Oxidation of theexo- andendo-phenylcyclohexadienyl iron complexes Fe(η5-6-PhC6H6) (η5- C5H5)

The roe of oxidatively induced homolyhc scission a the C(sp³)-H bonds in the iron phenykychhexadienyl complexes Fe(⁵-6-PhC₆H₆)(⁵-C₅H₅) (1) depends on the spatial orientation of the Ph substitutent. In the case of the (1 _endo ⁺) radical cation this process, resulting in the cationic biphenyl complex (Fe(⁶ -C₆H₅C₆H₅)(⁵-C₅H₅)]⁺ (2 ⁺), is fast and proceeds for several minutes. In the case of the more stable radical cation (1 _exo ⁺) the formation of 2⁺ is slow and takes tens minutes to complete.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1698–1700, July, 1996.     

Synthesis and structure of η6-(biphenyl)-η5- (cyclopentadienyl)iron(II) hexaflourophosphates

A series of η⁶-(biphenyl)-η⁵-(cyclopentadienyl)iron(II) hexafluorophosphates have been prepared. Demethylation occured during the synthesis of the 2′-OMe derivatives to yield the correspoding 2′-OH product. The mechanism of this process is discussed. In all cases the complexation involved the unsubstituted phenyl ring. From ¹³C NMR data, values of Hammett resonance parameters σ_R, were calculated which show that the [CpfeC₆H₅]⁺ group behaves as an electron-withdrawing substituent comparable in strength to the cyano group. Approximate values of the biphenyl interplanar angle (θ) were obtained. θ appeared to be significantly lower when electron-releasing substituents were present. ⁵⁷ Fe Mössbauer data support the strong electron acceptor properties of the [CpFe⁺C₆H₅] moiety. In particular the quadrupole splitting (QS) shows a marked increase for the 4-OMe derivative relative to the unsubstituted comples. This is in direct contrast to the aryl ferrocenes. Here, the ferrocenyl and OMe substituents are electronically and so there is no (QS) enhancement.     

5(6)-羧基荧光素标记2′-脱氧尿苷的合成

以5-碘-2'-脱氧尿嘧啶为起始原料, 5(6)-羧基荧光素为荧光标记物, 经6步反应合成了5(6)-羧基荧光素标记的2′-脱氧尿苷, 并利用高效液相色谱(HPLC), ¹H NMR和¹³C NMR对目标化合物的纯度和结构进行了表征.     

Why are SiX5(-) and GeX5(-) (X = F, Cl) stable but not CF5(-) and CCl5(-)?

The possible existence of the CF(5)(-), CCl(5)(-), SiF(5)(-), SiCl(5)(-), GeF(5)(-), and GeCl(5)(-) anions has been investigated using ab initio methods. The species containing Si and Ge as central atoms were found to adopt the D(3h)-symmetry trigonal bipyramidal equilibrium structures whose thermodynamic stabilities were confirmed by examining the most probable fragmentation channels. The ab initio re-examination of the electronic stabilities of the SiF(5)(-), SiCl(5)(-), GeF(5)(-), and GeCl(5)(-) anions [using the OVGF(full) method with the 6-311+G(3df) basis set] led to the very large vertical electron detachment (VDE) energies of 9.316 eV (SiF(5)(-)) and 9.742 eV (GeF(5)(-)), whereas smaller VDEs of 6.196 and 6.452 eV were predicted for the SiCl(5)(-) and GeCl(5)(-) species, respectively. By contrast, the high-symmetry and structurally compact anionic CF(5)(-) and CCl(5)(-) systems cannot exist due to the strongly repulsive potential predicted for the X(-) (F(-) or Cl(-)) approaching the CX(4) (CF(4) or CCl(4)). The formation of weakly bound CX(4)···X(-) (CF(4)···F(-) and CCl(4)···Cl(-)) anionic complexes (consisting of pseudotetrahedral neutral CX(4) with the weakly tethered X(-)) might be expected at low temperatures (approaching 0 K), whereas neither CX(5)(-) (CF(5)(-), CCl(5)(-)) systems nor CX(4)···X(-) (CF(4)···F(-) and CCl(4)···Cl(-)) complexes can exist in the elevated temperatures (above 0K) due to their susceptibility to the fragmentation (leading to the X(-) loss).     

