Magnesium Grignard solutions

A solution of 85.8 g (0.2 moles) of 3/ -acetoxy-27-norchoIest-5-en-25-one in 500 ml of anhydrous thiophen-free benzene is added to a Grignard solution prepared from 24.3 g (1 g-atom) of magnesium and 149 g (1.05 moles) of freshly distilled methyl iodide in 575 ml of anhydrous ether. The mixture is refluxed for 3 hr and allowed to stand overnight. After cooling to 5° the complex is decomposed by the slow addition of 200 ml of ice water and 400 ml of 50% acetic acid solution, and steam distilled until no more oil passes over. The residual product is filtered, washed with water and dried at 80°. Crystallization from methanol gives 70 g (87%) of cholest-5-ene-3)5,25-diol mp 179.5-181°. The analytical sample melts at 181.5-182.5° [a]o —39° (CHCI3). 

A Grignard solution is prepared from 1.35 g (56 mg-atoms) magnesium, 3.7 ml (8.4 g, 59 mmoles) methyl iodide and 47 ml dry ether. After addition of 80 ml of dry tetrahydrofuran the solvent is removed by distillation until the boiling point reaches 62°. Additions of 0.27 g (2.7 mmoles) of cuprous... 

A Grignard solution is prepared by introducing methyl chloride into a boiling suspension of 36 g of magnesium in 1,000 cc of absolute ether until all the magnesium has reacted. 

A) Preparation of p-Hydroxy-p -Methoxybemhydrylidenecyclohexane To a Grignard solution prepared from 110 g of magnesium (4.5 mols) and 840 g of p-bromoanisole (4.5 mols) in one liter of anhydrous ether, there was added dropwise with vigorous agitation 307 g of p-hydroxyphenyl cyclohexyl ketone (1.5 mols) dissolved in one liter of anhydrous ether. Upon completion of the addition the reaction mixture was refluxed for 2.5 hours with agitation, and was then cooled. Thereupon 15 mols of ammonium chloride dissolved in 3 liters of water were added. The ethereal layer was separated, washed with water, dried over anhydrous sodium sulfate and distilled. Yield 370 g. BP 180° to 190°C at 0.1 mm. The substance was recrystallized from a mixture of carbon tetrachloride and petroleum ether. MP 145° to 146°C. 

To the Grignard solution, 75 g. (71.5 cc., 0.5 mole) of ethyl benzoate (Org. Syn. 10, 51) in 200 cc. of dry benzene (Note 2) is added at such a rate that the mixture refluxes gently. The flask is cooled in a pan of cold water during the addition, which requires about an hour. After the addition is complete, the mixture is refluxed for an hour on a steam bath. The reaction mixture is cooled in an ice-salt bath and then poured slowly, with constant stirring, into a mixture of 1.5 kg. of cracked ice and 50 cc. of concentrated sulfuric acid. The mixture is stirred at intervals until all the solid which separates at the benzene-water interface has dissolved. If necessary, 50 g. of ammonium chloride is added to facilitate the decomposition of the magnesium salt, and additional benzene may be added if the amount present... 

Ethyl benzoate (15 g.) mixed with 15 c.c. of absolute ether is dropped into a Grignard solution prepared as just described from 6-4 g. of magnesium and 40 g. of bromobenzene. The conditions are the same as those observed in the preceding preparation at the end the solution is boiled for half an hour and worked up as before. Colourless prisms of triphenylcarbinol, melting point 162°, are obtained by recrystallising the solid residue from hot alcohol. Yield over 20 g. For further information about this important alcohol see p. 355. 

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