS, which were added to an immiscible blend of PBD and PDMS. The changes in interfacial tensimi resembled the behavior observed for block copolymer addition to homopolymer blends there is initially a linear decrease in interfacial tension with the concentration of functional homopolymer up to a critical concentration, at which the interfacial tension becomes invariant to further increases in the concentration of functional material. However, the formation of interpolymer complexes depends on the equilibrium between associated and dissociated functional groups and, thus, the ultimate plateau value for interfacial tension reduction is dependent on the functional group stoichiometry. A reaction model for end-complexation was developed in order to reproduce the interfacial tension reduction data with Fourier transform infrared spectroscopy applied to determine the appropriate rate constants. The model provided a reasonable qualitative description of the interfacial tension results, but was not able to quantitatively predict the critical compositions observed experimentally. 

The kinetics of the oxidations of trans-[Tc(dppe)X2] (X = Cl , Br ) by Co(III) amine complexes have been investigated in pure and mixed DMF and CH3CN solvent systems, with an observed increase in the rate constant with DMF concentrations. The rate constants for the reductions of three metal carbonyl dimers [M2,M = Mn(CO)5, CpMo(CO)3, and Co(CO)4] by [Re(CO)5r in THF (measured using infrared stopped-flow spectroscopy) do not parallel the reduction... 

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