微波辐射快速合成2-(2′-羟苯基)-5(6)取代苯并咪唑衍生物

苯并咪唑衍生物具有一定的抗病毒能力[1 ] ,一些苯并咪唑衍生物已用作农用抗植物病毒剂[2 ] 。一锅煮合成反应时间较长 ,产率中等[3,4] 。本文用取代邻苯二胺和水杨酸为原料 ,吡啶为溶剂 ,ＰＯＣｌ3为催化剂 ,微波辐射法合成了标题化合物。合成路线如下 :1　实验部分1 1　仪器ＷＣ 1型熔点测定仪 (温度计未校正 ) ;日本岛津ＩＲ 435红外光谱仪 (ＫＢｒ压片 ) ;ＴＥＯＬ ＦＸ90Ｑ核磁共振仪 ,ＤＭＳＯ ｄ6 为溶剂 ;日本柳公Ｃ·Ｈ·Ｎ元素分析仪ＭＴ 3;苏州三星电子有限公司产新天地Ｍ9Ｋ88型微波炉 ,输出功率 85 0Ｗ ,2 4 5 0Ｈｚ。1 2　…     

微波辐射快速合成2-(2＇-羟苯基)-5(6)取代苯并咪唑衍生物

苯并咪唑衍生物具有一定的抗病毒能力[1],一些苯并咪唑衍生物已用作农用抗植物病毒剂[2].一锅煮合成反应时间较长,产率中等[3,4].本文用取代邻苯二胺和水杨酸为原料,吡啶为溶剂,POCl3为催化剂,微波辐射法合成了标题化合物.     

2-(6-甲基-2-苯并噻唑偶氮)-5-二乙胺基酚吸光光度法测定微量Co(Ⅱ)

噻唑偶氮类试剂吸光光度法测定钴报道灵敏度均小于 1 .0 5× 1 0 5L· mol- 1 ·cm- 1 [1～ 4] 。本文报道用 2 - ( 6-甲基 - 2 -苯并噻唑偶氮 ) - 5-二乙胺基酚( MBTAE)测定微量钴 ,摩尔吸光系数为 1 .1 5×1 0 5L· mol- 1 · cm- 1 ,是目前同类试剂二元体系测钴灵敏度最高的一种方法。试剂与 Co2 反应迅速 ,配合物可稳定 1 6h。试剂最大吸收波长 λmax为51 5nm,配合物的最大吸收波长λmax为 61 0 nm,对比度 95nm,在 p H5.0的 HOAc- Na OAc介质中 Co∶MBTAE=1∶ 2 ,Co2 浓度在 0～ 2 5μg/ 2 5ml范围内服从比耳定律。方法应用…     

4-(5-硝基-6-羟基-2-苯并(噁)唑基)苯甲酸甲酯的合成

研究了以关键中间体4-氨基-6-硝基间苯二酚盐酸盐(ANR·HCl)和对苯二甲酸单甲酯(MTA)为原料,分别经酰氯化、缩合、环合分步或原位合成AB型新单体前体-4-(5-硝基-6-羟基-2-苯并唑基)苯甲酸甲酯(MNB)的技术. 反应优化条件为:在甲基异丁基酮溶剂中,n(ANR·HCl)∶ n(MTA)=1.00∶ 1.03,115 ℃缩合反应2.5 h,m(ANR·HCl)∶ m(PPA)=1.00∶ 3.25的多聚磷酸(PPA),120 ℃环合8.5 h,MNB收率75.68%(以ANR·HCl计),HPLC测定ω(MNB)=96.32%. 产物结构经1H NMR和IR测试技术得以确证.     

6-(3-氨基苯基)-4, 5-二氢哒嗪-3(2H)-酮的合成

以苯、丁二酸酐为原料,经傅克酰基化,硝化,与水合肼反应三步反应合成6-(3-氨基苯基)-4,5-二氢哒嗪-3(2H)-酮(1),总收率为58.3%。由3-(3-硝基苯甲酰基)丙酸(3)合成化合物1的过程中,在雷尼镍(Raney Ni)的催化下与水合肼反应,一步完成了苯环上硝基的还原和成环。重点考察了该步反应的物料配比、反应时间对产率的影响。结果表明,水合肼与化合物3的摩尔比11.7∶1,回流反应4 h,产率为82.7%。     

5(6)-氨基-1-(4-氨基苯基)-1,3,3-三甲基茚满合成及工艺优化

以5(6)-硝基-1-(4-硝基苯基)-1,3,3-三甲基茚满为原料,Pd/C为催化剂,用氢气还原合成5(6)-氨基-1-(4-氨基苯基)-1,3,3-三甲基茚满。红外、核磁表征了产物结构;考察了反应温度、反应时间、充入氢气压力及催化剂用量四个因素,设计正交试验对还原工艺条件进行优化分析。结果表明,对粗产率的影响显著程度依次为充入H2压力、反应时间、反应温度和催化剂用量,获得了优化工艺条件,即反应温度70℃、反应时间为2 h、充入H2压力为1.5 MPa,催化剂用量为5(6)-硝基-1-(4-硝基苯基)-1,3,3-三甲基茚满的10%。     

