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1.
Compounds of general formulatrans-ArNi(PR3)2OAr' (R = Et, cyclohexyl; Ar = 2-MeC6H4, 2-FC6H4; Ar' = 4-FC6H4, 4-NO2C6H4) were synthesized by the reaction of Ar'OK with cationic nickel complexes generated by treatment of ArNi(PR3)2Cl with TlBF4. Syntheses of 4-fluorophenoxide complexes, ArNi(PR3)2OC6H4F-4, additionally give some quantities oftrans-[ArNi(PR3)2OC6H4F-4][HOC6H4F-4] adducts. Exchange reactions MeC6H4Ni(PEt3)2OC6H4F-4 + XC6H4OH 2-MeC6H4Ni(PEt3)2OC6H4X + 4-FC6H4OH were studied in THF. The equilibrium is shifted to the right as the acidity of ArOH increases. A linear relationship between lgK
eq and pK
a of XC6H4OH in DMSO was found. A conclusion concerning the strong polarization of the Ni-O bond was made on the basis of an analysis of the chemical shifts of fluorine atoms in 2-MeC6H4Ni(PEt3)2OC6H4F-4.Translated fromIvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2266–2271, November, 1995. 相似文献
2.
The crucial factor of the reaction of 2,6-di-tert-butylphenol with alkali hydroxides is temperature, depending on which two types of potassium or sodium 2,6-di-tert-butylphenoxides are formed. These types exhibit different catalytic activity in the alkylation of 2,6-di-tert-butylphenol with methyl acrylate. More active forms of 2,6-But
2C6H3OK or 2,6-But
2C6H3ONa are synthesized at temperatures higher than 160 °C and are predominantly the monomers, which dimerize on cooling. The
data of 1H NMR, electronic, and IR spectra for the corresponding forms of 2,6-But
2C6H3OK and 2,6-But
2C6H3ONa isolated in the individual state are in agreement with cyclohexadienone structure. In DMSO or DMF, the dimeric forms of
2,6-di-tert-butylphenoxides react with methyl acrylate to form methyl 3-(4-hydroxy-3,5-di-tert-butylphenyl)propionate in 64–92% yield.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2138–2143, December, 2006. 相似文献
3.
本文以八种取代酚及相应的取代酚钾作为电子给体,以四氰基乙烯(TCNE)作为电子受体,在乙腈溶液中用紫外可见分光光度法测定了取代酚及相应的取代酚钾与TCNE作用的电荷转移络合物的光谱,以其CT光谱用比较法计算了取代酚及相应的取代酚钾的电离势。结果表明,除4-氰基苯酚外,其余取代酚及取代酚钾均可与TCNE形成电荷转移络合物,取代酚钾比相应的取代酚有更好的给电子能力,取代酚的电子转移能与Hammet取代基常数有较好的线性相关关系。 相似文献
4.
Virgil Percec Shigeru Okita 《Journal of polymer science. Part A, Polymer chemistry》1993,31(4):923-932
The nucleophilic substitution reactions of 1,4-dichlorobenzene chromium tricarbonyl ( 1 ) with the phenoxide anion were investigated. The substitution of the first chlorine was very fast and gave the mono-substituted product in high yield. The substitution of the second chlorine group was significantly retarded by the presence of the phenoxy group incorporated during the first reaction and also due to the competing decomplexation reaction. The application of 1,4-dichlorobenzene chromium tricarbonyl ( 1 ) to the synthesis of new monomers was demonstrated by the preparation of 2,2′-bis[4-(4-chlorophenoxy)phenyl]propane ( 9 ). 2,2′-Bis[4-(4-chlorophenoxyl)phenyl]propane ( 9 ) was synthesized by a nucleophilic substitution reaction of 4,4′-isopropylidenediphenolate with 1,4-dichlorobenzene chromium tricarbonyl ( 1 ) followed by decomplexation with I2. 2,2′-Bis[4-(4-chlorophenoxy)-phenyl]propane ( 9 ) was also synthesized via a three-step reaction starting from the nucleophilic substitution reaction of 4,4′-isopropylidenediphenol ( 7a ) with 1-chloro-4-nitrobenzene ( 10 ). 2,2′-Bis[4-(4-chlorophenoxy)phenyl]propane ( 9 ) was polymerized by a Ni(0)-catalyzed reaction to yield amorphous aromatic polyethers with number-average molecular weights of up to 11,200 g/mol. © 1993 John Wiley & Sons, Inc. 相似文献
5.
