Carbonyls inorganic syntheses

There have been several reports of the preparation of MoCIsfTHFla, all based on reductive procedures starting from MoCls. " These procedures cannot be extended to the corresponding bromide and iodide compounds for lack of suitable higher-valent precursors. The alternative approach developed for these two compounds and reported here is based on the oxidative decarbonylation of lower-valent carbonyl precursors. For the preparation of the bromide compound, the commercially available Mo(CO)6 is a suitable starting compound. For the preparation of the iodide compound, on the other hand, Mo(CO)s is not sufficiently reactive to be oxidized by I2 and the more reactive (i/ -C6H5CH3)Mo(CO)3 is used instead. Because the latter compound is not commercially available and its preparation has not been previously described in Inorganic Synthesis, we also report here a detailed description of its synthesis. 

As we learned in Chapters 3 and 4, many inorganic compounds, not just ammonia, are derived from synthesis gas, made from methane by steam-reforming. In the top 50 this would include carbon dioxide, ammonia, nitric acid, ammonium nitrate, and urea. No further mention need be made of these important processes. We discussed MTBE in Chapter 7, Section 4, and Chapter 10, Section 9, since it is an important gasoline additive and C4 derivative. In Chapter 10, Section 6, we presented -butyraldehyde, made by the 0x0 process with propylene and synthesis gas, which is made from methane. In Chapter 11, Section 8, we discussed dimethyl terephthalate. Review these pertinent sections. That leaves only two chemicals, methanol and formaldehyde, as derivatives of methane that have not been discussed. We will take up the carbonylation of methanol to acetic acid, now the most important process for making this acid. Vinyl acetate is made from acetic... 

Reductive carbonylation in alkaline methanol solution of Na2[PtCl6] 6H20 gives the series of dianions [Pt3(CO)6]2 (n = 3-10) the value of n depends on the alkaline reagent and the experimental conditions.1 The lowest term of this series of inorganic oligomers, which has been isolated in the solid state, is the [Pt6(CO)12]2- dianion. Its reported synthesis is based on the reduction with lithium metal in tetrahydrofuran (THF) of Pt(CO)2Cl2, or of preformed [Pt3(CO)6]2 (n > 3).1,2... 

Caution. Toxic, colorless, odorless carbon monoxide is evolved in this reaction and must be properly vented. All metal carbonyls should also be considered to be toxic compounds. The drying of tetrahydrofuran (THF) may be accompanied by serious explosions under certain conditions. [See Inorganic Syntheses, 12, 111, 317 (1970) also Synthesis 1, this volume.]... 

The oxidation of primary and secondary alcohols into the corresponding carbonyl compounds plays a central role in organic synthesis [1, 139, 140]. Traditional methods for performing such transformations generally involve the use of stoichiometric quantities of inorganic oxidants, notably chromium(VI) reagents [141]. However, from both an economic and environmental viewpoint, atom efficient, catalytic methods that employ clean oxidants such as 02 and H202 are more desirable. 

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