高效液相色谱-串联质谱法同时测定肉类罐头中双酚-二缩水甘油醚

建立了同时测定肉类罐头中双酚A-二缩水甘油醚(BADGE)、双酚F-二缩水甘油醚(BFDGE)及其衍生物双酚A-(2,3-二羟丙基)甘油醚(BADGE•H2O)、双酚A-双(2,3-二羟丙基)醚(BADGE•2H2O)、双酚A-(3-氯-2-羟丙基)(2,3-二羟丙基)醚(BADGE•H2O•HCl)、双酚A-(3-氯-2-羟丙基)甘油醚(BADGE•HCl)、双酚A-双(3-氯-2-羟丙基)醚(BADGE•2HCl)、双酚F-双(2,3-二羟丙基)醚(BFDGE•2H2O)、双酚F-双(3-氯-2-羟丙基)醚(BFDGE•2HCl)9种环境激素的高效液相色谱-串联质谱分析方法。样品经叔丁基甲醚提取,HLB固相萃取小柱净化,C18色谱柱分离,用5 mmol/L醋酸铵溶液(含0.1%甲酸)与甲醇为流动相梯度洗脱,质谱多反应监测(MRM)模式检测,基质标准校正,外标法定量。结果表明,这9种化合物在10.0～2000.0 μg/L范围内线性关系良好;定量限(以信噪比≥10计)为10.0 μg/kg;在高、中、低3个加标水平下9种化合物的平均添加回收率为79.6%～100.9%,相对标准偏差为6.3%～12.1%。该方法具有较高的灵敏度和准确度,能满足法规要求的对肉类罐头中双酚A-二缩水甘油醚、双酚F-二缩水甘油醚及其衍生物残留量的快速检测及准确定量。     

Acyl Iodides in Organic Synthesis: VI. Reactions with Vinyl Ethers

Reactions of acetyl iodide with butyl vinyl ether, 1,2-divinyloxyethane, phenyl vinyl ether, 1,4-di-vinyloxybenzene, and divinyl ether were studied. Vinyl ethers derived from aliphatic alcohols (butyl vinyl ether and 1,2-divinyloxyethane) react with acetyl iodide in a way similar to ethyl vinyl ether, i.e., with cleavage of both O–Csp2 and Alk–O ether bonds. From butyl vinyl ether, a mixture of vinyl iodide, butyl acetate, vinyl acetate, and butyl iodide is formed, while 1,2-divinyloxyethane gives rise to vinyl iodide, vinyl acetate, and 2-iodoethyl acetate. The reaction of acetyl iodide with divinyl ether involves cleavage of only one O–Csp2 bond, yielding vinyl acetate and vinyl iodide. In the reactions of acetyl iodide with phenyl vinyl ether and 1,4-divinyloxybenzene, only the O–CVin bond is cleaved, whereas the O–CAr bond remains intact.     

Electrochemical fluorination of chlorine-containing ethers

The electrochemical fluorination of chlorine-containing ethers has been studied. In general, it was found that a chlorine bonded to an a-carbon atom in the ethers was readily removed during electrochemical reaction in anhydrous hydrogen fluoride, whilst a chlorine bonded to the β-carbon atom was retained to yield β-chlorinated polyfluoroethers.Through the use of this method, several new chloropolyfluoroethers, e.g. 2-chloro-1,1,2,2-tetrafluoroethyl difluoromethyl ether, 2,2-dichloro-1,1,2-trifluoroethyl trifluoromethyl ether 2,2-dichloro-1,1,2-trifluoroethyl difluoromethyl ether, 2,2-dichloro-1,1,2-trifluoroethyl chlorodifluoromethyl ether, 2-chloro-1,1,2,2-tetrafluoroethyl chlorodifluoromethyl ether and 2,2-trichloro-1,1-difluoroethyl trifluoromethyl ether, have isolated and characterized.     

冠醚桥接苯并菲二聚体合成的新途径

本研究借鉴合成冠醚的Willianmson反应,通过缓慢滴加二氯乙醚合成了重要中间体乙氧基醚链接的苯并菲二聚体,且避免了2,3-二羟基四戊烷氧基苯并菲自身成环反应所导致单一冠醚苯并菲的生成.进一步以该中间体为原料,通过缩合反应,最终得到了冠醚桥接苯并菲二聚体,并用1H NMR,13C NMR和MALDI-TOF质谱对产物的结构和纯度进行了表征.     

