共查询到20条相似文献,搜索用时 15 毫秒
1.
《中国化学》1993,(2)
Polyfluoroalkyl iodides reacted with olefins in aqueous DMF solution of sodiumdisulfite under mild conditions to give the corresponding 1:1 adducts in good yields,providinga convenient polyfluoroalkylation method.This indicated that R_F radicals were formed inthe reaction of polyfluoroalkyl iodides and sodium disulfite.A SET mechanism is proposedfor the sulfinatodehalogenation reaction of sodium disulfite. 相似文献
2.
WU Fan-Hong HUANG Bing-Nan HUANG Wei-YuanShanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai China 《中国化学》1996,14(4):373-376
Without oxidant, sodium bisulfite reacted with polyfluoroalkyl iodides and bromides in aqueous DMF solution to give the corresponding sulfinates in good yields. 相似文献
3.
HUANG Wei-Yuan WU Fan-Hong HUANG Bing-NanShanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai China 《中国化学》1994,12(6):549-551
Polyfluoroalkyl iodides, such as Cl(CF2)nI(n=4, 6, 8, 1b-1d) and F(CF2)nI (n=6, 8,1e-1f) reacted with sodium sulfite in neutral aqueous DMF solution to give the corresponding sulfinates Cl(CF2)nSO2Na (n=4, 6, 8, 2b-2d) and F(CF2)nSO2Na (n=6, 8, 2e-2f) in moderate yields. I(CF2)2O(CF2)2SO2F ( la ) reacted under the same condition to give 3-oxa-octafluoropentane-1,5-disulfinates (2a). 相似文献
4.
Reaction of tetrakis(p-allyloxyphenyl)porphyrin and perfluoroalkanesulfonyl bromides givestetrakis(p-polyfluoroalkoxylphenyl)substituted porphyrins.The yields are over 90%.The synthesis ofthe metal ion complexes of these F-containing porphyrins is also reported.Preliminary results on thestudy of the catalytic activity of the manganese(Ⅲ)complexes of various fluorinated porphyrins onoxidation of cyclohexene indicate that the introduction of R_F group into porphyrin contributes to thestability of the catalysts. 相似文献
5.
Russian Chemical Bulletin - 相似文献
6.
HU Qiao-Sheng HU Chang-Ming HUANG Wei-YuanShanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai China 《中国化学》1997,15(5):472-474
Sodium dithionite initiated sulfinatodehalogenation of BrCF2CF2R is studied. 相似文献
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Chun Li Wu Yan Zhang Ji Yu Guo* Xiao Tian Liang Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 《中国化学快报》2002,13(1)
Agarofurans have been found to be active on the nervous system in our institute. 4-Butyl-a-agarofuran 1 is a promising drug candidate. In order to explore the pharmacokinetics of 1, the metabolism of 1 in vitro was studied with liver microsomes from rats. Five metabolites were isolated and structures were identified as compounds 2-6. But the absolute configuration of 2,4,5 and the position of carbonyl in 3 could not be unambiguously determined. Further determination was limited by the smal… 相似文献
9.
Agarotlirans were found to be bioactive on nervous system. 3,4-dihydroxy dihydroagarofuran (l)' is only one of this group of natural products, which has substituent on C3 position.We synthesized this compound by the reported nletllod' and tbund it to possess somespecific bioactivity on nervous system. In order to search for more active compounds, wedecided to modify agarofurans on C-3 position beginning with the synthesis of 14-nor-3oxodihydroagarofuran (2).In the initial stage of the synthes… 相似文献
10.
《中国化学快报》2000,(5)
Agarowoodoilwasfoundtobebioactiveinpharmacologicalscreeningforthenervoussysteminourinstitute.AgarofuransareonesmicturaltypeoftheimportantconstituentSofagarowoodoil.Q-Agarofuran(lh),oneofthemanyconstitUentsoftheoil,issuspectedofbeinganimportantcontributortothebioactivity.AlthoughseveralsynthesisofQ-agarofuran(fo)havebeendescribed'-',theyarenotsuitableforthesynthesisofitsanalogs.Thebioactivitiespromptedustodevelopanewroutetoa-agarofuran(fo)anditsanalogs.EarliersynthesisofQ-agarofuran(lb),with… 相似文献
11.
