Acid chloride, alcohols from Grignard reaction

The mechanism of this Grignard reaction is similar to that of L1AIH4 reduction. The first equivalent of Grignard reagent adds to the acid chloride, loss of (T from the tetrahedral intermediate yields a ketone, and a second equivalent of Grignard reagent immediately adds to the ketone to produce an alcohol. 

Reaction XLIII. (a) Formation of Esters by the action of Acid Anhydrides or of Acid Chlorides on an Alcohol in the presence of Magnesium Alkyl Halide (Grignard). (B., 39, 1738.)—This application of the Grig-nard reaction to the preparation of esters is of theoretical rather than practical interest as illustrating the wide applicability of this many-sided reaction. The steps in the synthesis will be clear from the examples given they are somewhat different from the usual phases of a Grignard reaction. 

Alcohols can also be obtained from epoxides, aldehydes, ketones, esters, and acid chloride as a consequence of C-C bond formation. These reactions involve the addition of carbanion equivalents through the use of Grignard or organolithium reagents. 

Acetic formic anhydride has been prepared by the reaction of formic acid with acetic anhydride2 3 and ketene,4,5 and of acetyl chloride with sodium formate.6 The present procedure is essentially that of Muramatsu.6 It is simpler than others previously described and gives better yields. It is easily adapted to the preparation of large quantities, usually with an increase in yield. Acetic formic anhydride is a useful intermediate for the formyl-ation of amines,3,7 amino acids,8,9 and alcohols,2,10 for the synthesis of aldehydes from Grignard reagents,11 and for the preparation of formyl fluoride.12... 

Tertiary aromatic alcohols are also prepared by the Grignard reaction from esters or acid chlorides of aromatic acids. 

Grignard reagents themselves react readily with acid chlorides, but the products are usually tertiary alcohols these presumably result from reaction of initially formed ketones with more Grignard reagent. (If tertiary alcohols are desired, they are better prepared from esters than from acid chlorides. Sec. 20.21.) Organocadmium compounds, being less reactive, do pot react with ketones. 

It is possible that the ketone product formed by reaction of a Grignard with an acid chloride or anhydride is. css reactive than those starting materials. If so, significant amounts of the ketone product can be isolated, but the yields are often low. With esters and amides, the ketone product is usually more reactive, very little ketone 1 isolated from the reaction mixture, and the ketone reacts further to form a tertiary alcohol. If a large excess... 

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