One-Pot Synthesis of N-Alkyl Sulfonyl Hydrazones by Dialkyl Acetylenedicarboxylate-Mediated Reaction of Trialkylphosphites with Sulfonyl Hydrazones

Stable derivatives of N-alkyl sulfonyl hydrazone were obtained in excellent yields from the reaction between electron-deficient acetylenic ester compounds and sulfonyl hydrazones in the presence of trialkylphosphites in dichloromethan at room temperature.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]     

An Abnormal Reaction of N-(2,4-dinitrophenyl)-L-proline with Thionyl Chloride

N-(2,4-Dinitrophenyl)-4-amino-n-butyl aldehyde 3 was obtained with high yield of 80% when N-(2,4-dinitrophenyl)-L-proline 1 reacted with SOCl2 at room temperature,However,the anticipated product N-(2,4-dinitrophenyl)-Tetrahydropyrrolyl-2-(4-methylthiophenyl)ketone 2 did not be produced.The mechanism was discussed in this article.     

The Reactions of Dialkyl Phosphites and Phosphine Oxides with Iodosylbenzene

The reaction of iodosylbenzene with >P(O)H type of acids (dialkyl phosphites, secondary phosphine oxides) was studied. The acids of >P(O)H type add to iodosylbenzene to yield intermediate 6 which in the aprotic solvents yields oxidation products, it means >P(O)OH acids and/or anhydride of >P(O)OP(O)< type. On the other hand if the reaction is performed in alcohol as a solvent in the presence of sodium alcoholate >P(O)OR ester is the major product.     

The Reaction Activity of Aromatic Carbonyl Compounds with Diphenylphosphine Oxide Studied by 31P NMR

Abstract

A series of α-hydroxyphosphine oxides were prepared by the reactions of diphenylphosphine oxide and aromatic carbonyl compounds and characterized by ¹H NMR, ¹³C NMR, ³¹P NMR, FT-IR, ESI-MS, and HR-MS spectra. The reaction rates and experimental conditions of aromatic aldehydes and aromatic ketones were obviously different due to the activity of their carbonyls. The different substituents of the aromatic aldehydes affected the reaction rate too, and the quantitative reactivity of their substituent conformed to the Hammett equation. The results were confirmed by ³¹P NMR spectroscopy.     

Studies on the Reaction of Salicylic Acid with Dialkyl Phosphite by Electrospray Ionization Mass Spectrometry and 31p NMR

The Atherton-Todd reaction has been extensively applied to the synthesis of phosphates and phosphoroami dates. [1] Zeng et al. [2] suggested that under Atheron-Todd reaction conditions, dialkyl phosphites are transformed into diakyl phosphorochloridates.     

57Fe-Moessbauer and 13C-Cp-Mas NMR Spectroscopic Studies of Reaction Products of Ferrocenylruthenocene with Lewis Acids

Abstract

Adducts of ferrocenylruthenocene (I), ferrocenyl-ruthenocenylmethane (II) and biruthenocene (III) with Lewis acids were studies by means of ¹³C-CP-MAS NMR and ⁵⁷Fe- and ¹¹⁹Sn-Moessbauer spectroscopies. Large low-field shifts found in the ¹³C-CP-MAS NMR and large quadrupole splittings (Q. S.) found in the ⁵⁷Fe-Moessbauer and covalently bonded tin(IV) species found in the ¹¹⁹Sn-Moessbauer spectroscopic studies on the adducts suggest the presence of a direct chemical bonding between the central metal atoms in the metallocenes and the Lewis acids.     

The Kinetics and Mechanism of the Reaction of Onium Cyclopentadienylides with Tetrahalo-p-Benzoquinones

Abstract

The reaction of triphenylphosphonium cyclopentadienylide (1) with halogen-substituted p-benzoquinones (4) is shown to give a new class of dipolar (zwitterionic) dyes (5) containing phosphorus. The general structure of these molecules has been investigated by a combination of mass spectrometry and multinuclear (¹H, ^l3C and 3l^P) nmr using the specialist techniques of DEPT spectroscopy, homonuclear (COSY) and heteronuclear, 2-D nmr. In addition, stopped-flow (uv/vis) techniques have been used to study the kinetics of the reactions and hence demonsrate that the rate-limiting step is nucleophilic addition of the ylid to the quinone, followed by a rapid loss of halide ion. The mechanism follows the classical pattern associated with nucleophilic aromatic substitution in activated aryl halides.     

