-ILFRED P. hlILLs
3.72 [COSTRIBCTION FROM
THE
AND
CHARLES A. MACKENZIE
DEPARTMESTS O F CHEMISTRY, USIVERSITY
OF
MIAMI
ASD
Vol. i6 TULANE UNIVERSITY ]
The Application of Bond Parachors to Organosilicon Chemistry BY ALFRED P. MILLS A S D CHARLES A. MACKENZIE RECEIVEDDECEMBER 31, 1953 Using the system of organic bond parachors developed by Vogel and co-workers as a basis, the following set of silicon bond parachors has been developed: Si-C, 11.8(no F, 0 or C1 bonded to Si),9.2 ( C is aryl), 12.6 (one 0 or up t o 3 Cl's bonded t o Si), 14.2 (2 0 ' s bonded to S i ) ; Si-0, 12.7; Si-C1, 60.3; Si-I, 107.9; Si-H, 25.0 (no F, 0 or CI bonded to S i ) ; 29.1 ( 1 t o 3 0 ' s or Cl's bonded t o Si); C-C, 3 . 0 (SiEt or SiPr except SiR4 cpd.), 2.3 (SiEti and S i c 4 ) ,2.6 (SiOEt or SiOPr); C-0, 16.0 (SiOR). The probable 50r; deviation based on the 20 measured parachors used i n deriving this system is 0.437;. An average deviation of 0.50r; is obtained when this systrm i? applied to 34 measured parachors not used in deriving thi7 sy5teni.
Introduction The use of atomic parachor values for the prediction of has served along with molar refraction as a convenient tool for confirming the structure of new organic compounds. The first atomic parachor system was developed by Sugden' in One Of the most recent 'ysterns was published by Voge12 in 194% When attempts were made to extend the system to silicon compounds the Same difficulties were encountered as with atolnic refractions.3 .I the compounds studied by \Varrick4 the range of the atomic refraction for silicon as calculated from the observed molar refraction was 3.23 to 8.54. Similar calculations of atomic parachor for the co,npounds listed in Tables I11 and It' yielded values ranging from 9.0 to 54.4. I n the case of molar refractions
Experimental Materials.-Tetraethylsilane was prepared by the addition of ethylmagnesium bromide in triethylchlorosilane. The remaining compounds were obtained from Anderson Laboratories, Inc. All of the above compounds were purified by fractionation using a column packed with glass helices and having about 15 theoretical plates. Density.-The densities were determined in sealed or stoppered density bulbs by the method of MacKenzie, Mills and Scott.7 a cathetometer being used for the measurements. Refractive Index.-The refractive indices were measured with an Abbe refractometer. Measurements mere made rapidly in order to minimize errors due to oxidation and hydroll,sis. Surface Tension.-The surface tensions were determined by the capillary rise method in the double capillary type of apparatus, the two capillaries having internal diamctcrs of 0.3 and 0.53 m m . , respectively. A cathetometer was uscd the capillary rise. to The experimental data are listed in Table I .
TABLE I PROPERTIES OF ORCASOSILICOS COMPOUNDS PHYSICAL n,p. OC.
7 3 .n 120 99.4
I74 5 102 2.7.5 1,5'7.7
(CH,),SiCI
57.3
dtd
I,
"C.
0.9334 ,9227 ,9176 ,9097 ,7640 ,7542 .9,558 .9-151 ,9581 ,8500 ,6399
20.0 30.0 20.0 28.7 20.0 29.3 20.0 29.8 20.0 28.1 20.0
,8528 .8827
2,5.5 41.4
1.3964
this difficulty was overcome by S a ~ e rwho , ~ used a mixed system of group and bond refractions, a.nd by I \ ' a r r i ~ k , ~ who extended Denbigh'sj bond refraction system to organosilicon compounds. I n 1950 Vogel and co-workers6 published a set of 34 bond parachors based on the investigation of 700 liquid compounds of high purity. Some of these values are listed in Table 11.
