Solvent effect on the α-effect for reaction of p-nitrophenyl diphenylphosphinate with N-methyl 4-methoxy benzohydroxamate ion

Shrivastava, Ashish; Ghosh, Kallol K.

doi:10.1016/j.molliq.2008.03.008

Cited by 12 publications

(1 citation statement)

References 23 publications

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“…Simanenko and co‐workers have studied a detailed kinetic study of nucleophilic cleavage of some phosphate and sulphonate esters in the presence of imidazolium surfactants bearing moieties of alpha‐nucleophiles, namely oximate hydroxamate, amidoximate group. Our research groups have also previously carried out extensive studies of reactivity in micellar media and other colloidal aggregates.…”

Section: Introductionmentioning

confidence: 99%

Kinetic study on effect of novel cationic dimeric surfactants for the cleavage of carboxylate ester

Kumar¹,

Ghosh

Barbero

et al. 2013

J of Physical Organic Chem

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Kinetic study has been performed to understand the reactivity of novel cationic gemini surfactants viz. alkanediyla,v-bis(hydroxyethylmethylhexadecylammonium bromide) C 16 -s-C 16 MEA, 2Br À (where s = 4, 6) in the cleavage of p-nitrophenyl benzoate (PNPB). Novel cationic gemini C 16 -s-C 16 MEA, 2Br À surfactants are efficient in promoting PNPB cleavage in presence of butane 2,3-dione monoximate and N-phenylbenzohydroxamate ions. Model calculation revealed that the higher catalytic effect of ethanol moiety of gemini surfactants (C 16 H 33 N + C 2 H 4 OH CH 3 (CH 2 ) S N + C 2 H 4 OH CH 3 C 16 H 33 , 2Br À , s = 4, 6) is due to their higher binding capacity toward substrate. This is in line with finding that binding constants for novel series of cationic gemini surfactants are higher than conventional cationic gemini (C 16 H 33 N + (CH 3 ) 2 (CH 2 ) S N + (CH 3 ) 2 C 16 H 33 , 2Br À , s = 10, 12), cetyldimethylethanolammonium bromide and zwitterionic surfactants, i.e. C n H 2n+1 N + Me 2 (CH 2 ) 3 SO 3 À (n = 10; SB3-10). The fitting of kinetic data was analyzed by the pseudophase model.

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Section: Introductionmentioning

confidence: 99%

Kinetic study on effect of novel cationic dimeric surfactants for the cleavage of carboxylate ester

Kumar¹,

Ghosh

Barbero

et al. 2013

J of Physical Organic Chem

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Effects on the Reactivity by Changing the Electrophilic Center from CO to CS: Contrasting Reactivity of Hydroxide, p‐Chlorophenoxide, and Butan‐2,3‐dione Monoximate in DMSO/H₂O Mixtures

Han

Buncel

2009

Chemistry A European J

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Second-order rate constants have been measured spectrophotometrically for the reactions of O-p-nitrophenyl thionobenzoate (1, PNPTB) with HO(-), butan-2,3-dione monoximate (Ox(-), alpha-nucleophile), and p-chlorophenoxide (p-ClPhO(-), normal nucleophile) in DMSO/H(2)O of varying mixtures at (25.0+/-0.1) degrees C. Reactivity of these nucleophiles significantly increases with increasing DMSO content. HO(-) is less reactive than p-ClPhO(-) toward 1 up to 70 mol % DMSO although HO(-) is over six pK(a) units more basic in these media. Ox(-) is more reactive than p-ClPhO(-) in all media studied, indicating that the alpha-effect is in effect. The magnitude of the alpha-effect (i.e., k(Ox(-) )/k(p) (-ClPhO(-) )) increases with the DMSO content up to 50 mol % DMSO and decreases beyond that point. However, the dependency of the alpha-effect profile on the solvent for reactions of 1 contrasts to that reported previously for the corresponding reactions of p-nitrophenyl benzoate (2, PNPB); reactions of 1 result in much smaller alpha-effects than those of 2. Breakdown of the alpha-effect into ground-state (GS) and transition-state (TS) effects shows that the GS effect is not responsible for the alpha-effect across the solvent mixtures. The role of the solvent has been discussed on the basis of the bell-shaped alpha-effect profiles found in the current study as well as in our previous studies, that is, a GS effect in the H(2)O-rich region through H-bonding interactions and a TS effect in the DMSO-rich media through mutual polarizability interactions.

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Unexpected Z/E isomerism of N-methyl-O-phosphothioyl benzohydroxamic acids, their oxyphilic reactivity and inertness to amines

2021

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Solvent effect on the α-effect for reaction of p-nitrophenyl diphenylphosphinate with N-methyl 4-methoxy benzohydroxamate ion

Cited by 12 publications

References 23 publications

Kinetic study on effect of novel cationic dimeric surfactants for the cleavage of carboxylate ester

Kinetic study on effect of novel cationic dimeric surfactants for the cleavage of carboxylate ester

Effects on the Reactivity by Changing the Electrophilic Center from CO to CS: Contrasting Reactivity of Hydroxide, p‐Chlorophenoxide, and Butan‐2,3‐dione Monoximate in DMSO/H₂O Mixtures

Unexpected Z/E isomerism of N-methyl-O-phosphothioyl benzohydroxamic acids, their oxyphilic reactivity and inertness to amines

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Solvent effect on the α-effect for reaction of p-nitrophenyl diphenylphosphinate with N-methyl 4-methoxy benzohydroxamate ion

Cited by 12 publications

References 23 publications

Kinetic study on effect of novel cationic dimeric surfactants for the cleavage of carboxylate ester

Kinetic study on effect of novel cationic dimeric surfactants for the cleavage of carboxylate ester

Effects on the Reactivity by Changing the Electrophilic Center from CO to CS: Contrasting Reactivity of Hydroxide, p‐Chlorophenoxide, and Butan‐2,3‐dione Monoximate in DMSO/H2O Mixtures

Unexpected Z/E isomerism of N-methyl-O-phosphothioyl benzohydroxamic acids, their oxyphilic reactivity and inertness to amines

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Effects on the Reactivity by Changing the Electrophilic Center from CO to CS: Contrasting Reactivity of Hydroxide, p‐Chlorophenoxide, and Butan‐2,3‐dione Monoximate in DMSO/H₂O Mixtures