摘要:

AbstractStereospecific hydrohalogenation reactions of electron‐deficient alkynes, i.e., 2‐alkynoic acids, 2‐alkynoates, 2‐propynamides, 2‐propynenitrile, 1‐alkynyl phosphonates/phosphine oxides, 1‐alkynyl sulfoxides/triflones, and 1‐alkynyl iodonium salts with lithium or sodium halides to affordZ‐alkenyl derivatives and their applications in synthesis of important intermediates as well as natural produ

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160502

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY

摘要:

AbstractEPR study showed that the semi‐quinone radical anion of chloranil (TCQ) was formed in a charge‐transfer process between ground state chloranil as acceptor and each one of the following ground state donors, i.e.,N, N‐diethyl aniline (DEA), phenothiazine (PTZ), carbazole (CBZ), pyrene (PY), ferrocene (FRO), triphenylphosphine (TPP), triethylamine (TEA), anthracene (AN) andN, N‐diethyl‐3‐aminophenyl ester of palmitic acid (DPP). Our results indicate that there is a tunneling effect for the ground‐state charge‐transfer process between chlorani

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160503

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY

摘要:

AbstractThe aggregation properties of a series of deuteroporphyrin IX diesters in the THF‐Buffer (0.1 mol·L−lTris‐HCl) aquiorgano solvent have been studied by means of UV‐Vis and fluorescence spectrometers. Experimental data show that the dimerization of porphyrins is mainly determined by π‐π interaction in pure organic solution while further aggregation of porphyrins with long hydro‐carbon chains is more likely driven by hydrophobic‐lipophilic interaction in aqueous‐organic binary solution. The appearance of the aggregates induces a red shift in absorption spectra and fluorescence quenching in fluorescence spectra. The chain‐length effect and chain‐foldability effect h

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160504

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY

摘要:

AbstractThe densities of supercritical CO2‐tetrahydrofuran (cosolvent) binary mixture were measured at temperatures in range of 308.15 to 323.15 K and at pressure up to 16.5 MPa. The concentrations of tetrahydrofuran were from 0 to 0.57 mol/L. The partial molar volume of tetrahydrofuran was calculated based on the relationship between the density of the mixture and the concentration of the cosolvent. It is observed that the partial molar volume of the cosolvent is negative and the absolute value decreases with increasing pressure and the concentration of the cosolven

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160505

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY

摘要:

AbstractThe feasibility of photocatalytic decomposition of oil films floating on water using TiO2supported on hollow glass microbeads was studied. The results showed that 100% of ethylbenzene and 78% of dodecane can be photocatalytically removed after 8 h illumination with sunlight. The TiO2supported on the hollow glass microbeads was not easily detached from the beads. After 150 h illumination there was no significant loss of the photocatalytic activity of TiO2. Some intermediate products of photocatalytic decomposition of dodecane were detected.

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160506

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY

摘要:

AbstractThe coordination number of the gadolinium atom and bond distances in the crystal of monomeric porphyrinate, [Gd(TPP)acac·8H2O·3TCB] (TCB: 1,2,4‐trichlorobenzene, acac: anion of acetylacetone), were determined by EXAFS method. The Gd atom is eight‐coordinated to the four nitrogen atoms of a tetraphenylporphyrin ring, to the two oxygen atoms of one acetylacetonato anion and to two water molecules with Gd—N=0.232 nm, Gd—O

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160507

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY

摘要:

AbstractNine novel heteronuclear complexes of Ln(III)‐Cu(II) with salicylidene tetraethylene glycol diamine (SALTTA) have been synthesized and characterized. They have the general formulae [LnCu2(SALTTA)2(NO3)3](NO3)4·3H2O (Ln=La, Pr, Nd, Sm) and [LnCu3(SALTTA)3(NO3)5]‐(NO3)4·4H2O (Ln=Gd, Tb, Er, Yb, Y). The IR spectra show thatvC=Nin the Ln(III)‐Cu(II) heteronuclear complexes are splitted up into two peaks with a far distance. It has been confirmed that oxygen atoms in oxyethylene of the ligand are not all coordinated to the central metal ions by both IR and NMR

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160508

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY

摘要:

AbstractFour novel copper(II) complexes have been synthesized, namely Cu(hfac)2NITPhNO2(1), Cu(hfac)2NITPhCH3(2), Cu(pfpr)2NITPhNO2, (3) and Cu(pfpr)2NITPhCH3(4), where hfac=hexafluoro‐acetylacetonate, pfpr=pentafluoropropionate, NITR=2‐R‐4,4,5,5‐tetramethyl‐4,5‐dihydro‐1H‐imidazolyl‐1‐oxyl‐3‐oxide. (R=4‐nitrophenyl, 4‐methylphenyl). These complexes were characterized by elemental analyses, IR, electronic spectra and molar conductance. The temperature‐dependent magnetic susceptibility of complexes 1 and 3 have been studied in the 4–300 K range, giving the exchange integralJ=10.56 cm−lfor compl

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160509

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY

摘要:

AbstractThree new 27‐nor‐triterpenoid saponins named rubenorside A (l), rubenorside B (2) and rubenorside C (9) were isolated from the roots ofAdina rubella. Their structures were characterized as pyrocincholic acid 3β‐O‐α‐L‐rhamnopyranosyl(28→ 1)‐β‐D‐glucopyranosyl ester (1), pyrocincholic acid 3β‐O‐β‐D‐glucopyranosyl(1→2)‐β‐D‐fucopyranosyl(28→1)‐β‐D‐glucopyranosyl(1→6)‐β‐D‐glucopyranosyl ester (2) and pyrocincholic acid 3β‐O‐β‐D‐glucopyranosyl(1→2)‐β‐D‐glucopyranosyl (28→ 1)‐β‐D‐glucopyranosy

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160510

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY

摘要:

AbstractTwo novel cyclic polyamine derivatives bearing double aminoethyl groups have been synthesized. The synthetic intermediate,N‐p‐toluenesulfonyl‐aziridine, was prepared employing an improved proc

ISSN:1001-604X    

DOI:10.1002/cjoc.19980160511

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1998

数据来源: WILEY