Handbook of Solvents - George Wypych - ChemTech - Ventech!

13.3 Effects of organic solvents on phase-transfer catalysis 835
Table 13.3.28. Effects of the concentrations of NaOCH 2CF 3 and kind of solvent on the
apparent intrinsic rate constants, k o,app and k a,app
Solvent
ko,app for [NaOCH2CF3] (M), (min.meq) -1
ka,app for [NaOCH2CF3] (M), (min.meq) -1
1.6 M 2.2 M 2.8 M 1.6 M 2.2 M 2.8 M
CH2Cl2 0.25 0.33 0.58 0.036 0.028 0.036
C6H5Cl 0.063 0.12 0.19 0.017 0.015 0.014
C6H5CH3 0.027 0.056 0.15 0.0055 0.006 0.011
n-C6H14 0.015 0.031 0.092 0.0008 0.0008 0.018
Data obtained from Wang and Wu; 136 50 mL of solvent, 20 mL of water, 0.0059 mol of (NPCl 2) 3, 0.18 meq of
macroporous catalyst, 20 o C, 40-80 mesh of particle
Table 13.3.29. Effects of solvents on the composition of the imbibed solvents and
swelling volume of the triphase catalyst pellet
Solvent Conditions
CH 2Cl 2
ClC 6H 5
CH 3C 6H 5
n-C 6H 14
CH2Cl2 H2O/CH2Cl2 ClC6H5 H2O/ClC6H5 2.8M NaOCH2CF3/ClC6H5 CH3C6H5 H2O/CH3C6H5 2.8M NaOCH2CF3/CH3C6H5 n-C6H5 H2O/n-C6H5 2.8M NaOCH2CF3/n-C6H5 Solvent
g
H2O
g
2.75
2.24 0.96
1.28
1.33
2.29
0.57
0.61
0.37
0
0.10
0.10
NaOCH2CF3, g
(calcd value, g)
0.73
0.50 0.34 (0.18)
0.29
0.30 0.01 (0.10)
0.30
0.15 0.01 (0.05)
Volume ratio
3.2
3.8
2.2
3.1
3.8
1.7
2.1
1.8
1
1.4
1.24
Data obtained from Wang and Wu; 136 30 mL of solvent, 0.80 meq of catalyst (1 g), 40-80 mesh of macroporous
particle, 20 o C
The overall kinetics can be divided into two steps by virtue of the presence of the two
practically immiscible liquid phases, i.e.,
(1) a chemical conversion step in which the active catalyst sites (resin with
2,2,2-trifluoroethanoxide ions) react with hexachlorocyclotriphosphazene in the organic
solvent, i.e.,
yResin +- OCH 2CF 3(s) +(NPCl 2) 3(org) →
yResin + Cl - (s) + N 3P 3Cl 6-y(OCH 2CF 3) y(org), y=1-6 [13.3.17]