3250
N. C . BAENZICER A N D J. J. HECENBARTH
of chloride ion as the reaction proceeded, four chlorides being released per palladous ion reaction. Two runs were made in the presence of finely divided palladium metal. T h e rate was unaffected. The following form was assumed in calculating the equilibrium constant K
K
=
Yol. S(i
where
[ P d + 2 ]= [I]
+ [PdC14-2]and k2
=
k'K [Cl - 1 2 [H i ~
j
The solution of this equation for a conTtant voluriic re;tctor is
[(PdCl,C2H,)-] [Cl-] ' [ P c I C I ~ -[C,H,] ~]
T h e net ethylene uptake was converted t o moles of complex and this subtracted from the total palladous ion concentration to give [PdC14-2]. T h e value of [Cl-] was theti equal to total chloride - 3 [( PdCI&HI) -1 - 4 [ PdC14-2] . Constant Volume Reactor.-The constant volurne reactor was essentially a 250-ml. florence flask connected to a mercury capillary manometer. T h e flask was creased to increase the stirring efficiency of the magnetic stirring bar. An outlet equipped with stopcock was used t o transfer gas into the apparatus or t o pull a vacuum. The volume of the reactor was found to be 253.8 ml. by nieasuring the pressure before and after the injection of a weighed amount of mercury. T h e reactions were run a t a n ethylene pressure of about 70 rnm. Since a t this pressure the concentration of complex is small, eq. 2 can be written
(a
log
+ P)f'[Pd+21 j + j ~ i-iij +
p i E q i j o - - 2] was obtained by the reaction of trnns-[Pt(CjHI1S)2C1P1 M) with S a S O ? (lo-' J f ) a t 30" in methanol, containing 10-2 JI toluenesulfonic acid, for 4 days. The compound was recrystallized from methanol, m . p . 258-260'. Anal. Calcd. for C 1 ~ H s 2 S a 0 4 PSt :, 12.25. Found: S ,12.1. trans-[Pt(CjH11S)2(S\;3)2] was obtained by the reaction of trans[Pt(CjHllS)2C12] ( l o w 3Jf) with SaSB ( 5 X 10-2 JI) in methanol a t 30" for 4 days. The product was recrystallized from methanol, m.p. 172-173". Anal. Calcd. for ClaHnS&: S , 2 4 . 9 . Found: S , 24.4.
226 (1964). (2) J. C h a t t , L. A. Ducanson, and L. M . Venanzi, (1955).
J. Chem. Sac., 4 4 6 1
(3) C. Enebuske, J . prakl. Chem., 3 8 , 358 (1888). (4) D. S . Tarbell and C. Weaver, J . A m . Chem. Soc., 63, 2941 (1941)
