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Titolo:
Structure-reactivity correlations in the aminolysis of aryl dithiomethyl- and dithiophenylacetates with anilines in acetonitrile
Autore:
Oh, HK; Kim, SK; Lee, HW; Lee, I;
Indirizzi:
Inha Univ, Dept Chem, Inchon 402751, South Korea Inha Univ Inchon South Korea 402751 ept Chem, Inchon 402751, South Korea Chonbuk Natl Univ, Dept Chem, Chonju 560756, South Korea Chonbuk Natl Univ Chonju South Korea 560756 , Chonju 560756, South Korea
Titolo Testata:
JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2
fascicolo: 9, , anno: 2001,
pagine: 1753 - 1757
SICI:
1472-779X(200109):9<1753:SCITAO>2.0.ZU;2-J
Fonte:
ISI
Lingua:
ENG
Soggetto:
NUCLEOPHILIC-SUBSTITUTION REACTIONS; CROSS-INTERACTION CONSTANTS; MECHANISM; KINETICS; BENZYLAMINES; DISPLACEMENT;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
35
Recensione:
Indirizzi per estratti:
Indirizzo: Lee, I Inha Univ, Dept Chem, Inchon 402751, South Korea Inha Univ InchonSouth Korea 402751 m, Inchon 402751, South Korea
Citazione:
H.K. Oh et al., "Structure-reactivity correlations in the aminolysis of aryl dithiomethyl- and dithiophenylacetates with anilines in acetonitrile", J CHEM S P2, (9), 2001, pp. 1753-1757

Abstract

The kinetics and mechanism of the anilinolysis (XC6H4NH2) of dithio esters, RC(=S)SC(6)H(4)Z with R = C2H5 and C6H5CH2 are investigated in acetonitrile at 45.0 degreesC. By,application of various structure-reactivity correlations, selectivity parameters rhox, betax, rhoz, betaz and rho xz are determined. The reactions are predicted to proceed stepwise with rate-limiting expulsion of the ArS- group. The dithio ester with R=C2H5 exhibits the fastest rate and the largest positive rho xz value; this is interpreted to result from the strongest electron donating ability of the ethyl group in the intermediate and a crowded tetrahedral intermediate and transition state in which the nucleophile (X) and leaving group (Z) are in close proximity due to the bulky C2H5 group: Much faster rates are observed for the thiocarbonyl(C=S) rather than carbonyl (C=O) esters in the stepwise nucleophilic substitution reactions, which may be ascribed to the lower pi*(C-S) and sigma*(C-LG) levels than those of the corresponding antibonding levels in the carbonyl esters. The normal kinetic isotope effects, k(H)/k(D) > 1.0, involving deuterated anilines suggest concurrent proton transfer with the expulsion of the ArS- leaving group in a four-center hydrogen bonded transition state.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 14/07/20 alle ore 22:55:33