《中国化学快报》1997,(10)
Prev~n1,acembranopditerpenoid,wasfirstisolatedfromsoftcoral(VeretilIumcoporium)inl99(),anditSmCtUrwasehablishedas(+)-(lE,3E,7E,llE)-cembra-l,3,7,ll-tetraen6-olaeetate[l].SofarasweknOW,thetotalSynthsisof1hasnobeenrePOrtedyet.Herein.wewishtodescribethetotalpeisoftheprecursor(9),theSynthhcroutewasouthnedbelowfa)HBr.80%;b).CH3C02Na.CH3CO2H,75%,c).Se02-I-Bu00H,70%,d).CCl',PPh3,83%,e).NaSQPh.DMF.9O%,O.K=CO3.MeOH,95%,g).DHP,Ts0H.8O%,h),TBAB,5O%NaOH,aq.,5%;i).Li-Effez.M,70%;j… 相似文献
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《中国化学》1993,(5)
In previous communications we have reported that arteannuic acid(1,Scheme1)is a common precursor of the biosynthesis of both arteannuin(2)and arteannuinB(3)by the leaf homogenate of the plant Qinghao(Artemesia annua L.).It seemsthat most likely the oxidation of allylic tertiary carbon atom,C-6,may occur early inthe biosynthetic path of 2 and 3 from 1.Natural 6-epi-deoxyarteannuin B(4)isolated 相似文献
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《中国化学快报》1997,(1)
TheindoidsxillosoIandt4llosolsidewereisolatalinl985frOmPatriDiavi11osa,atradihonalChineseherbmedicineusedfortreatofconunoncoldandparohhsmUInPS.PhannacologicalstUdieshaveestablishedthattheyshowanti-inflannnatOryachvihes.BasedonspeCtraldata,chenucaltransformationsandanalysisOfCDbehaviorofthelactonering,x-illosolsideandvillosolhavebeengivensmictUresland2respeCtively.[']Itisinterestingthatthesenot-eltridoidshat,ereversedstereocheAnsto'atC5andC9junCtUreSwith5Q,9Qinsteadoftheusuall}'found5… 相似文献
16.
Studies on Catalytic Conversion of Ethylene 总被引:2,自引:0,他引:2
Fuyu Liu Chunyi Li Xue Ding Xinghua You 《天然气化学杂志》2007,16(3):301-307
FCC dry gas contains a large amount of ethylene.It is used by most of the refineries in China as fuel or simply burned in atmosphere.Few refineries make good use of the dry gas,so the precious ethylene resource in the dry gas is wasted.In this article,the possibility of catalytic conversion of ethylene to C_3,C_4,and some high molecular weight hydrocarbons in a fixed bed micro-reactor using LTB-1 catalyst,with pure ethylene as feedstock was studied.Effects of reaction temperature,reaction pressure,and feedstock flow rate,on the conversion of ethylene and the distribution of products were investigated to determine the proper reaction parameters to be used in practice.Good results indicate that this study may provide a new way of using the ethylene resource in the FCC dry gas. 相似文献
17.
Through kinetic method, the reaction mechanism and the rate equations of chlorination of polyethylene are suggested in this paper. The rate of chlorination is second order with respect to the concentration of methylene remained and chlorine, respectively. Apparent changes in crystallinity during chlorination processes were determinated by differential scanning calorimetry(DSC). The mathematical model relating crystallinety with kinetic parameters and function of sequence length distribution are derived. 相似文献
18.
An efficient catalytic system consisting of vanadyl sulfate/sodium nitrite was disclosed previously for the oxidation of benzylic alcohols into aldehydes with molecular oxygen.However,the roles of catalyst components were not investigated.In this paper,we examined catalytic oxidation of benzyl alcohol as a model reaction,especially by infrared spectroscopy.The role of each component is discussed including nitrite,vanadyl,sulphate,and water.Sodium nitrite could be converted into nitrate and nitric acid.The vanadium(IV)could be smoothly oxidized into vanadium(V)under mild and acidic conditions without any organic ligands.The transformation of sulfate and bisulfate,the cessation of an induction period,and the oxidation of benzyl alcohol were closely interrelated.The multiple roles of water are discussed,including reduction of the induction period,participation in redox cycles of nitric compounds,deactivation of vanadium,and as a byproduct of oxidation.This study contributes to further development of aerobic oxidation using vanadium based catalysts. 相似文献
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《中国化学快报》1997,(8)
Trifloorovinylcompoundswereusefulmonomersusedwidelyinthepolymerfield.Synthesisofsuchcompoundsattractsmuchattention.Functionalizedtrifluorovinylcompoundshaveuniquepropertiesasmonomersinpolymerizationandcanbeexpectedtoundergoselectivereactionsatthetrifluorovinyloratthefunctionalgroupsite.lHowever,fewpapershaveappearedonthepreparationofsuchcompounds.2'3InthecontinuingstudyonthesulfinatodehalogenationofBrCF2CFClR,aseriesoftrifluoroalkylcompoundswereobtained.Hereinwereporttheresults.Treatmentof… 相似文献