5(6)-羧基荧光素标记2''-脱氧尿苷的合成

以5-碘-2'-脱氧尿嘧啶为起始原料,5(6)-羧基荧光素为荧光标记物,经6步反应合成了5(6)-羧基荧光素标记的2'-脱氧尿苷,并利用高效液相色谱(HPLC),1H NMR和13C NMR对目标化合物的纯度和结构进行了表征.     

(5R,6R)-6-苯基-5-(苯磺酰基乙酰基)二环[2.2.1]-2-庚烯的合成及结构表征

报道了一种制备4-苯基-1-苯磺酰基-3-丁烯-2-酮的新合成方法. 4-苯基-3-丁烯-2-酮与溴化试剂Ph₃P^＋CH₂CH₂- COOHBr 作用, 得到1-溴-4-苯基-3-丁烯-2-酮, 不经分离直接与苯亚磺酸钠发生亲核取代反应, 得到4-苯基-1-苯磺酰基-3-丁烯-2-酮. 将此反应产物作为亲双烯体与环戊二烯在手性钛金属催化剂催化下进行不对称Diels-Alder反应, 得到了＞99% ee 的环加成产物(5R,6R)-6-苯基-5-(苯磺酰基乙酰基)二环[2.2.1]-2-庚烯. 用X衍射法对产物的晶体结构进行了测定, 讨论了反应机理, 通过元素分析, NMR, MS对产物的结构进行了表征.     

(5S)-5-烷氧基-3,4-二卤-2(5H)-呋喃酮与氨基酸的串联反应

在氢氧化钾作用下,直接以不同种类氨基酸为亲核试剂,与手性(5S)-5-烷氧基-3,4-二卤-2(5H)-呋喃酮在室温下进行串联的不对称迈克尔加成-消除反应,合成了15个新的光学活性2(5H)-呋喃酮衍生物.通过旋光度,UV-Vis,IR,1H NMR,13C NMR,MS,元素分析和X射线单晶衍射等表征方法,确定了目标化合物的化学结构和绝对构型.     

SYNTHESIS AND CRYSTAL STRUCTURE OF DINUCLEAR IRON CARBONYL DERIVATIVE (μ-SC_6H_5) (μ-P (SC_6H_5)_2) Fe_2 (CO)_5 (P-(SC_6H_5)_3)

<正> The reaction of Fe3(CO)12 with P(SPh)3 yields the tile compound. C41H30Fe2O5P2S6, Mr = 968. 65, monoclinic, space group, P21/n, a = 14. 449(9), b = 18. 046(11), c=16.871(10)(?), β=98. 76°, V = 4348(?)3, Z = 4, Dc=1. 480g/ cm3, λ(MoKα) = 0. 71073(?) The structure was determined by direct methods and difference Fourier syntheses and refined by full-matrix least-squares procedure to R = 0.084, Rw = 0.144 for 4059 reflections. Fe(1)-Fe(2) = 2. 576(6), Fe(2)-P(2) = 2.194(9)(?). The dihedral angle between the Fe(l)SFe(2) and Fe(1)PFe(2) planes is 81. 9°. The other one (dihedral angle between SFe(1)P and SFe(2)P planes) is 75. 2°.     

CRYSTAL STRUCTURE OF BIS (η~5-CYCLOPENTADIENYL)(1,3-PROPANEDIYL-BIS(DIPHENYL-PHOSPHINE)-P,P')NICKEL(II) DODECAHYDEO-DODECABORATE (C_5H_5Ni(C_6H_5)_2PC_3H_6P-(C_6H_5)_2)_2~ ·B_(12)H_(12)~(2-)

<正> Introduction. Tertiary diphosphine-cyclopentadienyl-nickel(Ⅱ) complexes were first synthesized by Sato (Sato, et al., 1971), and their boronhydrides were prepared by Zhang (Zhang, et al., 1983). Here we report the crystal structure of the title compound in Order to correlate the reactivity of this type of compounds with their structures and bondings.     

