NEW ACYCLIC AND FUSED TRICYCLIC PHOSPHORUS COMPOUNDS AFFORDED BY NOVEL CONDENSATION

Abstract

The condensation of 1 - (2-benzothiazolyl)-4-phenylsemicarbazide with (R₂ N)₂ PX(X [dbnd] R₂N. RO, Ph) proceeds with cleavage of the N—C(O) bond and formation of the title compounds which were also synthesized via similar treatment of 2-hydrazinobenzothiazole in good yields. Reactivities of (R, N), PX, spectroscopic properties of the products and preliminary mechanism of these reactions were discussed.     

微波促进下1-芳甲酰基-4-(2′-苯并呋喃甲酰基)氨基硫脲及其衍生物的合成

微波辐射条件下 ,首先由 2 苯并呋喃甲酰氯在相转移条件下依次与硫氰酸铵和芳甲酰肼反应合成了一系列 1 芳甲酰基 4 ( 2′ 苯并呋喃甲酰基 )氨基硫脲 .进一步在微波辐射的条件下由这些氨基硫脲分别与碘酸钾、醋酸或醋酸汞等试剂作用高产率地制得了 1 芳甲酰基 4 ( 2′ 苯并呋喃甲酰基 )氨基脲、2 芳基 5 ( 2′ 苯并呋喃甲酰胺基 ) 1,3 ,4 噻二唑和 2 芳基 5 ( 2′ 苯并呋喃甲酰胺基 ) 1,3 ,4 二唑 .     

Apply peptide C-terminal semicarbazides to peptide segment coupling using transfer active ester condensation technology

Peptide C-terminal semicarbazides are used as the starting materials in transfer active ester condensation technology to prepare HOCt active esters intermediates, which react with other peptide segments or reagents to afford long chain peptides, branch peptides and peptide C-terminal derivatives. The semicarbazido derivatives afford reliable results and avoid side reactions efficiently.     

Transformations of peroxide ozonolysis products of natural olefins by <Emphasis Type="Italic">N</Emphasis>-containing organic compounds in methanol

Transformations of peroxide ozonolysis products of cyclic and acyclic natural olefins with different degrees of saturation by hydroxylamine and semicarbazide hydrochlorides were investigated. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 272–275, May–June, 2009.     

A Convenient Solid State Method for Preparing Aryl Azo Compounds

A convenient solid state reaction using ferric nitrate to oxidize substituted semicarbazide for preparing azo ureas has been reported for the first time. Eight phenyldiazenecarboxylic acid anilide derivatives, have been synthesized in excellent yields with cheap reagents and simple instruments under room temperature.     

Mechanism of positive iodine reactions: Kinetics of oxidation of semicarbazide by iodamine-T, iodine monochloride and iodine

Kinetics of oxidation of semicarbazide (SC) by iodamine-T (IAT), iodine monochloride and aqueous iodine has been studied in aqueous perchloric acid medium. The rate laws followed by the oxidation of SC were determined. The rates decreased slightly with increase in ionic strength of the medium in IAT and ICI oxidations, while the reverse trend was observed with I₂. Decrease in dielectric constant of the medium increased the rates with IAT and ICI, while it decreased the rate in I₂ oxidations. Addition of the reduced product,p-toluene-sulphonamide had no effect on the rate with IAT. Addition of I⁻ had slight negative and positive effects on the rates of oxidations with IAT and ICI, respectively, but the negative effect was considerable in I₂ oxidations. Mechanisms consistent with the observed rate laws have been proposed and discussed. Rate determining steps have been identified and their coefficients calculated. These constants were used to predict the rate constants from the deduced rate laws as [SC], [H⁺] and [I⁻] varied. Reasonable agreement between the calculated constants and experimental values provide support for the suggested mechanisms.     

氯化锌催化由氨基脲合成丫嗪的新方法

本文报道由芳香醛和盐酸氨基脲在无水氯化锌催化下一步生成丫嗪的新反应, 此方法具有简便,高产, 通用性强等特点.     

