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

Abstract

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.

Review on chemically bonded geminis with cationic heads: second-generation interfactants

“…Surfactant chain length can affect its interaction with substrates. Cationic gemini surfactants with longer chain length increases the cleavage of carboxylate ester [42,43]. Jiang et al [43].…”

Effects of Surfactants on the Rate of Chemical Reactions

“…The kinetics study of the acid hydrolysis of anionic N-methyl-N-nitroso-ptoluenesulfonamide (MNTS) in media containing different cationic micellar aggregates LTAB, TTAB, CTAB, andcyclodextrin ( -CD) [42] shows that the values of interaction between MNTS and surfactants increase with the chain length of surfactants. As reported [44], using cationic gemini surfactants with longer chain length increases the cleavage of carboxylate ester.…”

The use of optically active O-alkyl ester hydrochlorides of L-phenylalanine and L-tyrosine as chiral micellar media for the catalysis of diels-alder reactions

“…The use of surfactants in assisting a variety of organic reactions is highly promising for basic and applied research [10,11]. Micelle forming surfactants have been widely used as reaction medium for many important organic reactions since micelles form organized assemblies that affect the rates of chemical reactions and the position of chemical equilibrium [12,13].…”