Negative chemical ionization mass spectrometry of phenols,and their determination in acidic fractions of coal-derived liquids

The use of Freon–113 as a reagent gas in the negative chemical ionization mass spectra of phenolic compounds is reported. The dominant mode of ionization is by chloride attachment producing [M + Cl]^? ions. The application of this technique to the highly phenolic acid fractions from coal-derived liquids gives spectra containing essentially only [M + Cl]^? peaks. This allows relative molecular mass profiles to be obtained. The resultant complex spectra are simplified by dividing them into their homologous series components. Since this is a low-resolution technique, absolute component identification cannot be made; but in conjunction with other analytical methods, tentative identification of series of molecules is possible. Thus, the alkyl-substituent ranges of the different homologous series can be assessed. Comparisons between coal-derived liquids produced under different reaction conditions are made, and composition differences detected.     

Darstellung und NMR-spektroskopische charakterisierung einiger di-n-alkyl- und n-alkylaryl-chlorphosphane

A series of di-n-alkyl and n-alkylaryl chlorophosphines has been prepared by the reaction of tetraorganodiphosphines with chlorodiphenyl or dichlorophenyl phosphine and characterized by ³¹P and ¹³C NMR spectra.     

Synthesis and Steric Structure of Aroxypropynyl Alcohols of the Tetrahydropyran and Tetrahydrothiopyran Series

Optimal conditions have been developed for the synthesis and isolation of phenoxy- and benzyloxypropynyl alcohols of the tetrahydropyran and tetrahydrothiopyran series. The structures of individual isomers have been established on the basis of the ¹H and ^13C NMR spectra. The stereochemical results of the reaction depend on the initial ketone structure.     

Nuclear magnetic resonance spectra of polyalkylindoles obtained by transformations of 3-nitropyridenium salts

Data are correlated on the ¹E and ¹³C NMR spectra of a representative series of polyalkylindoles obtained by the reaction of alkyl-substituted 3-nitropyridinium salts with ketimines. It has been shown that the use of a combined approach to the interpretation of the ¹H and ¹³C NMR spectra enables reliable information to be obtained on the structure of these previously unknown indole derivatives. The long range ¹³C-H coupling constants give particularly valuable information. A reliable demonstration of the structure of the reaction products is the basis for establishing the route of the indolization.Dedicated to Professor A. R. Katritzky on his 65th birthday.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 899–906, July, 1993.     

3,6-二甲基-9-芳基-2,7-二氧杂-1,2,7,8,9,10-六氢-1,8-吖啶二酮衍生物的一步合成

以芳醛、6-甲基-4-羟基-2-吡喃酮、醋酸铵为原料, 醋酸为溶剂, 一步合成了一系列3,6-二甲基-9-芳基-2,7-二氧 杂-1,2,7,8,9,10-六氢-1,8-吖啶二酮, 产物的结构经红外、核磁、元素分析进行了表征, 并对反应过程提出了可能的机理.     

The loss of a methyl radical and the retro diels—Alder reaction in the electron impact mass spectrometry of 2-cyclohexen-1-ol and related compounds

The electron impact mass spectra of 2-cyclohexen-1-ol and of several of its ²H and ¹³C labelled analogues show that the molecular ions lose a methyl radical by a completely different means from the mechanism described previously. Moreover, the retro Diels–Alder reaction also proceeds in a non-classical way; in addition to the elimination of an olefinic molecule from unrearranged molecular ions, a second more important route implies a formal 1,3 allylic rearrangement prior to the retro Diels–Alder reaction. The mass spectra of a series of alkyl substituted homologues show that the competition between the two processes is closely related to the size of the olefinic moiety that is expelled.     

Synthesis and Optical Properties of Novel Carbazole Derivatives Containing Pyridine Ring

A series of novel monodisperse, well‐defined molecules with a pyridine core and carbazole arms were synthesized by simple procedures with Iodo‐reaction and Ullmann reaction. Their structures were confirmed by IR, ¹H NMR, ¹³C NMR, and elementary analysis. Moreover, the fluorescence spectra showed that these compounds exhibited strong fluorescence with the maximum wavelengths ranging from 373 to 385 nm.     

Synthesis of New Nitroamino-Containing 1,2,4-Triazines by Reaction of 1-Amino-2-nitroguanidine with α-Diketones

The reaction of 1-amino-2-nitroguanidine with α-diketones (butane-2,3-dione and 1,2-diphenylethanedione) produced new specimens of nitroamino-containing 1,2,4-triazines. The structure of the synthesized compounds of linear and heterocyclic series was confirmed by ¹H, ¹³C{¹H} NMR, IR, and UV spectra.     

A Microwave Promoted New Condensation Reaction of Aryl Ketones With Triethyl Ortho-Formate

Under microwave irradiation, boron trifluoride has been found to mediate a new condensation reaction of aryl ketones with triethyl orthoformate to give a series of new products (C1-C10) is described. The compounds were first reported. Their structure were determined by IR, MS, and ¹H /¹³C NMR spectra.     