The Reaction of Selenium Trioxide with Dialkyl Ethers

The donor‐acceptor complexes Et₂O·SeO₃ and (Me₂O)₂·SeO₃ can be obtained as primary products by the reactions of selenium trioxide with dimethyl ether (Me₂O) and diethyl ether (Et₂O). The crystal and molecular structure of both complexes, which are stable below their melting points only, was determined by X‐ray structure analysis. Pairs of molecules Et₂O·SeO₃ form dimers due to two weak intermolecular Se···O contacts. No intermolecular interactions were observed in (Me₂O)₂·SeO₃. Trigonal bipyramidal coordination around Se^VI atoms in the latter complex is almost undistorted. Conversion of the adducts to dialkylesters of diselenic and selenic acid in the liquid phase was monitored by Raman, ¹H‐ and ⁷⁷Se‐NMR spectroscopy.     

镁与氯化铵水溶液反应机理的探讨

镁与冷水是无反应的,换句话说,其反应速度趋近于零。这是由于常温下纯水中氢离子浓度仅为10-7mol·L-1。将水加热至沸,因水的电离度增大,氢离子浓度随之增大到10-8mol·L-1,为原浓度的10倍;从而大大提高了反应速度,使镁得以从水中置换出氢气。     

Enhancement of Mercury Sorbent Using Metal Aluminate Carbonates with Chloride under Hydrothermal Conditions

Mercury sorbents M–Al–CO₃ (M=Mg²⁺, Mn²⁺, Fe²⁺, Cu²⁺, or Zn²⁺) were prepared by the coprecipitation of M^{2 +} and Al³⁺ in an alkaline NaOH/Na₂CO₃ solution. The formation of a layered double hydroxide structure significantly enhanced Hg removal, uniquely with a suitable binder as a support. Both Hg(NO₃ )₂ and HgCl₂ were used to perform the capture test. The calcined sorbent exhibited superior efficiency, particularly for materials having bivalent states of mixed oxide (MO), such as calcined Mn and Fe. Chloride ions effectively raised the mercury scrubber efficiency, regardless of the type of sorbent. The results show that synthetic sorbents can provide 96% removal of Hg at 200°C. In addition, a suitable binder such as TiO₂ can be used as a support for dispersing metal oxides, which significantly decreases the MO content while maintaining a high equivalent capture capacity.     

Investigation of Reaction Mechanism of Amino Acids and Phosphorus Trichloride by 31P NMR and ESI‐MS/MS

The reaction of amino acids and phosphorus trichloride in THF was studied by ³¹P NMR tracing and ESI‐MS/MS. A series of hydridophoranes and cyclic dipeptides were obtained. The reaction presented interesting diversity and the reaction mechanism was proposed. The mechanism suggests that phosphorus plays an important role in the synthesis of amino acid hydridophorane and cyclic dipeptides. The results also show that ³¹P NMR and ESI‐MS/MS are useful tools for the investigation of reaction mechanism.     

稀酸溶液中氯离子对工业纯铁的腐蚀机理研究

关于铁在酸性溶液中的腐蚀电化学行为，对不合特性吸附离子的体系而言，溶液PH值的改变对铁的阳极溶解起着重要作用，表明0＊一参与了钱的阳极溶解过程k’］．当向体系中引入具有特性吸附能力的执离子时，可以引起腐蚀中铁的腐蚀电位、Tdel斜率以及腐蚀电流密度和反应级教等诸多数的变化问，表明CI一也参与了铁腐蚀的电化学过程问．由于介质体系、电板材料及实验条件的差异，不同的研究者所获得的实验结果也不同卜和．然而，这些机理所讨论的均为把高于对阳极过程的影响，对氛离子存在时是否影响阴极析氢过程较少有实验证明．并且，对阳极…     

AlCl3催化作用下苯胺与CS2的反应机理初探

二苯硫脲是重要的医药和染料的中间体。常温常压下，用AlCl3作催化剂催化苯胺和CS2进行反应，可以高收率和高选择性地得到二苯硫脲。反应产物经GC／MS进行了检测，并提出了AlCl3催化苯胺和CS2的可能反应机理。     

六次甲基四胺与氯化钴室温固相反应机制的研究

室温固相反应作为一种高效、绿色的合成方法,在配位化合物、纳米材料、金属簇合物以及复合金属氧化物的合成中已经得到了广泛的应用[1￣6]。然而,到目前为止人们对室温固相反应的微观机制尚处于     

