Chemical mechanical planarization composition

H2, and amines (piperidine, aniline, or NEtg). In the presence of an amine and syngas (CO/H2 = 1 2), the trigonal bipyramidal complex 3 was formed, irrespective of whether 1,5-cyclooctadiene (COD) complex 1 or dicarbonyl complex 2 was used as a precursor (Scheme 5.91). Complex 3 is a typical hydroformylation precatalyst with detailed description of composition and geometric structure in the literature [27]. The square-planar complex 2 - its structure could be proven by X-ray structural analysis - reacts with H2 to produce the corresponding dihydride 6. Upon oxidative addition of H2 and in the absence of CO, the binu-clear rhodium complex 5 is formed. Under CO, the latter is in equilibrium with the neutral complex 3. Chemical calculations provided evidence that an amine assists in the deprotonation of 6 to produce 3 via an outer-sphere mechanism. 

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