Abstract
The kinetics of the hydride-transfer reactions from bis[4- (dimethylamino)phenyl] methane (MH2), bis[4(dimethylamino)phenyl] methoxy methane (MHOMe), Leuco Malachite Green (MGH) and Leuco Crystal Violet (CVH) to 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) have been investigated spectrophotometrically by means of the stopped-flow technique. The negative activation enthalpies were obtained for the hydride-transfer reactions from MH2, MHOMe and MGH to DDQ in dichloromethane. These negative activation enthalpies suggest that the charge-transfer (CT) complexes are true intermediates in the hydride-transfer reactions from these donors to DDQ, as previously pointed out for MH2-DDQ system in trichloroethane. The formation of charge-transfer complexes between MH2, MHOMe, MGH and CVH and p-chloranil (CA) were observed in EPA (ethylether-pentane-ethanol) at low temperatures. The oxidation potential (E(ox)/°) of MHOMe, MGH and CVH were estimated using the linear correlation between the CT transition energy and the E(ox)/°value for the known CT complexes between CA and N,N-dimethylaniline derivatives. The rates were found to be correlated to the E(ox)/°values of the donors.
| Original language | English |
|---|---|
| Pages (from-to) | 833-837 |
| Number of pages | 5 |
| Journal | Physical Chemistry Chemical Physics |
| Volume | 1 |
| Issue number | 5 |
| DOIs | |
| Publication status | Published - Mar 1 1999 |
Fingerprint
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Atomic and Molecular Physics, and Optics
Cite this
Mechanism of hydride transfer reaction from 4-(dimethylamino)phenyl methane derivatives to 2,3-dichloro-5,6-dicyano-p-benzoquinone. / Yamamoto, Shunzo; Sakurai, Tetsuo; Yingjin, Liu; Sueishi, Yoshimi.
In: Physical Chemistry Chemical Physics, Vol. 1, No. 5, 01.03.1999, p. 833-837.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Mechanism of hydride transfer reaction from 4-(dimethylamino)phenyl methane derivatives to 2,3-dichloro-5,6-dicyano-p-benzoquinone
AU - Yamamoto, Shunzo
AU - Sakurai, Tetsuo
AU - Yingjin, Liu
AU - Sueishi, Yoshimi
PY - 1999/3/1
Y1 - 1999/3/1
N2 - The kinetics of the hydride-transfer reactions from bis[4- (dimethylamino)phenyl] methane (MH2), bis[4(dimethylamino)phenyl] methoxy methane (MHOMe), Leuco Malachite Green (MGH) and Leuco Crystal Violet (CVH) to 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) have been investigated spectrophotometrically by means of the stopped-flow technique. The negative activation enthalpies were obtained for the hydride-transfer reactions from MH2, MHOMe and MGH to DDQ in dichloromethane. These negative activation enthalpies suggest that the charge-transfer (CT) complexes are true intermediates in the hydride-transfer reactions from these donors to DDQ, as previously pointed out for MH2-DDQ system in trichloroethane. The formation of charge-transfer complexes between MH2, MHOMe, MGH and CVH and p-chloranil (CA) were observed in EPA (ethylether-pentane-ethanol) at low temperatures. The oxidation potential (E(ox)/°) of MHOMe, MGH and CVH were estimated using the linear correlation between the CT transition energy and the E(ox)/°value for the known CT complexes between CA and N,N-dimethylaniline derivatives. The rates were found to be correlated to the E(ox)/°values of the donors.
AB - The kinetics of the hydride-transfer reactions from bis[4- (dimethylamino)phenyl] methane (MH2), bis[4(dimethylamino)phenyl] methoxy methane (MHOMe), Leuco Malachite Green (MGH) and Leuco Crystal Violet (CVH) to 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) have been investigated spectrophotometrically by means of the stopped-flow technique. The negative activation enthalpies were obtained for the hydride-transfer reactions from MH2, MHOMe and MGH to DDQ in dichloromethane. These negative activation enthalpies suggest that the charge-transfer (CT) complexes are true intermediates in the hydride-transfer reactions from these donors to DDQ, as previously pointed out for MH2-DDQ system in trichloroethane. The formation of charge-transfer complexes between MH2, MHOMe, MGH and CVH and p-chloranil (CA) were observed in EPA (ethylether-pentane-ethanol) at low temperatures. The oxidation potential (E(ox)/°) of MHOMe, MGH and CVH were estimated using the linear correlation between the CT transition energy and the E(ox)/°value for the known CT complexes between CA and N,N-dimethylaniline derivatives. The rates were found to be correlated to the E(ox)/°values of the donors.
UR - http://www.scopus.com/inward/record.url?scp=0033105195&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0033105195&partnerID=8YFLogxK
U2 - 10.1039/a809358j
DO - 10.1039/a809358j
M3 - Article
AN - SCOPUS:0033105195
VL - 1
SP - 833
EP - 837
JO - Physical Chemistry Chemical Physics
JF - Physical Chemistry Chemical Physics
SN - 1463-9076
IS - 5
ER -