Different tributyltin phenoxides react at room temperature with ethyl propiolate in benzene, in the presence of tin(IV) chloride, triethylamine and their mixture to give the derivatives of 3‐phenoxyacrylic acid ethyl ester. Exceptionally, 3‐(2‐hydroxyphenyl)acrylic acid ethyl ester and 3‐(2‐hydroxy‐5‐methylphenyl)acrylic acid ethyl ester have been obtained from the reaction of tributylphenoxytin and tributyl(p‐tolyloxy)tin, respectively catalysed by SnCl4, and they have been easily hydrolysed to coumarin and 6‐methylcoumarin. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
6.
The kinetics of catalytic alkylation of 2,6-di-tert-butylphenol (ArOH) with methyl acrylate (MA) in the presence of potassium 2,6-di-tert-butylphenoxide (ArOK) depends on the method for the preparation of ArOK. The reaction of ArOH with KOH at temperatures >
180 °C affords monomeric ArOK, whose properties differ from those in the case of potassium 2,6-di-tert-butylphenoxide synthesized by the earlier methods. The regularities of ArOH alkylation depend on the ArOK concentration,
the ArOH: MA ratio, and the effect of microadditives of polar solvents.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1971–1974, October, 2007. 相似文献
7.
The effect of increase of polarity of the solvent binary mixture methanol-benzene and acetonitrile-chloroform on the selectivity and the rate of metalloene reaction of different allyltin compounds with 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD), diethyl azodicarboxylate (DEAD) and singlet oxygen was studied. The more polar solvent favored the production of the M-ene product. Analogous comparative studies were carried out in Et2O and 4 mol dm−3 solutions of LiClO4 in diethyl ether. All studied reactions were strongly catalysed by LiClO4. Physicochemical studies were carried out in purpose to explain the catalytic effect of LiClO4 on the aforementioned reactions. In case of singlet oxygen and diethyl azodicarboxylate it was presumably a result of facilitation of the formation of the polar intermediate by the ionic medium. Whereas, in case of PTAD the mentioned previously effect could be associated with lowering its LUMO by association with lithium. The analogous catalytic effect of LiClO4 was also observed for reactions of organotin phenoxides with DEAD and bis(trichloroethyl) azodicarboxylate leading to corresponding ring-aminated phenols in excellent yield, and with diethyl acetylenedicarboxylate giving a mixture of corresponding vinyl ethers and ring ethenylated phenols. Organotin phenoxides were distinctly more active than the corresponding phenols. 相似文献
8.
9.
Studies on the catalysis of the reaction of organotin phenoxides with diethyl acetylenedicarboxylate
Different organotin phenoxides react at room temperature with diethyl acetylenedicarboxylate in diethyl ether, in the presence of lithium perchlorate to give a mixture of corresponding phenyl vinyl ethers and ring ethenylated phenols. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
10.
Zuniga MF Deacon GB Ruhlandt-Senge K 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(7):1921-1928
The preparation of heterobimetallic complexes consisting of alkali and heavy alkaline earth metals remains a challenge due to limited available synthetic strategies. Here we present a new class of group 1, Ba compounds of the type [M(n){Ba(Odpp)(2+n)}] (M=Na(n=1) (1), K(n=1) (2), Cs(n=1) (3), Li(n=2) (4); HOdpp=2,6-diphenylphenol) and the Lewis base adducts [Li(2)(thf)(2){Ba(Odpp)(4)}]PhMe (5) and [K{Ba(Odpp)(3)(diglyme)}] (6) (diglyme=[bis(2-methoxy)ethyl ether]) as the first representatives of heterobimetallic group 1, Ba species of low nuclearity. The compounds display a significant degree of metal-arene interaction, believed to be a key factor in stabilizing these highly reactive species. Obtained by solid-state direct metalation, the target compounds are available without further work-up. 相似文献