Gas-phase reactions of brominated diphenyl ethers with OH radicals

A small volume reaction chamber coupled to a mass spectrometer was used to study the gas-phase kinetics and mechanism of the reaction of OH radicals with diphenyl ether and seven polybrominated diphenyl ethers (PBDEs) with 1-2 bromines. Relative rate constants for these reactions were determined using isopropyl nitrite photolysis in He-air mixtures at approximately 740 Torr between the temperatures of 326-388 K. The Arrhenius expression for each compound was used to extrapolate the following OH rate constants at 298 K (in units of 10(-12) cm3 molecule(-1) s(-1), with 95% confidence intervals): diphenyl ether, 7.45 +/- 0.13; 2-bromodiphenyl ether, 4.7; 3-bromodiphenyl ether, 4.6; 4-bromodiphenyl ether, 5.7; 2,2'-dibromodiphenyl ether, 1.3; 2,4-dibromodiphenyl ether, 3.8; 3,3-dibromodiphenyl ether, 3.2; and 4,4'-bromodiphenyl ether, 5.1. The measured OH rate constants are in reasonable agreement with those predicted by structure activity relationships. Positive temperature dependences of these OH rate constants are observed for all compounds measured except for diphenyl ether and 4,4'-dibromodiphenyl ether. Bromophenols (in yields up to 20% relative to the amount of PBDE consumed) and Br2 were characterized as products of these reactions, suggesting that OH addition to ipso positions of these brominated aryls may be an important reaction pathway.     

Structural studies of organometallic compounds in solution: I. Magnesium iodide in diethyl ether and tetrahydrofuran

The structure of 2.8 M MgI₂ in diethyl ether solution and that of 1.7 M MgI₂ in tetrahydrofuran solution have been determined by large angle X-ray scattering measurements. The measurement on the diethyl ether solution was performed at 44°C, on a phase crystallizing at approximately 30°C. In diethyl ether a dimeric structure is found, arranged in a square-planar fashion. The bond lengths are: MgI 2.652(2), II (diagonal) 3.75(2) and II (linear) 5.30 Å. Three diethyl ether molecules are probably coordinated to each magnesium to complete an octahedral arrangement. In tetrahydrofuran the ion MgI⁺ from a dissociated complex predominates. In the MgI₂ complex a tetrahedral arrangement is found. In both the MgI⁺ and MgI₂ complexes the MgI distance is 2.56(2) Å. In the MgI₂ complex the II distance is 4.44(4) Å. In both solutions the MgO and MgC distances were kept fixed at 2.10 and 3.48 Å, respectively. The solubility of MgI₂ in diethyl ether has been shown to be strongly dependent on the water content of the ether; 0.2 M was the highest concentration obtained in anhydrous diethyl ether.     

Fast liquid chromatography-tandem mass spectrometry for the analysis of bisphenol A-diglycidyl ether, bisphenol F-diglycidyl ether and their derivatives in canned food and beverages

In this work a fast liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS) method using a C18 Fused Core™ column, was developed for the simultaneous analysis of bisphenol A diglycidyl ether (BADGE), bisphenol A (2,3-dihydroxypropyl) glycidyl ether (BADGE·H₂O), bisphenol A bis(2,3-dihydroxypropyl) ether (BADGE·2H₂O), bisphenol A (3-chloro-2-hydroxypropyl) glycidyl ether (BADGE·HCl), bisphenol A bis(3-chloro-2-hydroxypropyl) ether (BADGE·2HCl) and bisphenol A (3-chloro-2-hydroxypropyl)(2,3-dihydroxypropyl ether) (BADGE·HCl·H₂O) and bisphenol F diglycidyl ether (BFDGE), bisphenol F bis(2,3-dihydroxypropyl) ether (BFDGE·2H₂O), bisphenol F bis(3-chloro-2-hydroxypropyl) ether (BFDGE·2HCl). The LC method was coupled with a triple quadrupole mass spectrometer, using an ESI source in positive mode and using the [M+NH₄]⁺ adduct as precursor ion for tandem mass spectrometry experiments. The method developed was applied to the determination of these compounds in canned soft drinks and canned food. OASIS HLB solid phase extraction (SPE) cartridges were used for the analysis of soft drinks, while solid canned food was extracted with ethyl acetate. Method limits of quantitation ranged from 0.13 μg L⁻¹ to 1.6 μg L⁻¹ in soft drinks and 1.0 μg kg⁻¹ to 4.0 μg kg⁻¹ in food samples. BADGE·2H₂O was detected in all the analyzed samples, while other BADGEs such as BADGE·H₂O, BADGE·HCl·H₂O, BADGE·HCl and BADGE·2HCl were also detected in canned foods.     

