TY - JOUR
T1 - Kinetic Study of the Dissociation of Sodium Cryptate(2,2,1)
AU - Ishihara, Koji
AU - Miura, Hiroko
AU - Funahashi, Shigenobu
AU - Tanaka, Motoharu
PY - 1988/1/1
Y1 - 1988/1/1
N2 - The rate of dissociation of sodium cryptate(2,2,1) (NaCry+) has been measured at various temperatures and pressures in dimethyl sulfoxide (Me2SO), N,N-dimethylformamide (DMF), and acetonitrile (MeCN) by using a high-pressure stopped-flow apparatus with conductometric detection. There are two reaction paths: an acid-independent path (kd1), CryNa+ → Cry + Na+, and an acid-dependent path (Kd2), CryNa+ + Hdca → CryH+ + Na+ + dca-, where Hdca is dichloroacetic acid. Activation parameters are as follows: in Me2SO, kd1/S-1 = (7.65 ± 0.05) × 10-1 (25 °C), ΔV‡dl/cm3 mol-1 = 2.1 ± 0.7, ΔH‡dl/kJ mol-1 = 70.4 ± 0.8, and ΔS‡d1/j mol-1 K-1 = -11 ± 3; in DMF, kd1/s-1 = (3.37 ± 0.03) × 10-1 (25 °C), kd2/mol-1 kg s-1 (25 °C), ΔV‡dl/cm3 mol-1 = 2.0 ± 0.2, ΔV‡d2/cm3 mol-1 = -8.8 ± 1.0, ΔH‡d2/kJ mol-1 = 73.0 ± 0.9, ΔH‡d2/kJ mol-1 = 30 ± 5, ΔS‡d1/J mol-1 K-1 = -9 ± 3, and ΔS‡d2/J mol-1 K-1 = -140 ± 20; in MeCN, kd2/mol-1 kg s-1 = 73.5 ± 0.5, ΔV‡d2/cm3 mol-1 = -16.0 ± 0.8, ΔH‡d2/kJ mol-1 =41.1 ± 1.3, and ΔS‡d2/J mol-1 K-1 = -71 ± 4. The reaction volume for the formation of NaCry+ in Me2SO has also been measured dilatometrically: ΔV° = 3.3 ± 0.4 cm3 mol-1. The reaction mechanism is discussed on the basis of these parameters.
AB - The rate of dissociation of sodium cryptate(2,2,1) (NaCry+) has been measured at various temperatures and pressures in dimethyl sulfoxide (Me2SO), N,N-dimethylformamide (DMF), and acetonitrile (MeCN) by using a high-pressure stopped-flow apparatus with conductometric detection. There are two reaction paths: an acid-independent path (kd1), CryNa+ → Cry + Na+, and an acid-dependent path (Kd2), CryNa+ + Hdca → CryH+ + Na+ + dca-, where Hdca is dichloroacetic acid. Activation parameters are as follows: in Me2SO, kd1/S-1 = (7.65 ± 0.05) × 10-1 (25 °C), ΔV‡dl/cm3 mol-1 = 2.1 ± 0.7, ΔH‡dl/kJ mol-1 = 70.4 ± 0.8, and ΔS‡d1/j mol-1 K-1 = -11 ± 3; in DMF, kd1/s-1 = (3.37 ± 0.03) × 10-1 (25 °C), kd2/mol-1 kg s-1 (25 °C), ΔV‡dl/cm3 mol-1 = 2.0 ± 0.2, ΔV‡d2/cm3 mol-1 = -8.8 ± 1.0, ΔH‡d2/kJ mol-1 = 73.0 ± 0.9, ΔH‡d2/kJ mol-1 = 30 ± 5, ΔS‡d1/J mol-1 K-1 = -9 ± 3, and ΔS‡d2/J mol-1 K-1 = -140 ± 20; in MeCN, kd2/mol-1 kg s-1 = 73.5 ± 0.5, ΔV‡d2/cm3 mol-1 = -16.0 ± 0.8, ΔH‡d2/kJ mol-1 =41.1 ± 1.3, and ΔS‡d2/J mol-1 K-1 = -71 ± 4. The reaction volume for the formation of NaCry+ in Me2SO has also been measured dilatometrically: ΔV° = 3.3 ± 0.4 cm3 mol-1. The reaction mechanism is discussed on the basis of these parameters.
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U2 - 10.1021/ic00283a010
DO - 10.1021/ic00283a010
M3 - Article
AN - SCOPUS:0001196311
VL - 27
SP - 1706
EP - 1710
JO - Inorganic Chemistry
JF - Inorganic Chemistry
SN - 0020-1669
IS - 10
ER -