c
S.Sugden, J . C h r m . S o c , 1177 (1921). A . I. Vogel, i b i d . . 1842 (1948). R. 0 . Sauer, THISJ O U R X A L , 68, 954 (1946). E. L . Warrick, ibid.,68, 2455 (1946). K . G . Denbigh, Tvniis. Fnvndny Suc , 96, 936 (1940). A I V o a e l , \V T. Cresswell. C. 1 Jeffery an
i,,~il,,~li." ,,,>,I i i l , ! r r c f r Y
R.iY i 1 i ) i O l
20.2 32.5 15.3 31.7 21.8 31.8 19.3 31.0 20.0 30.0 20.C 21.2
1.3~12 i.m7c1 1.8937 1.3388 1.4238 1.4210 31.8 i,-~i:-~ 41.0 1.3887 27.5
Technical proba1,lc T,iIc; error. System of \Varrick.4 sot., 120 (1931) (PO< o.7oo0, d30i 0.7579:.
(1) (2) (3) (4) (5) (6)
1 , 'C.
72!0
1,3829 1.377; 1.4019 1.3907 1.3769 1 3712
Cnlcd. based
yr
(dynedcm.)
1. o c .
21.67 =k 0.12' 20 .(I 20.75 =k .OF) 29.3 20.0 23.55 i . E 22.73 f .12 29.8 lt5.48 .09 20.0 1 4 . Z f .09 29.3 20.0 18.57 i .10 29.5 17.80 .in 20.0 18.43 =t .is 28.d 17.93 f .08 12 85 i .07 20.0 2 0 , OC 2 3 . 0 1 f .13 31.2 21.80 i . I O 11 2 20.75 .it 25.8 17.25 f . I 1 1 5 . 9 2 i .on 41 . o on densities from Sugden a n d
+
74.70
74 56
93 38
93.20
30.34 48 8!IC
30 28 '1-8 80
*
n'ilkins, J . U w m .
Results and Discussion In this research the Si-C, Si-0, Si-C1, Si-I, Si-H, C-C and C-0 bond parachors were calculated. The resulting values are given in Table I1 The parachors used in deriving this systern are listed in Table 111. The probable 50Yc deviation based on these 20 observed parachors is 0.43%. I n Table IV are listed the observed and calculated parachors for a number of organosilicon liquids not included in Table 111. The average deviation without regard to sign is 0.SG70; the median deviation is 0.485y0. (7) C A MacKenzle A P Mills and J M. Scott, THISJ U U R N A L 72 2 0 3 2 ( I ~ l i O )
.APPLICATION
*May 20, 1954
OF
BONDP.\R.~CHORS TO ORG.INOSILICON CHEMISTRY TABLE1lr
TABLE I1 BONDPARACHORS Bond
C-H
c-c
c=c
Parachor, ml./mole
2673
Bond
Voge16 17.85 C-C1 4.30 C-O(ethers) 28.5
OBSERVED PAR.4CHORS Parachor , ml./mole
57.4 12.2
This research Si-Car 9.2 Si-H(non-polar j" 25.0 Si-C(non-polnr)" 11 . 8 Si-H(po1arj" 29.1 12,O C--C(Si-R)* 3 0 Si-C(po1ar j b Si-C( R?SiO)' 14.2 C-C(SiR4)e 2.3 Si-0 12.7 C-C(Si0R)" 2.6 Si-C1 GO.3 C-O( SiOR) 16.0 Si-I 107.9 'L S o F, 0 or C1 bonded to Si. * One 0 or up to 3 Cl's bonded to Si. e 2 0 ' s bonded to Si. 1 to 3 0 ' s or Cl's bonded t o Si. 'Only for C-C bonds in E t and P r ; uqe Vogel's value for other C-C bonds in longer chains.
NO
1 2 3 4 5
ii I
8 9
10 11 12
Formula
CHB~ CzH? CgHj" CHzCH2C1 n-CaH;" CH(CHgC1)? ti-CaH~ Z-CGHU n-C7Hlj n-CsH17 n-C&, n-CloH21
Observer
'' I'
NOT
LISTEDI S TABLE 111 Dev..