Iridium-catalyzed carbonyl allylation by allyl ethers with tin(II) chloride

3-Alkoxypropenes, namely allyl ethers such as allyl butyl ether, allyl 2-hydroxypropyl ether, and diallyl ether, serve as reagents for the allylation of aldehydes with tin(II) chloride in the presence of a catalytic amount of [IrCl(cod)]₂ in THF and H₂O at 50 °C to produce the corresponding homoallylic alcohols.     

New approaches toward the synthesis of (D-homo) steroid skeletons using Mukaiyama reactions

New, short, and flexible procedures have been developed for syntheses of steroid and D-homo steroid skeletons. A Mukaiyama reaction between the silyl enol ether of 6-methoxytetralone and 2-methyl-2-cyclopentenone or carvone, with transfer of the silyl group to the receiving enone, gave a second silyl enol ether. Addition of a carbocation, generated under Lewis acid conditions from 3-methoxy-2-butenol, 3-ethoxy-3-phenyl-2-propenol or 3-methoxy-2-propenol to this second silyl enol ether gave adducts, which could not be cyclized by aldol condensation to (D-homo) steroid skeletons. The Mukaiyama-Michael reaction of the silyl enol ether of 6-methoxy tetralone with 2-methyl-2-cylopentenone gave a second silyl enol ether, which reacted in high yield with a carbocation generated from 3-hydroxy-3-(4-methoxyphenyl)propene. Ozonolysis of the double bond in this adduct gave a tricarbonyl compound (Zieglers triketone), which has been used before in the synthesis of 9,11-dehydroestrone methyl ether. A second synthesis of C17 substituted CD-trans coupled (D-homo) steroid skeletons has been developed via addition of a carbocation, generated with ZnBr₂ from a Torgov reagent, to a silyl enol ether containing ring D precursor. The obtained seco steroids have been cyclized under formation of the 8-14 bond by treatment with acid. The double bonds in one of the cyclized products have been reduced to a C17-substituted all trans steroid skeleton.     

Insertion Homo‐ and Copolymerization of Diallyl Ether

The previously unresolved issue of polymerization of allyl monomers CH₂?CHCH₂X is overcome by a palladium‐catalyzed insertion polymerization of diallyl ether as a monomer. An enhanced 2,1‐insertion of diallyl ether as compared to mono‐allyl ether retards the formation of an unreactive five‐membered cyclic O‐chelate (after 1,2‐insertion) that otherwise hinders further polymerization, and also enhances incorporation in ethylene polymers (20.4 mol %). Cyclic ether repeat units are formed selectively (96 %–99 %) by an intramolecular insertion of the second allyl moiety of the monomer. These features even enable a homopolymerization to yield polymers (poly‐diallyl ether) with degrees of polymerization of DP_n≈44.     

Etude dans la série des pyrrolidinones. IV. Formation de quelques dérivés de l'acide L méthylène bis N-(oxo-5 pyrrolidine carboxylique-2)

Starting from the readily available 5-oxo-2-carboxypyrrolidine, methylene-bis-(N-5-oxo-2-carboxypyrrolidine) was prepared and transformed into a diamine, then into two isomeric diols, which cyclised into one ether. The meso configuration has been assigned for this ether. The reduction of both diols and ether was complete and gave rise to methylene-bis-N-pyrrolidine.     

Side arm participation in lariat ether carboxylate-alkali metal cation complexes in solution

Lariat ether carboxylic acids of structure CECH₂OCH₂C₆H₄-2-CO₂H with crown ether (CE) ring sizes of 12-crown-4, 15-crown-5 and 18-crown-6 are prepared and converted into alkali metal-lariat ether carboxylate complexes. Absorptions for the diastereotopic benzylic protons in the ¹H NMR spectra of the complexes in CDCl₃ are utilized to probe the extent of side arm interaction with the crown ether-complexed metal ion as a function of the crown ether ring size and identity of the alkali metal cation.     

