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1.
1INTRODUCTION Atom transfer radical addition is an efficient me-thod for carbon-carbon bond formation in organic synthesis[1,2].In some of these reactions,a transi-tion-metal catalyst acts as a carrier of the halogen atom in a reversible redox process.The transition-metal-catalyzed has been successfully used to con-trol radical polymerization[3].In the process,the transition-metal species initially abstracts halogen atom X from organic halide to form oxidized species and carbon-centered r…  相似文献   

2.
1 INTRODUCTION The research on organic polyamines is currently of great interest because of their potential applica- tions as useful organic ligands, in which the amine nitrogen atoms have strong coordination ability to the transition metal ions and recognition function[1~4]. Their transition metal complexes play an excellent role in catalysis and mimic studies on dismutase and chlorophyll[5~7]. Therefore much attention has been focused on their syntheses and applications[8~11]. Our group…  相似文献   

3.
1 INTRODUCTION 2-Aminochromene is an important class of com- pounds found as the main compounds of many naturally occurring products employed as cos- metics and pigments[1] and utilized as potential biodegradable agrochemicals[2~4]. The utility of fluoride salts as potential base in variety of syn- thetic reactions has been recognized in recent years[5, 6]. However, low solubility of fluoride salts in ordinary solvents limits their wide applications in organic syntheses. On the other ha…  相似文献   

4.
1 INTRODUCTION Palladium compounds have attracted much attention as a consequence of their application in homogeneous and heterogeneous catalyses[1]. For instance, palladium compounds are the most active catalysts for the carbonylation, such as palladium-catalyzed carbonylation of nitroarenes, aryl halides, alkyne and so on[2~4]. Some dramatic results in the homogeneous catalysis of the reactions of organic compounds, particularly the successful commercial exploitation of the Wacker on…  相似文献   

5.
Samarium diiodide and organosamarium compounds have been widely employed as useful reagents in organic synthesis1. However, relatively few reports on the direct use of samarium metal in organic synthesis have been reported2, because the surface of samarium metal is inactive3. In order to improve the activity of samarium, some additives, such as HgCl24, NH4Cl (aq.)5, or TMSCl6 were added.The reduction of azides to the corresponding amines is an important reaction in organic synthesis7-16. A…  相似文献   

6.
Compared to the extensive use of samarium diiodide in organic synthesis', little reportsappeared on the application of samarium metal in organic synthesis. As early as 1971Evans and co-workers had prepared phenylsamarium iodide from iodo-benzene andsamarium metal'. But they found that samarium is not so active as ytterbium. In 1986Fukuzawa also prepared the organosamarium intermediate similar to Grignard reagent'.It was Curran who firstly proved and named the samarium Grignard reaction in 19…  相似文献   

7.
The chemistry of samarium (II) iodide (SmI2) is of current interest in organic synthesis. SmI2 has been developed as a powerful, versatile and ether-soluble single-electron reductant and many examples have been reported of its use in the reduction of various functional groups1. Though SmI2 is a useful reagent, storage is difficult because it is very sensitive to air oxidation. On the other hand, metallic samarium is stable in air and has strong reducing power (Sm3+/Sm=-2.41 V). These pr…  相似文献   

8.
李明  郭维斯  文丽荣  曲波 《结构化学》2006,25(1):108-112
1INTRODUCTION Pyrazolo[1,5-a]pyrimidine derivatives have shown various biological activities in the terms of antibac-terial,antischistosomal and xanthine oxidase inhibi-tors[1~5].The enaminones are highly reactive inter-mediates and have been extensively used as build-ing blocks in organic synthesis especially in the he-terocyclic compounds[6~8].In addition,a great deal of interest has been focused on the synthesis of py-razolo[1,5-a]pyrimidine through versatile enamino-nes because of thei…  相似文献   

9.
1 INTRODUCTION Palladium (Ⅱ) coordination and organometallic compounds usually show square planar environments at the metal center[1], and have experienced an im- portant development in the past years due to their acting as intermediates in different types of catalytic reactions and numerous applications in organic synthesis[2]. Although palladium plays an increase- ingly recognized role as a biometal[3], little is known about the structure and function of palladium compounds in living …  相似文献   

10.
1 INTRODUCTION The researches on organic polyamines are currently of great interest because of their potential applications as useful organic ligands, in which the amine nitrogen atoms have strong coordination ability to the transition metal ions. Their transition metal complexes play an excellent role in catalysis and the mimic studies on superoxide dismutase and chlorophyll[1~6]. N,N,N?,N?-Tetrakis(3-ami- nopropyl) ethylenediamine has been extensively stu- died[7~9], but few new ineq…  相似文献   

11.
1 INTRODUCTION It was reported that the pyrazolopyrimidinone derivatives play a very important role in the bio- chemistry of living cell. Many potential drugs[1~3] and agrochemicals[4, 5] have been modeled on the compound, and the study on derivatives …  相似文献   

12.
1INTRODUCTIONTheSchiffbasesderivedfromb-diketonesandaliphaticamineshavebeenshowntoexistastheketo-amines.However,ifsubstituentseitherattheketooraminogrouparearomatic,itmaybeexpectedtheenoliminewillbethefavoredtautomericform[1].Recently,someSchiffbasesderivedfromTTA(4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione)andPMBPhavebeenstudiedbyWang[2]andYu[3]etal.Inordertostudytherelationshipbetweenthestructuresandperformancesofthesecompounds,thetitlecom-poundwillbereportedherein.2EXPERIMENT…  相似文献   

