两种色谱法对塑料食品包装袋中邻苯二甲酸酯类化合物的分析

建立了毛细管气相色谱和薄层色谱测定5种邻苯二甲酸酯类化合物（邻苯二甲酸二甲酯（DMP）、邻苯二甲酸二乙酯（DEP）、邻苯二甲酸二丁酯（DBP）、邻苯二甲酸二正辛酯（DOP）和邻苯二甲酸二（2．乙基己基）酯（DEHP））的方法。样品用乙醇浸泡，超声提取，0．5p．m滤膜过滤。进行气相色谱和薄层扫描分析。气相色谱回收率：88．85％-120．19％，精密度RSD为1．6％-3．2％，检出限DMP、DEP、DBP、DOP和DEHP分别为2．0、1．8、2．6、3．2和3．1ng，两种方法均样品用量少，分离效果好。区别在于前者灵敏度、回收率高，后者样品前处理简单、费用低。各有优势。     

胶束扫集毛细管电动色谱法测定药物中3种邻苯二甲酸酯

采用胶束扫集毛细管电动色谱技术,建立了测定药物中邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DZP)和邻苯二甲酸二丁酯(DBP)的方法。电泳缓冲体系含80 mmol/L SDS,20 mmol/L NaH2PO4(pH 2.20),5%甲醇(V/V),分离电压-18 kV,重力进样80s×15.0cm,检测波长225 nm,使用Φ50μm×62.0 cm石英毛细管,有效长度50.0 cm。讨论了磷酸盐浓度、有机改善剂、SDS浓度、分离电压、进样时间等因素的影响,并考察了胶束扫集法对DMP、DEP和DBP的富集能力。在优化条件下,线性关系良好,相关系数大于0.9986,DMP、DEP和DBP的线性范围分别为1.25～240,1.04～200和1.56～200 mg/L,检出限分别为0.26,0.26和0.39 mg/L。方法应用于肠溶片中DMP、DEP和DBP的测定,回收率在93.3%～108%之间,RSD≤5.2%。每次样品测定可在10 min内完成。     

气相色谱法测定邻苯二甲酸酯

建立了气相色谱分析邻苯二甲酸酯的方法.选择邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DEP)、邻苯二甲酸二异丁酯(DIBP)、邻苯二甲酸二正丁酯(DBP)、邻苯二甲酸丁苄酯(BBP)、邻苯二甲酸二(2-乙基己基)酯(DEHP)、邻苯二甲酸二正辛酯(DOP)7种标物,对实验方法的准确程度进行了分析.7种标物的线性相关系数都能达到0.999以上,线性范围在0.01～1g/L之间;保留时间的相对标准偏差都在0.1%以内,峰面积的相对标准偏差在2%以内.     

计算机拟合技术研究C18柱在富集PAEs时的萃取条件

利用固相萃取技术富集了水中5种邻苯二甲酸酯类(邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DEP)、邻苯二甲酸二丁酯(DBP)、邻苯二甲酸二(2-乙基己基)酯(DEHP)、邻苯二甲酸二辛酯(DOP)).借助均匀设计法及计算机回归建模优化技术对5种PAEs的固相萃取条件进行了设计与优化,得到最佳固相萃取条件为: 洗脱剂配比: V(正己烷)∶V(丙酮)=30∶1,洗脱体积2 mL,洗脱流速为4 mL/min,上样流速8 mL/min.富集后的样品用带电子捕获检测器的毛细管气相色谱检测,方法的线性范围为1～1000 μg/L (DMP,DEP,DOP),0.2～100 μg/L (DBP,DEHP);线性回归方程的相关系数为0.9970～1.000,检出限为0.02～0.4 μg/L,方法回收率为69%～117%,相对标准偏差为2.2%～9.5%.     

超高效液相色谱法检测化妆品中邻苯二甲酸酯

建立了测定化妆品中4种邻苯二甲酸酯-邻苯二甲酸二甲酯(DMP),邻苯二甲酸二乙酯(DEP),邻苯二甲酸二丁酯(DBP),和邻苯二甲酸二(2-乙基己基)酯(DEHP)-的分析方法。用超高效液相色谱(UPLC)带PDA检测器,色谱柱:Acquity UPLCTMBEHC C18(50 mm×2.1 mmi.d.,1.7μm)。样品经乙腈提取后,用UPLC-PDA进行分析检测,结合保留时间和光谱进行定性分析,定量检测波长224nm。该法的回收率为94.3%~98.7%,精密度RSD为0.9%~2.6%,以10倍噪声计,DMP、DEP、DBP和DEHP的检出限分别为0.14、0.21、0.21、0.31ng。用该分析方法对115件化妆品样品进行了分析检测,29件化妆品检出DEP,14件DBP,25件DEHP。总检出阳性样品54件,总阳性检出率47.0%。其检出质量分数:2.5~4348.2μg/g。该方法分离效果好,灵敏度高,能够满足检测化妆品中4种邻苯二甲酸酯的需要。     

HPLC测定一次性塑料用品中邻苯二甲酸酯类增塑剂

本文用高压、液体色谱柱Liehmspher C-18(250mm×4.6mmID,5μm),以乙腈-水为流动相,流速为1.0mL/min,线性梯度乙腈从70%到100%,采用质谱检测器对邻苯二甲酸酯进行定性鉴定.邻苯二甲酸二甲脂(DMP)、邻苯二甲酸二乙酯(DEP)、邻苯二甲酸二丁酯(DBP)和邻苯二甲酸二甲酸辛酯(DOP)浓度分别为1.1～89mg/L,0.9～74mg/L,0.9～71mg/L和0.9～68mg/L时线性关系良好,平均回收率分别为83%,89%,86%,87%(n=5).建立了准确度和灵敏度高,方便快捷有效的一次性塑料用品中邻苯二甲酸酯类增塑剂的高效液相色谱定量分析方法.     