硫代氢化脲嘧啶的合成及其对Hill反应的抑制活性

为了寻找高活性的Hill反应抑制剂, 以β-氨基丙酸为原料, 经过四步反应, 合成了一系列未经文献报道的3-取代硫代氢化脲嘧啶. 所有新化合物的结构均经过¹H NMR, IR和元素分析证. 初步的生物活性测试表明, 所合成的化合物能有效地抑制Hill反应, 如化合物 5j 有很高的抑制活性(IC₅₀＝0.82 g•mL^－1).     

N-(4-苯基-噻唑-2-基)芳醛腙类化合物的合成

以芳醛与氨基硫脲进行缩合得到缩氨基硫脲, 分别与ω-溴苯乙酮进行成环反应得到了一系列含噻唑环和芳基的腙类化合物, 并通过用¹H NMR、质谱、红外光谱等对化合物进行了结构表征.     

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.     

Reaction of 5,5-Dimethyl-2-oxotetrahydrofuran-4-ylacetohydrazide with Aldehydes and Ketones

The reaction of 5,5-dimethyl-2-oxotetrahydrofuran-4-ylacetohydrazide with a series of aldehydes and ketones led to the synthesis of systems which, according to the ¹H NMR spectra, exist exclusively in the linear form. According to the mass spectra, however, in the gas phase some of the compounds can also exist partly in the cyclic form. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 991–997, July, 2005.     

An unusual way of the reaction of PI3 with norbornene and norbornadiene

The iodination of norbornene and norbornadiene with phosphorus triiodide in the presence and in the absence of weak electrophiles (arylsulfenamides orN-chloramines) and with elemental iodine was studied. Depending on the reaction conditions, the reactions resulted in mono- or diiodides of the norbornene and norbornadiene series. All the compounds obtained were characterized by¹H and¹³C NMR spectra.     

Stereoselective synthesis of new vicinal diaminoalkyl naphthols by three component Mannich type reaction of α,β-unsaturated aldehydes

The application of the aromatic Mannich reaction to α,β-unsaturated aldehydes, affords a series of new diaminoalkyl naphthols, by a convenient solventless reaction, starting from inexpensive and easily available starting materials. The absolute configurations of the products obtained are attributed on the basis of the coupling constant values of ¹H NMR spectra, joined with the conformational analysis of the molecules by molecular modelling. A mechanistic hypothesis is proposed, which involves an imino–amino intermediate.     

N-(4-芳基-噻唑-2-基)--(1H-苯并三唑-1-基)苯乙酮腙类衍生物的合成

以苯并三唑为原料与-溴代芳基乙酮缩合得-(1H-苯并三唑-1-基)芳基乙酮, 再与硫代氨基脲缩合得到新的缩氨基硫脲. 然后分别与5种ω-溴代芳基乙酮环化得到一系列新的含苯并三唑和噻唑环的苯乙酮腙类Schiff碱. 其结构经IR, ¹H NMR, ¹³C NMR和MS及元素分析确证.     

三组分一锅法合成1-羧甲基-6-芳基-1,2,3,4,5,6-六氢茚并[2,3-b]-喹啉-5,11-二酮

以芳醛、1,3-茚二酮、烯胺酮为原料, 冰醋酸为溶剂, 三组分一锅法合成了一系列茚并[2,3-b]喹啉类化合物. 该反应产率高(83%～93%)、操作简单、后处理方便. 产物的结构通过红外光谱、核磁共振谱和元素分析证实, 同时给出了该反应可能的反应机理.     

Atroposelective Ring Opening of Cyclic Diaryliodonium Salts with Bulky Anilines Controlled by a Chiral Cobalt(III) Anion

The present work demonstrates a CuCl and anionic chiral cobalt(III)-catalyzed enantioselective ring-opening reaction. The small-size, ligand-free copper species enabled the cross-coupling of iodonium salts with a series of bulky aromatic amines in high ee values. The chiral cobalt(III) anion causes appreciable chemical shift changes of cyclic diaryliodoniums in ¹H NMR spectra.     

Synthesis of 3-(3-Alkyl-5-thioxo-1H-4,5-dihydro-1,2,4-triazol-4-yl)aminocarbonylchromones

A series of 3-(3-alkyl-5-thioxo-1H-4,5-dihydro-1,2,4-triazol-4-yl)aminocarbonylchromones has been prepared by oxidation of 3-formylchromone with Jones' reagent followed by reaction with 3-alkyl-4-amino-4,5-dihydro-1,2,4-triazole-5(1H)-thione in the presence of POCl³. The structures of the compounds were confirmed by IR, LC-MS, and ¹H NMR spectra and elemental analyses.     

Photoinduced hydrogen abstraction‐coupling reaction mechanism of Δ5‐steroids with substituted 1, 4‐benzoquinones via electron transfer pathways

The photochemical reaction between three A⁵‐steroids (1–3) and a series of substituted 1,4‐benzoquinones and their mechanistic study were reported. The reaction in nitrogen atmosphere led to the formation of three products including the steroid‐quinone coupling compound (A), 7‐hydroxy derivatives of Δ⁵‐steroids (B) and substituted 1, 4‐hydroquinone (C). Both chemical and spectrometric evidences such as UV‐Visible spectra, ESR, chemically induced dynamic nuclear polarization (CIDNP) and cyclic voltammetry (CV) verified that the title reaction underwent a predominant photoinduced electron transfer pathway via the triplet quinone.