April 20, 1960
0
5
PHENYLACETIC
IO
I5
20
15
MINUTES.
30
35
40
45
ACID WITH KETONES
1057
50
Fig. 5.-Zero-order plot of the decomposition of intermediate I11 a t 30°, (CzH6)2A1Cl concn. 5.8 millimolar; (C5H.&TiC12 concn.: 0 , 5.8 millimolar; 0, 2.9; 0 , 1.45; A, 0.72.
ethylene, if formed, would undoubtedly have polymerized under our conditions, the amount of gas evolved using a large amount of toluene as a solvent was too great for the reaction to be exclusively one of disproportionation. Apparently the nature of the solvent and the experimental conditions have some effect on the course of the reaction. , Evidence had been presented in previous papers2v3 I that some tetravalent titanium must be present 0 IO 20 30 40 50 4 I I MUTES. for soluble catalysts derived from bis-(cyclopentadienyl) -titanium- dichloride to show the& high Fig. g.-First-order plot of the decomposition of interactivity. In an attempt to identify the active mediate I11 a t 30°, (C2H,)2A1Cl concn. 5.8 millimolar; catalytic species, a comparison was made between (C*H&TiCl2 concn.: 0 , 5.8 millimolar; 0, 2.9; 0, 1.45; the concentration of intermediate I11 and the A, 0.72. initial rate of polymerization of ethylene. This was done both during the formation of complex I11 derived from it. If our assumption is correct that and during its decomposition (see Experimental the mechanism of olefin polymerization is fundasection). As can be seen in Fig. 3 , there is a mentally the same with heterogeneous catalysts, reasonably good correlation between intermediate the active ingredient in Ziegler polymerization is I11 concentration and initial polymerization rate, an alkylated transition metal compound complexed although there is considerable scatter in the de- with a Lewis acid, such as (C2Hs)&Cl, A1CI3, composition curve. It seems reasonable to con- TiC14,TiC13 and the like. Acknowledgments.-We are indebted to Drs. clude from these results that the active catalyst in this system is complex 111, to which we have as- H.ILI. Spurlin, H.G. Tennent and H. Boardman A Imany C I ~ , stimulating discussions. signed the structure ( C S H & C ~ H ~ T ~ C ~ . C ~ H ~for or some species in equilibrium with i t or readily WILMINGTON, DEL. I
I
I
I
'
[COSTRIBCTION FROM
THE
DEPARTMENT O F CHEMISTRY, DUKE UNIVERSITY]
Condensation of Phenylacetic Acid with Certain Ketones to Form a-Phenyl-P-hydroxy Acids by Alkali Amides. Equilibrium Factors1 BY PHILLIP J. HAMRICK, J R . , ~A N D CHARLES R. HAUSER RECEIVED AEGUST31, 1959 The disodio and dilithio salts of phenylacetic acid, prepared by means of two equivalents of sodium amide or lithium amide in liquid ammonia, were condensed with benzophenone and with cyclohexanone t o form the corresponding a-phenyl@-hydroxyacids. Yields up to 93% were realized for both acids, but a metallic cation effect was observed in the condensations with cyclohexanone in which the yield was better with lithium amide than with sodium amide. The monosodium salts of the &hydroxy acids were cleaved in aqueous solution to regenerate the corresponding ketone and sodium phenylacetate. Consideration is given to the factors governing the condensation and cleavage.
It has previously been shown that phenylacetic can be alkylateda or added conjugatively to certain (1) Supported by t h e Office of Ordnance Research, U. S. Army. (2) Department of Chemistry, Wake Forest College.
a,P-unsaturated carbonyl compounds4 by means of sodium amide in liquid ammonia. Examples of (3) C . R . Hauser and W. J. Chambers, THISJ O T ~ R N A L78,4942 , (1956). (4) C. R.Hauser and M . T . T e t e n b a u m , J . Oyg. Chem.,23,1146(1968).
PHILLIP J. HAMRICK, JR.,
1958
these condensations, which involve the intermediate formation of disodio phenylacetate, are illustrated i i i Scheme A. SC~IERII~: X 2h-a”:, S:t C ~ I I B C H ~ C O OH--& CoFIiCHC0OS:t liq. S H 3
!
CF,HBCH=CHCOCJ~~
L-
-J
1
Yol. S”
The @-hydroxyacids I1 and I11 were identified by comparison of their melting points with reported values in the literature and by neutralization equivalents. ,3-Hydroxy acid I1 was also dehydrated to give a 767, yield of the a,p-unsaturated acid IV, which was’”cpc1izedto produce a 52% yield of the indenone V. These reactions appear to be useful for the syntheses of IV and V. C’hH
>
( C J Ii1.c=c -C-OO€I C6HjCH2
CsHjCHCOOH
C~HBCHCOOH
I
I
ChH,
I t has now been found that disodio- or dilithiophenylacetate (I), prepared by means of two molecular equivalents of sodium amide or lithium amide in liquid ammonia, can enter into an aldol type of condensation with certain ketones to form a-phenyl-&hydroxy acids. Thus, the condensation of the dialkali salt I with benzophenone presumably formed dialkali salt 11’, which, on acidification under appropriate conditions, gave the aphenyl-0-hydroxy acid I1 in yieds of S7-93yO (equation 1).
nr liq. S E I s ( C ~ H B ) ~ C = O Cs~%jCHC0Oh1 -+ I (a1 = :