超声辅助分散液-液微萃取/高效液相色谱联用富集分析环境水样中邻苯二甲酸酯类化合物

建立了超声波辅助分散液-液微萃取(DLLME)与高效液相色谱(HPLC)联用对环境水样中痕量邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DEP)、邻苯二甲酸二丁酯(DBP)、邻苯二甲酸二(2-乙基己基)酯(DEHP)和邻苯二甲酸二辛酯(DOP)富集分离测定的方法,优化了色谱分离条件,考察了萃取剂与分散剂的种类与用量、萃取时间和离子强度对超声辅助DLLME/HPLC的影响。在优化实验条件下,邻苯二甲酸酯色谱峰面积与其浓度在1.00～100μg.L-1范围内呈良好的线性关系,相关系数均大于0.996,平均加标回收率为91%～103%,相对标准偏差(RSDs,n=5)为2.0%～6.8%,5种邻苯二甲酸酯类化合物的检出限(S/N=3)分别为0.08、0.04、0.03、0.01、0.07μg.L-1。建立的方法用于环境水样中邻苯二甲酸酯的测定,平均加标回收率为85%～119%,RSDs(n=3)为2.3%～11.1%。该方法适用于环境水样中痕量邻苯二甲酸酯类化合物的富集分析。     

超高效液相色谱法测定香型中性笔墨水中10种PAEs

建立超高效液相色谱–二极管阵列检测器测定香型中性笔墨水中邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DEP)、邻苯二甲酸二正丙酯(DPP)、邻苯二甲酸丁基苄酯(BBP)、邻苯二甲酸二正丁酯(DBP)、邻苯二甲酸二正戊酯(DAP)、邻苯二甲酸二环己酯(DCHP)、邻苯二甲酸二正己酯(DHP)、邻苯二甲酸二(2-乙基己基)酯(DEHP)和邻苯二甲酸二正辛酯(DNOP)10种邻苯二甲酸酯(PAEs)的方法。样品采用甲醇涡旋超声提取,色谱柱为Waters ACQUITY UPLC BEH C_(18)柱(100 mm×2.1 mm,1.7μm),以乙腈–水为流动相进行梯度洗脱,用PDA检测器检测,10 min内完成10种邻苯二甲酸酯的检测。10种邻苯二甲酸酯的质量浓度在5.0~200.0 mg/L范围内与其色谱峰面积呈良好的线性关系,线性相关系数均大于0.999,检出限为3.2~4.0 mg/kg;在高低两个添加水平下,10种邻苯二甲酸酯的回收率为96.3%~104.1%,测定结果相对标准偏差为0.1%~2.9%(n=6)。该方法样品处理简单,提取效率高,分离效果好,且灵敏度高,能快速准确测定香型中性笔墨水中10种邻苯二甲酸酯。     

毛细管气相色谱法测定化妆品中的酞酸酯

建立了用毛细管气相色谱配氢火焰离子化检测器测定化妆品中6种酞酸酯(邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DEP)、邻苯二甲酸二丁酯(DBP)、邻苯二甲酸丁基苄基酯(BBP)、邻苯二甲酸二(2-乙基己)酯(DEHP)和邻苯二甲酸二正辛酯(DOP))的方法。样品用甲醇超声提取,经高速冷冻离心,清液经干燥脱水过0.5 μm滤膜过滤,直接注入气相色谱仪进行分析。然后,经过气相色谱-电子电离-质谱检测分析,确证气相色谱-氢火焰检测的阳性检出结果。用保留时间定性,外标法定量。6种酞酸酯的回收率为82.90%～     

气相色谱法同时测定聚氯乙烯中的八种增塑剂

邻苯二甲酸酯作为增塑剂和耐寒剂已广泛应用于塑料制品中,但其致癌性也日益引起人们的关注。因此对增塑剂含量的分析和研究十分必要。本文用气相色谱法(GC)对聚氯乙烯(PVC)材料中的邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DEP)、邻苯二甲酸二丁酯(DBP)、邻苯二甲酸苄丁酯(BBP)、邻苯二甲酸双(2-乙基己)酯(DEHP)、邻苯二甲酸二异壬酯(DINP)、邻苯二甲酸二正辛酯(DNOP)、邻苯二甲酸二异癸酯(DIDP)等8种邻苯二甲酸酯的残留量进行了测定。方法简便、快速、灵敏。     

A carbanion induced synthesis of highly congested pyrazole and imidazole containing heterocycles

An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Selective synthesis of 4,5-dihydroimidazo- and imidazo[1,5-a]quinoxalines via modified Pictet–Spengler reaction

An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction.     

Understanding the Diels-Alder reactivity of 1,2-azaborine analogues

The Diels-Alder reactivity of 1,2-heteroborines (H₄C₄B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.     

Synthesis of N-substituted carbazolones from α-iodo enaminones via Pd(0)-catalyzed intramolecular coupling under microwave irradiation

A variety of N-aryl and N-alkyl carbazolones were conveniently achieved in good to high yields via Pd₂(dba)₃-mediated intramolecular coupling of N-substituted α-iodo enaminones under microwave irradiation. The Pd(0)-catalyzed cyclization was found to proceed favorably with the more electron-deficient phenyl ring during the reactions involving unsymmetrical N,N-diaryl α-iodo enaminones. This unique property enables the construction of carbazolone skeleton containing nitro substituted benzenoid ring.     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles by intramolecular nitrilimine cycloaddition

Both substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles have been synthesized by the 3+2 intramolecular dipolar cycloaddition of nitrilimines to alkynes. This cyclization has been extended to more versatile 3-bromo derivatives by the use of alkynylbromides as dipolarophiles.