吡啶-4-甲醛缩氨基脲锌(Ⅱ)配合物的合成及其晶体结构

利用水热法合成了标题化合物[Zn(H4FoPyS)2(H2O)4](NO3)2.3(H2O)(1,H4FoPyS为希夫碱吡啶-4-甲醛缩氨基脲),其结构经IR,元素分析,单晶X-射线衍射和热重分析表征。1的晶体结构属三斜晶系,空间群P,īa=9.6505(16),b=12.644(2),c=13.156(2),α=115.459(3)°,β=90.0290(10),°γ=111.792(3),V=1321.1(4)3,Dc=1.609 g.cm-3,Z=2,M r=647.84,μ=1.905 mm-1和F(000)=728,最终偏差因子分别为R1=0.0365和wR2=0.0878。1中Zn(Ⅱ)是六配位的稍变形八面体构型,其中2个吡啶氮原子和2个配位水分子占据赤道平面,另外2个配位水分子处于轴向位置。     

Phenyl semicarbazide derivatives as corrosion inhibitors for aluminium in hydrochloric acid solution

Summary Measurements of the corrosion rate of aluminium in 2N HCl at 27°C with and without addition of phenyl semicarbazide derivatives (10^–3–10^–5 mol/l) were performed. The adsorption of these compounds was elucidated. Results show that phenyl semicarbazide derivatives are adsorbed on the aluminium surface according to the Frumkin isotherm. From the adsorption isotherm some thermodynamic data for the adsorption process (G° _ads . andf) are calculated and discussed.

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Phenylsemicarbazide als Korrosionsinhibitoren für Aluminium in salzsauren Lösungen

Zusammenfassung Es wurden Messungen der Korrosionsgeschwindigkeit von Aluminium in 2N HCl bei 27°C mit und ohne Zusatz von Phenylsemicarbaziden (10^–3–10^–5 mol/l) durchgeführt. Es wurde die Adsorption dieser Verbindungen untersucht, wobei sich zeigte, daß die Adsorption der Phenylsemicarbazidderivate der Frumkin-Isotherme gehorcht. Aus der Isotherme wurden einige thermodynamische Parameter des Adsorptionsprozesses (G° _ads. ,f) berechnet.

     

Studies on the Reaction of α‐Chloroformylarylhydrazine Hydrochloride with Imidazole and 1,2,4‐Triazole

α‐Imidazolformylarylhydrazine 2 and α‐[1,2,4]triazolformylarylhydrazine 3 have been synthesized through the nucleophilic substitution reaction of 1 with imidazole and 1,2,4‐triazole, respectively. 2,2′‐Diaryl‐2H,2′H‐[4,4′]bi[[1,2,4]‐triazolyl]‐3,3′‐dione 4 was obtained from the cycloaddition of α‐chloroformylarylhydrazine hydrochloride 1 with 1,2,4‐triazole at 60 °C and in absence of n‐Bu₃N. The inducing factor for cycloaddition of 1 with 1,2,4‐triazole was ascertained as hydrogen ion by the formation of 4 from the reaction of 3 with hydrochloric acid. 4 was also acquired from the reaction of 3 with 1 and this could confirm the reaction route for cycloaddition of 1 with 1,2,4‐triazole. Some acylation reagents were applied to induce the cyclization reaction of 2 and 3.1 possessing chloroformyl group could induce the cyclization of 2 to give 2‐aryl‐4‐(2‐aryl‐4‐vinyl‐semicarbazide‐4‐yl)‐2,4‐dihydro‐[1,2,4]‐triazol‐3‐one 6. 7 was obtained from the cyclization of 2 induced by some acyl chlorides. Acetic acid anhydride like acetyl chloride also could react with 2 to produce 7D . 5‐Substituted‐3‐aryl‐3H‐[1,3,4]oxadiazol‐2‐one 8 was produced from the cyclization reaction of 3 induced by some acyl chlorides or acetic acid anhydride. The 1,2,4‐triazole group of 3 played a role as a leaving group in the course of cyclization reaction. This was confirmed by the same product 8 which was acquired from the reaction of 1 , possessing a better leaving group: Cl, with some acyl chlorides or acetic acid anhydride.