ON THE APPLICATIONS OF GRIGNARD'S REACTION, 279 
extent of their application may be ascribed. Many of the reactions in 
which they play a part require weeks, or even months, for their com- 
pletion, and the yields of the resulting compounds are often far from 
satisfactory. Magnesium organic compounds; on the other hand, are so 
much more easily prepared than zine alkyl compounds ; they are not 
inflammable on exposure to the atmosphere, and they can be manipulated 
with such facility that the older methods, depending on the use of zinc 
compounds, have been superseded. Not only is this the case, but 
Grignard’s reagent has been applied for the preparation of carbon 
compounds by methods which earlier investigators did not have at their 
disposal. 
Grignard was not the first to attempt the substitution of magnesium 
alkyl for zinc alkyl compounds for synthetic purposes. Fleck,' working 
in Lothar Meyer’s laboratory, showed in 1893 that magnesium methyl 
interacts with acetyl chloride to form trimethylcarbinol ; but, in spite of 
the reactivity of magnesium methyl, the method presented no advantages 
over the use of zinc alkyls ; in fact it was less convenient, since magnesium 
alkyls are neither volatile nor soluble in the ordinary organic solvents. 
In a paper which paved the way for the Grignard reaction, Barbiér 2 
showed that the zinc in Saytzew’s reaction may be replaced by magnesium, 
and that it is not necessary actually to isolate magnesium methyl in 
order to use it subsequently for synthetic purposes. It was possible to 
obtain dimethylheptenol, (CH;),C : CH .CH,. CH, . C(OH)(CH;),, from 
methylheptenone, (CH;),C : CH . CH, . CH, . CO. CH;, by adding 
methyl iodide to an ethereal solution of the ketone in the presence of 
magnesium. 
Grignard * was led to study magnesium organic compounds in con- 
sequence of this work of Barbier, and of an observation of E. Frankland 
and Wanklyn that the zine compound Zn(CH3;).,(C,H;),;0 is formed 
when methyl iodide is heated with zinc and anhydrous ether in a sealed 
tube. 
In the present account of Grignard’s action the more important 
applications will be indicated, but no attempt will be made to give a 
complete réswmé of all the work carried out in this field. Section I. deals 
with the various types of synthesis accomplished by aid of Grignard’s 
reagent, Section IT. with some practical details, and Section IIT. with the * 
theoretical aspect of the subject. 
Section I. 
Alcohols and Phenols. 
(a) Secondary alcohols.—A large number of secondary alcohols have 
been obtained from aldehydes or from formic esters by the method already 
indicated in the Introductory Section. 
(b) Zertiary alcohols.—The mode of formation of tertiary alcohols 
from ketones, acid chlorides, acid anhydrides, and esters respectively has 
also been referred to. A large amount of work has been done in this 
particular branch, not only by Grignard himself, but, amongst others, 
by Acree, Béhal, Klages, W. H. Perkin, jun., Sachs, and Zelinsky. 
' Annalen, 1893, 276, 134. Compare Lohr, ihid., 1890, 261, 72. 
2 Compt. rend., 1899, 128, 110. 
% Revue générale des Sciences pures et appliquécs, 1903, 14, 1041. 