Pobs
Si(OR)a 328.0 487.6 485.3 647.9 639.9 947.0 799.3 1114.1 1273.8 1434.8 1591.8 1755.4
70
Pprerl
329.0 482.2 482.2 640.4 035.4 951.8 795.4 1116.4 127R.4 1435.4 1595.4 1755.4
+o.m -1.11
-0 64 -1
16
-0.70 $0.51 -0.49 $0.12 + O . 13 $0.04 $0.23 0
MenSi( MezSiO),OSiMes f 0 . 50 ' 420.2 422.3 13 n = 0" -0.19 423.1 14 0" 422.3 e 580.1 $0.53 583.2 1 15 TABLE I11 -0.34 1 585,2 583.2 16 SELECTED LISTOF OBSERVED PARACIIORS USEDIN DERIVIXC $0.91 " 737.4 744.1 2 17 BOTDPARACHOR SYSTEM -0.16 745.3 744.1 2 18 ObDev., 900.1 +0 54 905.0 h-0 19 3 server POh PPWd % -0.14 900.3 905, 0 20 3 1 * 330.9 -0.57 329 0 E 1059.5 106R.9 50.00 4 2 " 181.6 482 2 .12 21 -0.13 4 1067.3 1065,9 3 63fi.2 635 4 .03 23 $0.78 e 1217.3 1226. 8 5 4 " 422.1 422 3 . 0 5 23 +0.27 24 1223.5 1220.8 6 5 644.5 643 R - .14 e 1381.1 R +0.48 1387.7 6 802.7 804 5 . 2 2 25 $0.15 R 1385.6 1387.7 I 261 4 ' 262.2 - .30 20 -0.44 7 1555.4 1548.6 8 ' 412.7 .17 27 413 4 -0.44 10 2040.8 2031.3 9 *b 565.3 ,565 4 . 0 2 28 2853.7 29 -0.63 2835.8 15 10 - .O1 787 4 787.5 (MeZSiO), 11 a 260.7 - .73 258 8 n = 4" 643.6 634.5 +1.43 12 299.8 299 1 - .23 30 +1.26 a 794.5 5" 804.5 13 255.0 254 6 - . I 6 31 6 4-1.85 947.8 965.4 14 209.0 210.0 $ . 4 8 32 $1.41 1110.6 1126.3 7 15 394.0 390 8 - . 8 1 33 $0.29 412.2 413.4 Si( CzHJF 16 339.4 337 2 - .65 34 17 242.2 - .41 241 2 Other measurements on compounds listed in Table 111. d 18 99.7 .30 b S . Sugden and H. Wilkins, J . Chem. SOC.,126 (1931). 100 0 B .A . Arbuzov and V. S. Vinogradova, Doklady A k a d . 19 e 182.5 182 9 .22 C N a u k . S.S.S.R., 6 0 , 799 (1948). 1%'. J . Jones, L. H . 20 e 266.4 265 8 - .23 Thomas, E. H . Pritchard and S. T. Bowden, J . Chern. a This research. S. Sugden and H . Wilkins, J . Chem. soc., 824 (1946). e M MT.. Hunter. E. L. Warrick. 1. F. Hyde and C . C. Currie,"THIS JOURNAL, 68, 2284 (f946). SOC.,126 (1931). " C . A . MacKenzie, A . P . Mills and J. M. Scott, THISJOURNAL,72, 2032 (1950). d T . G. ' H . W. Fox, P. W. Taylor and 15'. A . Zisman, Ind. Eng. Chenz., 39, 1401 (1947). 9 M . J . Hunter, J . F. Hyde, E. Pearson and P . L . Robinson, J . Chem. Soc., 736 (1934). e H . J. Emeleus, A . G. Maddock and C. Reid, ibid., 353 L . Warrick and H . J . Fletcher, THISJOURNAL,68, 667 (1946). (1941).
' '
'
r
+ + + + + +
'
' ' ' ' ' '
+ +
The predictability obtained with the above system compares favorably with that obtained using bond refractions; although the above system is somewhat more cumbersome and restricted than the bond refraction system of \ V a r r i ~ k . ~Due to the simplicity and high accuracy of refractive index measurements, the molar refraction system will usually be chosen for structure proof when a re-
fractometer is available. In difficult or questionable cases, however, the use of both systems may prove advantageous. Since accurate determinations of surface tensions are rather difficult, this system will have considerable value for calculating the surface tension of silicon compounds whose densities are known. CORAL GABLES,FLORIDA