13.
1 INTRODUCTION Phosphorus-containing vinyl compounds havebeen widely studied due to their versatile physiolo-gical activities and applications in transition metalchemistry, asymmetric catalysis and photorearrange-ment[1~4]. In our previous papers, we have reportedthe syntheses of 2,2,4,5-tetrasubstituted-1,3-dithio-les[5] and 2,5-bis(morpholino)-3,4-bis-(p-chloro-phe-nyl)thiophenes[6] by the reactions of α-thioaroyl-thiofor-mamide with trimethyl phosphite at room tempera-ture and in refl…  相似文献   

14.
The title compound(E)-2-(4-tert-butyl-5-(4-methoxybenzyl)thiazol-2-ylimino)me-thylphenol was synthesized by the reaction of 5-(4-methoxybenzyl)-4-tert-butylthiazol-2-amine with salicylaldehyde=and its crystal structure was determined by single-crystal X-ray diffraction.The crystal belongs to the monoclinic system=space group P21/c with a=5.9362(8)=b=11.5070(15)=c=29.460(4)=β=97.326(3)°=V=1995.9(5)3=Z=4=F(000)=808=C22H24N2O2S=Mr=380.49=Dc=1.266 g/cm3=S=1.031=μ=0.181 mm--1=the final R=0.0474 and wR=0.1441 for 4327 observed reflections(I > 2σ(I)).Intramolecular O-H…N hydrogen bond is observed in the crystal.The preliminary bioassay showed that the title compound exhibits 95% inhibition rate against Rhizoctonia solani at the test concentration of 500 mg/L.  相似文献   

15.
The title compound (C20H21N3O4, Mr = 367.40) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction. The crystal is of orthorhombic, space group P212121 with a = 7.5143(15), b = 13.901(3), c = 18.545(4) , V = 1937.1(7) 3, Z = 4, Dc = 1.260 g/cm3, μ = 0.089 mm-1, F(000) = 776, the final R = 0.0616 and wR = 0.0912. X-ray diffraction reveals that the molecule adopts an E configuration about the central C=N double bond. The intermolecular O–H…O hydrogen bond stabilizes the crystal structure by causing the formation of a supramolecular architecture.  相似文献   

16.
宋新建  王胜  汪焱钢 《结构化学》2006,25(4):402-406
1 INTRODUCTION 1,3,4-Thiadiazole derivatives represent an interes- ting class of compounds possessing broad spectrum biological activities[1~4]. Aroyl ureas are known to exhibit diverse biological effects, such as insecticidal, fungicidal, herbicidal and plant growth regulating activities[5~8]. Therefore, it is worthwhile to investi- gate the compounds incorporating both 1,3,4-thiadia- zole nucleus and aroyl urea group. In the previous paper[9], a series of aroyl ureas containing 1,3,4-t…  相似文献   

17.
<正>The title compound methyl (7,7-dimemyl-2-amino-4-(4-chlorophenyl)-5-oxo-5,6,7,8-tetrahydro-4H-benzo-[b]-pyran-3-yl) carboxylate (C19H20ClNO4, Mr = 361.81) was synthesized and crystallized. The crystal belongs to triclinic, space group P 1 with a = 8.519(2), b = 10.346(2), c = 11.481(3) A, α = 108.16(1), β = 107.78(2), γ= 91.83(2)°, Z = 2, V = 906.5(3) A3, Dc = 1.326 g/cm3, μ(MoKα) = 0.234 mm-1, F(000) = 380, R = 0.0467 and wR = 0.1270 for 3142 observed reflections (I > 2σ(I)). X-ray analysis reveals that the C(7), C(8), C(9), O(1), C(10) and C(11) atoms form a six-membered ring which adopts a boat conformation. In the ring, the distances of C(8)-C(9) and C(10)-C(11) are 1.332(3) and 1.357(3) A, respectively, which indicates that they are C=C double bonds. Another six-membered ring (C(8)-C(9)-C(15)-C(14)-C(13)-C(12)) adopts the half-chair confonnation. In addition, there are intermolecular hydrogen bonds in the crystal structure.  相似文献   

18.
The title compound (2E,3E)-N1,N2-bis(2,3,4-trimethoxy-6-methylbenzylidene)- ethane-l,2-diamine (C24H32N2O6, Mr = 444.52) was synthesized and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The crystal belongs to triclinic, space group P2/c, with a = 8.5480(10), b = 9.3710(12), c = 15.280(2)A, β = 90.780(2)°, V= 1223.9(3)A3, Z = 2, Dc= 1.206 g/cm3, 2 = 0.71073A,μ(MoKa) = 0.087 mm^-1, F(000) = 476, the final R = 0.0680 and wR = 0.1450 for 2144 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals that the molecule adopts an E configuration about the central C=N functional bond. The phenyl rings of two 2,3,4-trimethoxy-6-methylbenzaldehyde groups are symmetrically parallel. The molecules are linked through C-H…O hydrogen bonding interactions. The title compound possesses moderate antibacterial activity.  相似文献   

19.
1 INTRODUCTION Aminopeptidase N (APN), a member of mem- brane-bound zinc-dependent exopeptidase, is known to be high expression on the brush border membran- es of the small intestine and renal proximal tubules[1]. The over-expression of APN has been involved in several pathological conditions including cancer[2], leukemia, diabetic nephropathy[3], rheumatoid arth- ritis[4], angiogenesis[5] and central nervous system di- seases, such as Alzheimer’s disease[6]. This has led to the sear…  相似文献   

20.
1 INTRODUCTION Low-valent titanium reagents have exceedinglyhigh abilities to promote reductive coupling of car-bonyl compounds and they are attracting increasinginterest in organic synthesis[1]. Many other func-tional groups can also be coupled[2~8]. Recently, wehave reported some intermolecular reductive cou-pling reactions[9~12] and some new intramolecular re-ductive coupling reactions[13~16] induced by low-va-lent titanium reagents. The spiro[4.4]nonane skeleton has been found inmany…  相似文献   

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