Ester with Grignard reagents

Esters can react with Grignard reagents (two equivalents) to form tertiary alcohols. See the following example. 

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Cleavage of acetals or ortho esters with Grignard reagents... 

Z)-)3-substituted cynnamic esters are formed with retention of the configuration, by the coupling reaction of Z-)3-ayltelluro cynnamic esters with Grignard reagent in the presence ofCul. ... 

P. O. Saperstein and J. C. Shivers Types of Reactions of Carboxylic Esters with Grignard Reagents. J. Amer. chem. Soc. 70, 606 (1948). 

Reduction of acetals or ortho esters 0-80 Reduction of epoxides 0-92 Cleavage of acetals or ortho esters with Grignard reagents... 

The reaction of esters with Grignard reagents and with lithium aluminum hydride, both useful in the synthesis of alcohols, were described earlier. They are reviewed in Table... 

Reaction of an ester with Grignard reagent produces a tertiary alcohol, not a ketone. 

Conversion of esters to secondary alcohols. The reaction of esters with Grignard reagents results mainly in tertiary alcohols, which arc formed by way of an intermediate ketone. Direct conversion of an ester to a secondary alcohol is possible by reaction with a Grignard reagent (2 equiv.) and lithium boroh dridc (0.5 equiv.). which reduces the intermediate ketone much more rapidly than it does the ester. 

Due to the higher oxidation level cyclopropylcarbinyl-homoallyl rearrangement (see also Section IV.C) of oxycyclopropanes gives, y-unsaturated carbonyl compounds. This feature has been discovered by Julia and coworkers, who reacted certain esters with Grignard reagents or LiAlH4. The corresponding cyclopropyl carbinol opens under acidic conditions to j5,y-unsaturated aldehydes (equation This conversion also works for... 

Esters, under appropriate conditions, undergo hydrolysis. This reaction is the reverse of esterification as shown in the equation on page 207. Esters react with aqueous or alcoholic ammonia to form amides. A number of reactions of esters are due to activity of the carbonyl group and the adjacent a-hydrogen atoms. The reaction of esters with Grignard reagents to form ketones or tertiary alcohols, and the various condensations, are examples of this type of reaction. 

Reaction of Esters with Grignard Reagents Esters and lactone react with 2 equivalents of a Grignard reagent to yield a tertiary alcohol in which two of the substituents are identical (Section 17.6). The reactioo occurs by the usual nucleophilic substitution mechanism to give an intermediate ketone, which reacts further with the Grignard reagent to yield a tertiary alcohol. ... 

Some transformations constitute examples of more than one of these classes. For example, the reaction of esters with Grignard reagents gives alcohols in what is a substitution and an addition reaction. Remember that classification schemes are created by people. A compound does not stop and worry about whether a particular reaction fits within the boundaries of human classification schemes before it undergoes the reaction. 

The procedure for the reaction of this ester with Grignard reagents has now been published.1... 

IV. Reactions of Trivalent Phosphorus Esters with Grignard Reagents. 34... 

Reaction of Esters with Grignard Reagents Synthesis of Tertiary Alcohols 836... 

TABLE 19.5 Reactions of Esters with Grignard Reagents and with Lithium Aluminum Hydride... 

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