Mechanism of solvolysis of substituted benzyl chlorides in aqueous ethanol

Denegri, Bernard; Matić, Mirela; Vaško, Monika

doi:10.1016/j.tet.2021.132548

Cited by 2 publications

(3 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

Section: Resultsmentioning

confidence: 99%

“…Different research groups have demonstrated previously that the molecularity (i.e., the mechanism) of solvolyses reactions of a series of related substrates can be determined by analyzing the slopes (i.e., ρ + values) of both Hammett-Brown and Yukawa-Tsuno plots. 24,[41][42][43][44] Since the basics rides (ranging from 0.85 to 1.11) 25 and bromides (ranging from 0.93 to 1.01) 25 in various hydroxylic solvents and aqueous mixtures shows approximately equal susceptibility of the solvolytic reactivity of these series of substrates to a substituent effect. The high s f values unequivocally confirm that solvolyses of benzhydryl diphenylphosphinates proceed through a carbocation intermediate (i.e., by the S N 1 mechanism).…”

Section: Application Of Log K(25 • C) Versus E F Correlations In Dete...mentioning

confidence: 99%

“…Accordingly, it can be generally concluded that secondary benzylic Ar/Rdisubstituted phosphinates and, consequently, tertiary benzylic Ar/R-disubstituted phosphinates solvolyze via the S N 1 mechanism, in which alkyl-oxygen fission occurs. On the other hand, it has been shown previously that the molecularity of solvolyses of substituted benzyl substrates depends upon both the nature of substituents on the phenyl ring and ability of a leaving group attached to the benzylic carbon [41][42][43][44][45] ; thus, further kinetic investigations are to be performed in order to determine the mechanism of solvolyses of benzyl Ar/R-disubstituted phosphinates (as well as of other esters bearing substituted benzyl electrofuges).…”

Section: Application Of Log K(25 • C) Versus E F Correlations In Dete...mentioning

confidence: 99%

See 2 more Smart Citations

Nucleofugality of diphenylphosphinate and kinetic stabilities of secondary and tertiary benzylic diphenylphosphinates in aqueous solvents

Matić

Denegri

Tarandek

et al. 2022

Int J of Chemical Kinetics

Self Cite

View full text Add to dashboard Cite

First‐order rate constants for solvolyses of variously substituted benzhydryl diphenylphosphinates in four aqueous solvents have been measured conductometrically in order to investigate leaving group ability of diphenylphosphinate (DPP), that is, to determine corresponding nucleofuge‐specific parameters (Nf and sf) according to the correlation equation log k (25°C) = sf(Ef + Nf). DPP is the first of phosphorus leaving groups included on the Nf nucleofugality scale which presently covers a reactivity range of 15 orders of magnitude. Application of log k (25°C) versus Ef plots has unequivocally shown that benzhydryl diphenylphosphinates solvolyze in hydroxylic solvents by the SN1 mechanism. As the abovementioned equation and corresponding reactivity parameters can also be employed for predicting heterolytic reactivity of substrates in various solvents, the range of kinetic stability of secondary and tertiary benzylic diphenylphosphinates toward heterolysis has been examined in terms of reaction half‐lives. Further, in order to investigate the origin of stability of the DPP anion and, consequently, the ability of the DPP leaving group, quantum mechanical calculations and the Natural Bond Orbital (NBO) analysis were performed at the M06‐2X/6‐311+G(3df,3pd) level of theory using the SMD solvation model. The NBO analysis has revealed that negative hyperconjugation plays a dominant role in delocalizing the anionic charge in disubstituted phosphinate leaving groups.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Application Of Log K(25 • C) Versus E F Correlations In Dete...mentioning

confidence: 99%

Section: Application Of Log K(25 • C) Versus E F Correlations In Dete...mentioning

confidence: 99%

See 1 more Smart Citation

Nucleofugality of diphenylphosphinate and kinetic stabilities of secondary and tertiary benzylic diphenylphosphinates in aqueous solvents

Matić

Denegri

Tarandek

et al. 2022

Int J of Chemical Kinetics

Self Cite

View full text Add to dashboard Cite

show abstract

Triton-X-100 as an Organic Catalyst for One-Pot Synthesis of Arylmethyl-H-phosphinic Acids from Red Phosphorus and Arylmethyl Halides in the KOH/H2O/Toluene Multiphase Superbase System

et al. 2023

View full text Add to dashboard Cite

Triton-X-100, a polyethylene glycol 4-(tert-octyl)phenyl ether, has been found to be an active micellar organic catalyst for the one-pot selective synthesis of arylmethyl-H-phosphinic acids in up to 65% yields by the direct phosphinylation of arylmethyl halides with red phosphorus in the KOH/H2O/toluene multiphase superbase system. The catalyst demonstrates a good recyclability. As a result, an expeditious method for the chemoselective synthesis of arylmethyl-H-phosphinic acids—versatile sought-after organophosphorus compounds—has been developed. The synthesis is implemented via direct alkylation/oxidation of red phosphorus with arylmethyl halides, promoted by superbase hydroxide anions using Triton-X-100 (a commercial off-the-shelf organic recyclable micellar catalyst). The reaction comprises the hydroxide anions-assisted disassembly of Pred 3D polymer molecules triggered by the separation from the potassium cation in ordinary crown-like micelles to produce polyphosphide anions in aqueous phase. Further, polyphosphide anions are alkylated with arylmethyl halides in organic phase in the presence of the catalytic Triton-X-100 reverse micelles and alkylated polyphosphide species undergo the double hydroxylation. The advantages of the strategy developed include chemoselectivity, benign and accessible starting reagents, catalyst recyclability, and facile one-pot implementation.

show abstract

Mechanism of solvolysis of substituted benzyl chlorides in aqueous ethanol

Cited by 2 publications

References 72 publications

Nucleofugality of diphenylphosphinate and kinetic stabilities of secondary and tertiary benzylic diphenylphosphinates in aqueous solvents

Nucleofugality of diphenylphosphinate and kinetic stabilities of secondary and tertiary benzylic diphenylphosphinates in aqueous solvents

Triton-X-100 as an Organic Catalyst for One-Pot Synthesis of Arylmethyl-H-phosphinic Acids from Red Phosphorus and Arylmethyl Halides in the KOH/H2O/Toluene Multiphase Superbase System

Contact Info

Product

Resources

About