By reactions of metallic magnesium

A variety of methods for preparing organomagnesium compounds utilize elemental magnesium, and for many of them the purity and form of the metal is important or even critical. 

Allylmagnesium bromide Allylmagnesium chloride Benzylmagnesium chloride 

Bis(pentamethyIcyclopentadienyl)magnesium (decamethylmagnesocene) n-Butyl-s-butylmagnesium n-Butylmagnesium chloride 

Ethynylmagnesium bromide 4-Fluoro-3-methylphcnylmagnesium bromide 4-Fluorophcnylmagncsium bromide 

Magnesium anthracenide (9,10-dihydro-9.10-anthracenediyl)tris(tetrahydrofuran)magncsium) Mesitylmagnesium bromide (2,4.6-trimethyI-phcnylmagnesium bromide) 4-Methoxyphenylmagnesium bromide Methylmagnesium bromide 

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The pyrometaHurgical processes, ie, furnace-kettle refining, are based on (/) the higher oxidation potentials of the impurities such as antimony, arsenic, and tin, ia comparison to that of lead and (2) the formation of iasoluble iatermetaUic compounds by reaction of metallic reagents such as 2iac with the impurities, gold, silver and copper, and calcium and magnesium with bismuth (Fig. 12). 

The Grignard reagent, we recall, has the formula RMgX, and is prepared by the reaction of metallic magnesium with the appropriate organic halide (Sec. 3.16). This halide can be alkyl (P, 2°, 3°), aJlylic, aralkyl (c.g., benzyl), or aryl (phenyl... 

The arylsulfonium metal halide complex salts are not readily available. Triphenylsulfoniurn hexafluorophosphate can be prepared from diphenyliodonium hexafluorophosphate by heating with phenyl sulfide, as described by Knapczyk and McEwen ( ), or by reaction of phenyl magnesium bromide with diphenyl sulfoxide followed by reaction with hexafluorophosphoric acid according to the procedure of Wildi, Taylor and Potratz (60). 

Scandium group elements as well as the lanthanides form allyl complexes in which the central atom has H- 3 oxidation state, while the actinides give compounds possessing + 4 oxidation states (Table 7.14). These complexes are formed by reactions of metal halides with allyl compounds of magnesium, lithium, tin, etc. " " ... 

The majority of the iodides and bromides in this chapter is synthesized by reaction of metallic tin with the corresponding halides of the carboxylic acid esters or amides at 120 to I70 in presence of catalytical amounts of magnesium alkyl iodides and polar solvents. The chlorides and some bromides issue from interconversion reactions of the heavier halides via oxides or hydroxides which are usually not isolated. Yields for the heavy halides prepared by the direct synthesis with metallic tin vary from below 20 to 70% and are greatly enhanced by the above mentioned catalysts. Structure as octahedral coordina tion compounds under inclusion of the carbonyl group but not the amide group is stated and spectroscopic evidence for this structure is forewarded. The compounds compiled in Table 1 7 are prepared by the following methods. 

Grignard reagents, organomagnesium halides, are prepared by the reaction of metallic magnesium with a wide range of organic halides (reaction 9.3). Dry ether type solvents are essential. 

Isopropyl alcohol can be oxidized by reaction of an a,P-unsaturated aldehyde or ketone at high temperature over metal oxide catalysts (28). In one Shell process for the manufacture of aHyl alcohol, a vapor mixture of isopropyl alcohol and acrolein, which contains two to three moles of alcohol per mole of aldehyde, is passed over a bed of uncalcined magnesium oxide [1309-48-4] and zinc oxide [1314-13-2] at 400°C. The process yields about 77% aHyl alcohol based on acrolein. 

Alternatively, the TiCl may be reduced using hydrogen, sodium, or magnesium. It follows that TiCl2 is the first stage in the KroU process for the production of titanium metal from titanium tetrachloride. A process for recovery of scrap titanium involving the reaction of scrap metal with titanium tetrachloride at >800° C to form titanium dichloride, collected in a molten salt system, and followed by reaction of the dichloride with magnesium to produce pure titanium metal, has been patented (122,123). 

A related class of compounds are the alkyl-magnesium alkoxides these can be prepared by reaction of MgR2 with an alcohol or ketone or by reaction of Mg metal with the appropriate alcohol and alkyl chloride in methylcyclohexane solvent, e.g. ... 

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