6427
propanes. Normally, the first aliquot of each sample, consisting of about 50% of the total, was analyzed on this column. Two or more of the other columns were then used for auxiliary purposes. (d) 30'DMS: 30-ft column of 2 5 % dimethylsulfolane on 30-50 mesh activated alumina. The order of the retention times is similar t o that of the SO'DMS, but the actual time required is much shorter. With a flow rate of 25 ml/min, it takes more than 10 hr for the elution of oxygenated compounds such as alcohols. Two more columns, a 50-ft di-n-butyl phthalate (SO'DBP) and a 50-ft tri-o-tolyl phosphate (SO'TTP),
were also used during the preliminary runs. They were discarded later because the oxygenated compounds emerged too quickly, making impossible the isolation of the individual peaks of the fluorocyclopropanes. Analysis of Mixtures from Competition Experiments. The relative reactivities of different olefins were obtained from the observed yields of the appropriate radioactive product(s) for each olefin, corrected for the mole ratio of the olefins in the mixture. The mole ratios were measured by thermal conductivity response, calibrated for each molecule, as measured during the gas chromatographic analyses.
Kinetics of the Hydroxymercuration of Olefins' Jack Halpern and H. Burnham Tinker Contribution from the Department of Chemistry, University of Chicago, Chicago, Illinois 60637. Received June 16, 1967 Abstract: The kinetics of the hydroxymercuration of 20 olefins and substituted (hydroxy, chloro, and cyano) olefins, Hgz+ >C==C< HzO + [Hg> C - C f O H I f H f , have been determined in aqueous perchloric acid solution. The rate law in each case was found to be rate = k[Hg2+][>C=C8 Reactions with Mercurous Ion. Hydroxymercuration or of up to 7.5 X l e 3 M H202.Absence of 0 2 of olefins can also be effected by reaction with mercatalysis was also confirmed for the reaction of allyl curous ion, Le. alcohol. Effect of Hydrogen Ion. The rates of hydroxymerHgz2+ >C=C< + Hz0 +tHgPC-CfOH]+ curation of the following olefins were found to be inH+ HgO) (7) dependent of the H+ concentration over the ranges in(20) S. Hietanen and L. G. SillCn, Acta Chem. Scand., 5, 747 (1952). dicated: ethylene (0.01-0.1 M H+) ; trans-2-butene The values of pK, reported in this paper were determined at an ionic (0.001-0.1 M H+); I-penten-4-01 (0.01-0.1 M H+); strength of 0.5 and it is possible that their correction to the lower ionic strength (0.1) used by us would result in some modification of our conI-cyclohexen-3-ol(O.005-0.1M H+).
+
(19) A. Brook, R. Donovan. and G. F. Wright, Can. J . Chem., 536 (1953).
Journal of the American Chemical Society
+ +
clusions based on them. (21) C. Perrin and F. H. Westheimer, J. Am. Chem. Soc., 85, 2773 (1963).
1 89:25 / December 6 , 1967
643 1 Table 111. Activation Parameters
Table 11. Summary of Rate Constants ~
Olefin Ethylene
Propylene 1-Butene Isobutene cis-2-Butene
trans-2-Butene
Cyclohexene Allyl alcohol
2-Methyl allyl alcohol 1-Buten-3-01
1-Buten-4-01
1-Penten- 3-01
1-Penten-4-01
1-Penten-5-01 1-Hexen-6-01 1-Cyclohexen-3-01
cis-2-Buten-1-01 trans-2-Buten- 1-01 cis-2-Butene-1&diol Allyl chloride Allyl cyanide
Temp, 'C 11 20 25 32 37 25 25 25 18 25 32 37 18 25 32 37 25 4 11 18 25 32
25 4 11 18 25 25 32 4 11 18 25 32 3 11 18 25 25 3 11 18 25 32 25 25 3 11 18 25 25 25 25 25 25 25 25
k , M-I sec-l
AH* (& 0.5), kcal/mole AS* (kl), eu
(I
2 . 2 x 103 4.0 x 103 5.1 x 103 7.6 x 103 9 . 8 x 103 (1 f 0.2) x l o b * (8 f 2) X 104b >106C 3 . 9 x 103 5.8 x 103 8 . 8 X lo3 12 x 103 0 . 9 x 103 1 . 7 x 103 2 . 5 x 103 3.3 x 103 (5 1) x 103 2.4 X lo2 4 . 3 x 102 6.5 X lo2 11.2 x 102 18 X lo2 (3 f 2) x 104 0.54 X l o 2 0.73 X lo2 1 . 3 X lo2 2 . 6 X lo2 2 . 8 X lOzd 5 . 3 x 102 2 . 4 x 103 3 . 6 x 103 5.6 x 103 8.4 x 103 11 x 103 0.30 X 102 0.52 X lo2 0.96 X lo2 1 . 4 X lo2 1 . 5 X 102d 1 . 4 x 103 2 . 3 x 103 3 . 7 x 103 6 . 1 x 103 9 . 6 x 103 >106C -1 x 105 0.86 X 102 1 . 6 X 102 2 . 7 X lo2 4 . 3 x 102 (4.4 rt 0.8) x 1028 (2.0 rt 0.4) X l o z e 12 13d 11.5' 1Id 4.3d
Rate constants measured in solutions containing 0.01 M HCIOl unless otherwise stated. Ionic strength maintained at 0.10 with NaClO4. * Low precision due to very fast reaction. Too fast to measure; lower limit based on assumption of second-order kinetics. Rate based on H+ formation using cresol red indicator. $Derived from rate measurements on a series of mixtures of cis- and trans-2-buten-1-01 of known compostion. f In D20. a
The rates of the reactions of 1-buten-3-01 and cis-2butene-I ,4-diol with Hgz2- were determined in solutions of mercurous perchlorate equilibrated with metallic mercury. The apparent rate constant (defined by rate/[Hgz2+]>C=C
