Triethyl carbinol

Now run in a solution of 52 g. (53-5 ml.) of pure diethyl carbonate (1) in 70 ml. of anhydrous ether, with rapid stirring, over a period of about one hour. A vigorous reaction sets in and the ether refluxes continually. When the diethyl carbonate has been added, heat the flask on a water bath with stirring for another hour. Pour the reaction mixture, with frequent shaking, into a 2 litre round-bottomed flask containing 500 g. of crushed ice and a solution of 100 g. of ammonium chloride in 200 ml. of water. Transfer to a separatory funnel, remove the ether layer, and extract the aqueous solution with two 176 ml. portions of ether. Dry 

The following tertiary alcohols may be prepared from the appropriate Grignard reagent and diethyl carbonate in yields of 75-80 per cent. 

Dimethyl ethyl carbinol (2-methy 1-2-butanol or er .-amyl alcohol), CH3CHjCOH(CH3).2. From ethyl propionate and methyl magnesium iodide. Collect the tertiary alcohol at 100-102°. 

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The ether is distilled from the combined extracts and the crude triethyl carbinol is dried with 10 g. of anhydrous potassium carbonate. The alcohol is then distilled at atmospheric pressure, and the portion (80-90 g.) boiling at 139-1420 is collected. The low-boiling distillate is treated with 5 g. of anhydrous potassium carbonate, filtered and redistilled, whereby another portion (about 25 g.) of triethyl carbinol boiling at 139-1420 is obtained. The process is repeated once, or twice if necessary, and an additional 20 g. is collected (Note 5). The total yield is 125-135 g. (82-88 per cent of the theoretical amount) (Note 6). Triethyl carbinol is a viscous liquid with a penetrating, camphor-like odor. 

The ether used for extraction may be obtained by distilling the ether from the triethyl carbinol solution. 

Triethyl carbinol has been prepared by the action of zinc on a mixture of ethyl iodide and diethyl ketone 1 by the action of magnesium on ethyl bromide in diethyl ketone solution 2 as a by-product in the reaction between ethylmagnesium bromide and carbon oxysulfide 3 by the action of ethylmagnesium bromide on ethyl propionate 4 by the action of ethylmagnesium bromide on ethyl chloroformate 5 and by the action of ethyl-magnesium bromide on ethyl cyanoformate.6... 

In order to examine the last step proposed in the Sn2 mechanism for the decomposition of tetramethylammonium hydroxide, the decomposition of several tetramethylammonium alkoxides — in particular tetramethylammonium methoxide — were investigated 109). The decomposition of mixtures of solid tetramethylammonium bromide with potassium methoxide, rf-butoxide and triethyl carbinolate were carried out at 200 °C, in the absence of solvent. In all cases the predominant product was the ether, but a 20—25% yield of the corresponding alcohol was observed, indicating that some proton abstraction must have occurred. The steric requirement of the base did not affect the overall yield and the relative amount of ether and alcohol that was obtained. 

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