Additions to CO and

In the dehydrogenation of isobutyric acid, the by-products in addition to CO and C02 are propylene and acetone. Two reaction mechanisms were proposed (340, 341) and the latter is shown in Scheme 9 (340). The formation of methacrylic acid and acetone involves a common intermediate The El elimination of a proton from I yields the methacrylic acid while a nucleophilic SN1 attack of oxide ion produces C02 and acetone (344). On the other hand. 

A second method is to initially grow an ice of several monolayers and expose this ice to the atomic beam while recording reflection adsorption infrared spectra (RAIRS). In this way, the reactants and products are probed in-situ at the time and temperature that one is interested in, which is the main advantage of this technique. Quantifying the formed product is relatively simple, provided that the RAIRS is calibrated with an independent method. The main disadvantages are that not all species can be detected in this way and that the sensitivity is less than with the previous technique. Most systems have an additional quadrupole mass spectrometer (QMS) installed. So far this technique has been applied to umavel the formation of the main components of interstellar ices, i.e., water, methanol, carbon dioxide, formaldehyde, and formic acid, mainly through H-atom additions to CO- and/or... 

Compounds of this type have been synthesized in addition to Co and Fe with Mn and Cr as the central metal atoms (Fig. 11) using the methods shown in Fig. 12 [36]. 

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