低取代度两亲性β-环糊精及其水相中纳米球的制备

将2-O-(2-羟丙基)-β-环糊精与十二烷基、十四烷基、十六烷基和十八烷基缩水甘油醚在吡啶中反应,合成了4个低取代度的两亲性β-环糊精衍生物(平均取代度分别为1.87、1.95、2.14和1.80)。 将上述4个化合物分散于水中自组装成可稳定2~3周的纳米球,并且均呈现出较好的分散度和均匀性。     

2]Rotaxanes containing pyridinium-phosphonium axles and 24-crown-8 ether wheels

A triethylphosphonium group attached to a pyridinium ethane moiety can be used as an axle for the self-assembly of [2]pseudorotaxanes and [2]rotaxanes. Although [2]pseudorotaxane formation is limited due to the bulk of the PR4+ group, [2]rotaxanes can be formed utilising 24-crown-8 ether, benzo-24-crown-8 ether and naphtho-24-crown-8 ether. The synthesis of these [2]rotaxanes and the X-ray structure of the [2]rotaxane containing a 24-crown-8 ether wheel are described. When the crown ether contains an aromatic group two possible conformational isomers exist; these are identified at low temperature by 1H and 31P NMR spectroscopy.     

Preparation and properties of poly(alkyl vinyl ether-2-ethyl-2-oxazoline) diblock copolymers

A method for the synthesis of well-defined poly(alkyl vinyl ether–2-ethyl-2-oxazoline) diblock copolymers with hydrolytically stable block linkages has been developed. Monofunctional poly(alkyl vinyl ether) oligomers with nearly Poisson molecular weight distributions were prepared via a living cationic polymerization method using chloroethyl vinyl ether together with HI/ZnI₂ as the initiating system and lithium borohydride as the termination reagent. Using the resultant chloroethyl ether functional oligomers in combination with sodium iodide as macroinitiators, 2-ethyl-2-oxazoline was polymerized in chlorobenzene/NMP to afford diblock copolymers. A series of poly(methyl vinyl ether–2-ethyl-2-oxazoline) diblock materials were found to have polydispersities of ≈ 1.3–1.4 and are microphase separated as indicated by two T_g's in their DSC thermograms. These copolymers are presently being used as model materials to study fundamental parameters important for steric stabilization of dispersions in polar media. © 1993 John Wiley & Sons, Inc.     

(Solid + liquid) phase equilibria of binary mixtures containing N-methyl-2-pyrrolidinone and ethers at atmospheric pressure

Solid–liquid equilibria (SLE), have been measured from 270 K to the boiling temperature of the solvent for 10 binary mixtures of N-methyl-2-pyrrolidinone, with ethers (dipropyl ether, dibutyl ether, dipentyl ether, methyl 1,1-dimethylethyl ether, methyl 1,1-dimethylpropyl ether, ethyl 1,1-dimethylpropyl ether, 1,4-dioxane, tetrahydrofuran, tetrahydropyran, 18-crown-6) using a dynamic method. The solubility of N-methyl-2-pyrrolidinone in ethers is lower than in alcohols and generally decreases with an increase of the number of carbon atoms of ether chain. The highest intermolecular solute–solvent interaction is observed for the cyclic ethers and for methyl 1,1-dimethylethyl ether.Experimental solubility results are compared with values calculated by means of the Wilson, UNIQUAC ASM and two NRTL equations utilizing parameters derived from SLE results. The existence of a solid–solid first-order phase transition in 18-crown-6 ether has been taken into consideration in the calculations. The correlation of the solubility data has been obtained with the average root-mean-square deviation of temperature σ_T = 0.9 K with UNIQUAC ASM and two NRTL equations and 0.6 K with the Wilson equation.     

