Evaluation of Electronic Effects in the Solvolyses of p-Methylphenyl and p-Chlorophenyl Chlorothionoformate Esters
Table 1
Specific rates of solvolysis (k) of 6 and 7 in several binary solvents at 25.0°C and literature values for and .
Solvent
(6 @ 25.0°C; 105 , s-1)
(7 @ 25.0°C; 105 , s-1)
100% MeOH
11.3 ± 0.9
29.9 ± 2.2
0.17
−1.2
90% MeOH
22.5 ± 1.5
47.9 ± 1.6
−0.01
−0.20
80% MeOH
30.1 ± 1.6
64.5 ± 1.1
−0.06
0.67
100% EtOH
1.51 ± 0.17
15.9 ± 1.0
0.37
−2.50
90% EtOH
3.02 ± 0.24
26.4 ± 1.1
0.16
−0.90
80% EtOH
4.30 ± 0.12
39.6 ± 0.8
0.00
0.00
70% EtOH
6.64 ± 0.19
−0.20
0.80
90% Acetone
0.327 ± 0.018
0.870 ± 0.015
−0.35
−2.39
80% Acetone
0.577 ± 0.029
1.85 ± 0.25
−0.37
−0.80
70% Acetone
0.980 ± 0.026
2.78 ± 0.16
−0.42
0.17
97% TFE (w/w)
1.07 ± 0.07
0.0456 ± 0.0012
−3.30
2.83
90% TFE (w/w)
1.49 ± 0.17
0.354 ± 0.024
−2.55
2.85
80% TFE (w/w)
2.12 ± 0.12
−2.22
2.90
50% TFE (w/w)
1.88 ± 0.17
−1.73
3.16
80T-20E
0.399 ± 0.012
0.332 ± 0.015
−1.76
1.89
60T-40E
0.626 ± 0.009
1.03 ± 0.04
−0.94
0.63
40T-60E
1.16 ± 0.05
3.26 ± 0.15
−0.34
0.48
20T-40E
2.34 ± 0.12
10.6 ± 0.4
0.08
−1.42
97% HFIP (w/w)
24.3 ± 1.2
1.92 ± 0.06
−5.26
5.17
90% HFIP (w/w)
23.0 ± 0.9
1.39 ± 0.13
−3.84
4.31
70% HFIP (w/w)
18.2 ± 1.3
−2.94
3.83
50% HFIP (w/w)
0.888 ± 0.015
−2.49
3.80
ubstrate concentration of ca. 0.0052 M; binary solvents on a volume-volume basis at 25.0°C, except for TFE-H2O and HFIP-H2O solvents which are on a weight-weight basis. T-E are TFE-ethanol mixtures. ith associated standard deviation. eferences [19, 20]. eferences [21–23].