Indole derivatives. 138. Synthesis of α-(5-indolyl)ethylamine and 5-(2-aminoethoxy)- and 5-(aminoethylthio)tryptamines

The reaction of 5-acetylindole with hydroxylamine with subsequent reduction of the resulting oxime gave -(5-indolyl)ethylamine. Coupling of 4-(2-phthalimidoethoxy)- and 4-(2-phthalimidoethylthio)phenyldiazonium chlorides with ethyl -acetyl--phthalimidovalerate, subsequent cyclization of the resulting hydrazones, hydrolysis, decarboxylation, and removal of the phthalyl protecting group led to the formation of 5-(2-aminoethoxy)- and 5-(2-aminoethylthio)tryptamines, respectively.For Communication 137, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 46–48, January, 1992.     

锌(Ⅱ)-2-(6-甲基-2-苯并噻唑偶氮)-5-二乙氨基苯甲酸的显色反应研究

研究了2-(6-甲基-2-苯并噻唑偶氮)-5-二乙氨基苯甲酸(6-CH3-BTAEB)与锌显色反应的溶剂化效应和缓冲介质的影响。结果表明,在乙醇介质中,6-CH3-BTAEB与锌(Ⅱ)在(CH2)6N4-HNO3缓冲体系中可形成摩尔比为2∶1的蓝色络合物。该络合物的最大吸收波长为626 nm,表观摩尔吸光系数6ε26=7.7×104L.mol-1.cm-1,锌(Ⅱ)含量在0~8μg/10mL范围内遵守比耳定律。方法用于镁合金和模拟合金试样中痕量锌的测定,结果满意。     

Heats of formation of C(6)H(5)(•), C(6)H(5)(+), and C(6)H(5)NO by threshold photoelectron photoion coincidence and active thermochemical tables analysis

Threshold photoelectron photoion coincidence has been used to prepare selected internal energy distributions of nitrosobenzene ions [C(6)H(5)NO(+)]. Dissociation to C(6)H(5)(+) + NO products was measured over a range of internal energies and rate constants from 10(3) to 10(7) s(-1) and fitted with the statistical theory of unimolecular decay. A 0 K dissociative photoionization onset energy of 10.607 ± 0.020 eV was derived by using the simplified statistical adiabatic channel model. The thermochemical network of Active Thermochemical Tables (ATcT) was expanded to include phenyl and phenylium, as well as nitrosobenzene. The current ATcT heats of formation of these three species at 0 K (298.15 K) are 350.6 (337.3) ± 0.6, 1148.7 (1136.8) ± 1.0, and 215.6 (198.6) ± 1.5 kJ mol(-1), respectively. The resulting adiabatic ionization energy of phenyl is 8.272 ± 0.010 eV. The new ATcT thermochemistry for phenyl entails a 0 K (298.15 K) C-H bond dissociation enthalpy of benzene of 465.9 (472.1) ± 0.6 kJ mol(-1). Several related thermochemical quantities from ATcT, including the current enthalpies of formation of benzene, monohalobenzenes, and their ions, as well as interim ATcT values for the constituent atoms, are also given.     

双(6-氧-丁烯二酸单酯)-β-环糊精对钯(Ⅱ)-2-(5-溴-2-吡啶偶氮)-5-二乙氨基苯酚显色反应的作用及其应用

研究了双 (6-氧 -丁烯二酸单酯 ) -β-环糊精 (简称β- CD衍生物 )对 Pd( ) - 2 - (5-溴 - 2 -吡啶偶氮 ) - 5-二乙氨基苯酚 (简称 Pd( ) - 5- Br- PADAP)显色反应的增敏作用。在 p H=4.0～ 5.0的 HAc- Na Ac介质中 ,该体系最大吸收波长为 590 nm,表观摩尔吸光系数为 6.71× 1 0 4 L· mol-1· cm-1,钯 ( )含量在0～ 1 1 μg/1 0 m L范围内服从比尔定律。方法用于活性炭载体催化剂和矿样中钯的测定     

Asymmetric Conjugate Addition of Alcohols to (R)-(-)-5-[(1R,2S,5R)-Menthyloxy]-2-(5H)-Furanone

(R)-(-y5-[(IR,2S,5R)-menthyloxy](1)isausefulchiralsynthonreadilypreparedonatWo-stepprocedure-l']FindingsoffuranoneringsexistingascomponentSofsomenaturalproductSI'laswellastheiractivereactivityl']havestimu1atedeXtensiveresearchofitSasymmetricreactionswhichincludeDiels-Alderreactions,l']l,3-dipo1arcycloadditions,['1Michaelauditionsl5]andconjugateedditionsofaminesl']andmercaPtans.g4:,::7f:7':theseadductsledtovariousmultifunctionalhomochiralbuildingblockssuchas2-alkyl-l,4-butanediols,I'l2-aI…