多壁碳纳米管固相萃取-高效液相色谱-串联质谱法测定食品接触材料中双酚-二环氧甘油醚的迁移量

建立了测定食品接触材料中6种双酚-二环氧甘油醚(双酚A二缩水甘油醚(BADGE)及其衍生物双酚A(2,3-二羟丙基)甘油醚(BADGE•H2O)、双酚A(3-氯-2-羟丙基)甘油醚(BADGE•HCl)、双酚A(3-氯-2-羟丙基)(2,3-二羟丙基)醚(BADGE•H2O•HCl)和双酚F二缩水甘油醚(BFDGE)及其衍生物双酚F双(3-氯-2-羟丙基)甘油醚(BFDGE•2HCl))迁移到食品中的迁移量的高效液相色谱-串联质谱法(HPLC-MS/MS)。样品以叔丁基甲醚(MTBE)为提取溶剂,超声提取,提取液经多壁碳纳米管(MWCNTs)固相萃取(SPE)柱富集、净化。以COSMOSIL C18为分析柱,流动相为0.1%甲酸的5 mmol/L醋酸铵溶液和甲醇。6种双酚-二环氧甘油醚在1.0～100 μg/L范围内线性关系良好(r2＞0.9991)。在3个添加水平下,6种目标化合物的回收率范围为78.6%～89.9%,相对标准偏差小于10%。方法检出限范围为0.5～1.5 μg/L。该方法操作简单,灵敏度高,可应用于食品接触材料中双酚-二环氧甘油醚迁移量的快速检测。     

Synthesis and Cation Recognition Study of Novel Benzo Crown Ether Functionalized Enamine Derivatives

A novel series of benzo crown ether (dibenzo 18-crown-6 ether, benzo 18-crown-6 ether, and benzo 15-crown-5 ether) functionalized enamines derivatives from amino benzo crown ether (4-amino dibenzo 18-crown-6 ether, 4-amino benzo 18-crown-6 ether, 4-amino benzo 15-crown-5 ether) and substituted 3-(dimethylamino)-1-phenylprop-2-en-1-one compounds have been synthesized. All the synthesized compounds were characterized by infrared, ¹H NMR, ¹³C NMR, distortionless enhancement polarization transfer, and mass and elemental analysis techniques. The cation recognition property for benzo crown ether enamine 8a was studied by absorption and fluorescence spectroscopy.     

Simultaneous determination of NOGE-related and BADGE-related compounds in canned food by ultra-performance liquid chromatography–tandem mass spectrometry

An improved analytical method enabling rapid and accurate determination and identification of bisphenol F diglycidyl ether (novolac glycidyl ether 2-ring), novolac glycidyl ether 3-ring, novolac glycidyl ether 4-ring, novolac glycidyl ether 5-ring, novolac glycidyl ether 6-ring, bisphenol A diglycidyl ether, bisphenol A (2,3-dihydroxypropyl) glycidyl ether, bisphenol A (3-chloro-2-hydroxypropyl) glycidyl ether, bisphenol A bis(3-chloro-2-hydroxypropyl) ether, and bisphenol A (3-chloro-2-hydroxypropyl) (2,3-dihydroxypropyl) ether in canned food and their contact packaging materials has been developed by using, for the first time, ultra-performance liquid chromatography coupled with tandem mass spectrometry. After comparison of electrospray ionization and atmospheric pressure chemical ionization in positive and negative-ion modes, tandem mass spectrometry with positive electrospray ionization was chosen to carry out selective multiple reaction monitoring analysis of novolac glycidyl ethers, bisphenol A diglycidyl ether, and its derivatives. The analysis time is only 5.5 min per run. Limits of detection varied from 0.01 to 0.20 ng g(-1) for the different target compounds on the basis of a signal-to-noise ratio (S/N) = 3; limits of quantitation were from 0.03 to 0.66 ng g(-1). The relative standard deviation for repeatability was <8.01%. Analytical recovery ranged from 87.60 to 108.93%. This method was successfully applied to twenty samples of canned food and their contact packaging materials for determination of migration of NOGE, BADGE, and their derivatives from can coatings into food.     

Solubility of benzilic acid in select organic solvents at 298.15 K

Experimental solubilities are reported for benzilic acid dissolved in ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, 2-propanol, 2-butanol, 2-methyl-1-propanol, diethyl ether and methyl tert-butyl ether at 298.15?K. Results of these measurements reveal that the observed solubilities in the nine alcohol solvents fall within a fairly narrow mole fraction range of each other. Benzilic acid is also very soluble in the two ether solvents studied.