Magnesium syntheses

Calcium has received some application in organic synthesis similar to that of magnesium alkyl and aryl compounds, CaRa, have been prepared, and it seems likely that many of the magnesium syntheses, already mentioned, could be accomplished by the use of calcium. 

Y. H. Lai, Grignard Reagents from Chemically Activated Magnesium, Synthesis 1981, 585. 

T itanium tetrachloride I magnesium Synthesis of ethers from acetals... 

Magnesium Synthesis of alcohols from glycol monosulfates... 

Lai, Y.-H. (1981) "Grignard reagents from chemically activated magnesium" Synthesis, 585-604. 

AHylestrenol (37) is prepared from (32), an intermediate in the synthesis of norethindrone. Treatment of (32) with ethanedithiol and catalytic boron trifluoride provides a thioketal. Reduction with sodium in Hquid ammonia results in the desired reductive elimination of the thioketal along with reduction of the 17-keto group. Oxidation of this alcohol with chromic acid in acetone followed by addition of aHyl magnesium bromide, completes the synthesis... 

Uses and Economic Aspects. Magnesium bromide is used in medicine as a sedative in treatment of nervous disorders, in electrolyte paste for magnesium dry cells, and as a reagent in organic synthesis reactions. The price of magnesium bromide hexahydrate in January 1995 was 5.51/kg (33). 

As an activator of the phosphokinases, magnesium is essential in energy-requiring biological processes, such as activation of amino acids, acetate, and succinate synthesis of proteins, fats, coen2ymes, and nucleic acids generation and transmission of nerve impulses and muscle contraction (67). 

Typical values for mf n are 0.5 to 2.5. Gommercially used bases include sodium hydroxide, potassium hydroxide, calcium hydroxide (lime), magnesium hydroxide, sodium carbonate, sodium alurninate, calcium carbonate, or various mixtures. For certain appHcations, PAG can be made from waste grades of aluminum chloride [7446-70-0] such as spent catalyst solutions from Friedel-Grafts synthesis (see Friedel-Grafts reaction). 

Dry methyl chloride is unteactive with all common metals except the alkaU and alkaline-earth metals, magnesium, 2iac, and alumiaum. In dry ether solution, methyl chloride reacts with sodium to yield ethane by the Wurt2 synthesis ... 

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