The Ba(II) complex of a crown ether bearing a sulphydryl side-arm as turnover catalyst of ester cleavage

被引：6

作者：

Cacciapaglia, R ^{[1
]}

Mandolini, L ^{[1
]}

Spadola, F ^{[1
]}

机构：

[1] UNIV ROMA LA SAPIENZA,DIPARTIMENTO CHIM,I-00185 ROME,ITALY

来源：

TETRAHEDRON | 1996年 / 52卷 / 26期

关键词：

D O I：

10.1016/0040-4020(96)00434-6

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

When activated by barium(II), 18-mercaptometyl-1,4,7,10,13,16-hexaoxacyclononadecane acts as turnover catalyst in the methanolysis of p-nitrophenyl acetate (pNPOAc) under slightly basic conditions in CH3CN-CH3OH 9:1 (v/v). The function of the complexed barium ion is to enhance the nucleophilicity of the pendant SH group towards the acetyl group of the ester. and to assist as a built-in electrophile the subsequent transfer of the acetyl group from the acetylated intermediate to the solvent. Besides the above double displacement mechanism of ester cleavage, a direct metal-ion assisted methanolysis involving reaction of pNPOAc with the ternary complex (5 BaOMe)(+) has been detected. (C) 1996 Elsevier Science Ltd

引用

页码：8867 / 8876

页数：10

共 20 条

[1]

BENDER ML, 1971, MECH HOMOGENEOUS CAT, P443

[2] ALKALINE-EARTH METAL-ION CATALYSIS OF ALCOHOLYSIS OF CROWN-ETHER ARYL ACETATES - EFFECT OF THE BASE SOLVENT SYSTEM [J].

CACCIAPAGLIA, R ;

MANDOLINI, L ;

REINHOUDT, DN ;

VERBOOM, W .

JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, 1992, 5 (10) :663-669

[3] THE BARIUM(II) COMPLEX OF P-TERT-BUTYLCALIX[4]ARENE-CROWN-5 - A NOVEL NUCLEOPHILIC CATALYST WITH TRANSACYLASE ACTIVITY [J].

CACCIAPAGLIA, R ;

CASNATI, A ;

MANDOLINI, L ;

UNGARO, R .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1992, 114 (27) :10956-10958

[4] CATALYSIS BY ALKALI AND ALKALINE-EARTH METAL-IONS IN NUCLEOPHILIC-ATTACK OF METHOXIDE ION ON CROWN ETHERS BEARING AN INTRA-ANNULAR ACETOXY GROUP [J].

CACCIAPAGLIA, R ;

LUCENTE, S ;

MANDOLINI, L ;

VANDOORN, AR ;

REINHOUDT, DN ;

VERBOOM, W .

TETRAHEDRON, 1989, 45 (16) :5293-5304

[5] DIFFERENTIAL METAL-ION STABILIZATION OF REACTANTS AND TRANSITION-STATES IN THE TRANSACYLATION OF CROWN-ETHER ARYL ACETATES [J].

CACCIAPAGLIA, R ;

VANDOORN, AR ;

MANDOLINI, L ;

REINHOUDT, DN ;

VERBOOM, W .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1992, 114 (07) :2611-2617

[6]

CACCIAPAGLIA R, 1994, P 2 C NAZL CHIM SUPR

[7] HOST-GUEST COMPLEXATION .21. CATALYSIS AND CHIRAL RECOGNITION THROUGH DESIGNED COMPLEXATION OF TRANSITION-STATES IN TRANSACYLATIONS OF AMINO ESTER SALTS [J].

CHAO, Y ;

WEISMAN, GR ;

SOGAH, GDY ;

CRAM, DJ .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1979, 101 (17) :4948-4958

[8] CATALYSIS AND CHIRAL RECOGNITION THROUGH DESIGNED COMPLEXATION OF TRANSITION-STATES IN TRANSACYLATIONS OF AMINO ESTER SALTS [J].

CHAO, Y ;

CRAM, DJ .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1976, 98 (04) :1015-1017

[9] ALKALI AND ALKALINE-EARTH METAL-ION CATALYSIS IN THE REACTION OF ARYL ACETATES WITH METHOXIDE ION - EFFECT OF A POLY(OXYETHYLENE) SIDE ARM [J].

ERCOLANI, G ;

MANDOLINI, L .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1990, 112 (01) :423-427

[10]

FERSHT A, 1985, ENZYME STRUCTURE MEC, pCH4

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