Metal complexes mass spectra

The theoretical molar masses and the corresponding volume fractions of PS, the metal complex, and PEG content of the block copolymers are summarized in Table 14. The metal complex has been treated as the third block. All block copolymers have been purified by preparative SEC and column chromatography, with isolated yields between 10% and 80%. The expected ratios (within 10% error) for all components in the library were obtained from the integration of NMR spectrum. 

Calculations of the vibration frequencies expected for a chelate ring structure of copper cupfer-ronate, calculated on the basis of an assumed geometry and set of force constants, have been found107 to be in much better agreement with experimentally observed values than those calculated on the basis of a single ring structure. They also confirm that the observed changes at 935, 680, 580, 523 and 439 cm-1 in the spectrum of the metal complex are due to the mass of the metal. 

The mass spectra of some cyclopentadienylrhodium olefin complexes have been investigated 80>. The molecular ion in the mass spectrum of the ethylene complex CsHsRh H undergoes fragmentation to the bare metal ion by the following sequence ... 

The mass spectrum of (7r-C3H5PdCl)2 shows loss of both chlorine and allyl radicals from the molecular ion, but no ion C3H5PdCl+ corresponding to half the dimerized molecule was observed, and metal-metal interaction is proposed to account for the abundance of fragments containing the Pd2Cl unit. The base peak of the spectrum corresponds to C3H5Pd+, which can be formed from many of the other ions (132). The mass spectrum of the methoxyallyl complex (CXXIII)... 

The infrared spectrum (v(CO) 2046 and 1969 cm 1) was again consistent with the presence of the desired polymer-bound complex, [Ir(CO)2I2]. ICP mass spectroscopic analysis of the metal loaded resins showed the metal contents to be 0.56-0.66 % (Rh) and 0.79-0.86 % (Ir) by weight. These values are in line with the observation that virtually all the metal complex is taken up from solution under the conditions of these loading experiments, and that 15-20% of the pyridinium sites are loaded with metal in the products. 

---