骨髓增生异常综合症患者血液红细胞^31P—NMR谱的特征

本文介绍了用３１Ｐ－ＮＭＲ谱研究骨髓增生异常综合症（ＭＤＳ）患者血液红细胞的方法。分析了患者和正常人的血液红细胞在３１Ｐ－ＮＭＲ谱上的差异，探讨这些差异在临床医学上对ＭＤＳ患者进行诊断和疗效跟踪检测的应用途径。     

The Reaction of SnCl2 with the Complexes cis-PtCl2 (phosphorus ligand)2 as studied by 31P and 195Pt NMR

The reactions of SnCl₂ with the complexes cis-PtCl₂P₂, P=trialkyl and triaryl phosphines and phosphites, in CDCl₃ and CD₂Cl₂ have been studied using ³¹P and ¹⁹⁵Pt NMR. methods. For equimolar amounts of Sn and Pt, products of the type PtCl(SnCl₃)P₂ are formed with the complex geometry depending on the nature of P. For P?PEt₃ and P(OPh)₃, further addition of SnCl₂ produces trans-Pt(SnCl₃)₂ complexes. The syntheses of trans-PtCl(SnCl₃) (PEt₃)₂ and trans-Pt(SnCl₃)₂ (OPh₃)₂ are described.     

Reaction of a cyclic triphosphenium ion with triflic acid and SnX2 (X = Br or Cl): A 31P NMR study

The di‐ium dication formed by triflic acid protonation of the cyclic triphosphenium ion derived from 1,4‐bis‐diphenylphosphinobutane, (dppb), and P₃(X = Br or Cl) decomposes via an acyclic dication bearing a  PHX group; this intermediate is reduced by SnX₂ in the presence of HX to yield a dication with a  PH₂ primary phosphane terminal group, which is comparatively stable. The structure of this species has been unequivocally confirmed by ³¹P solution‐state NMR spectroscopy. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:609–612, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20302     

31PNMR研究水生动物细胞死亡过程的动力学性质

由于细胞凋亡的研究有助于理解胚胎发育、免疫耐受、细胞群体稳定等重要生命现象, 并对治疗疾病具有潜在的价值, 故已成为研究的热点[1～5]. 已有文献报道, 细胞的死亡形式与细胞内ATP(三磷酸腺苷)的含量有关, 在细胞凋亡的过程中, 细胞内ATP的含量必须保持一定的水平[6,7]. 如在研究人的T-细胞死亡过程中, 发现当ATP的含量降低时, 细胞死亡的方式是坏死而不是凋亡[1,8]. 对于在细胞死亡过程中能量代谢物质的动态变化, Davis等[9]在对神经系统PC12细胞的凋亡过程的研究中发现, 尽管ATP的含量保持不变, 但Pi(无机磷)进入ATP和蛋白质的量明显减少, 进入磷酸肽的量明显增加. 以上结果表明, 可以利用31P NMR研究细胞的死亡过程. 本文首次利用31P NMR观测水生动物不同部位细胞死亡过程中ATP, PCr(磷酸肌酸), Pi和磷脂等能量代谢物质的含量变化并得到变化的速率常数, 所得结果有助于人们了解细胞死亡过程中能量代谢物质的变化规律和判断细胞死亡的快慢.     

Reaction between Furan‐ or Thiophene‐2‐carbonyl Chloride,Isocyanides, and Dialkyl Acetylenedicarboxy­lates: Multicomponent Synthesis of 2,2′‐Bifurans and 2‐(Thiophen‐2‐yl)furans

An efficient multi‐component synthesis of highly functionalized 2,2′‐bifurans and 2‐(thiophen‐2‐yl)furans is described. A mixture of furan‐ or thiophene‐2‐carbonyl chloride, an isocyanide, and a dialkyl acetylenedicarboxylate undergoes a smooth addition reaction in dry CH₂Cl₂ at ambient temperature to produce 2‐amino‐5‐(4‐chlorofuran‐2‐yl)furan‐3,4‐dicarboxylates and 2‐amino‐5‐(4‐chlorothiophen‐2‐yl)furan‐3,4‐dicarboxylates. A single‐crystal X‐ray‐analysis of a derivative conclusively confirms the structure of these 2,2′‐bifurans and 2‐(thiophen‐2‐yl)furans. A novel electrophilic aromatic substitution reaction can justify the formation of the Cl‐substituted furan or thiophene rings.