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%～     

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。     

高效液相色谱-二级管阵列检测器法测定化妆品中邻苯二甲酸酯

用甲醇将化妆品样品超声提取15min,离心、过滤,以XDB-C18分析枉分离分析,二级管阵列检测器检测,结合保留时间和光谱定性分析,采用高效液相色谱法测定化妆品中的邻苯二甲酸酯,外标法定量。邻苯二甲酸酯邻苯二甲酸丁基苄基酯（BBP）、邻苯二甲酸二丁酯（DBP）、邻苯二甲酸二（2-乙基已）酯（DEHP）在0．5-10．0mg／L浓度范围内均有良好的线性关系,相关系数r〉0．9998。BBP,DBP,DEHP在1．000,2．000mg／L添加水平的回收率为92％-105％,相对标准偏差（RSD）小于4％0=6）,检出限分别为14,12,6mg／kg。该方法适用于化妆品中BBP,DBP和DEHP含量的检测。     

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。     

快速提取-超高效液相色谱法测定唇膏中11种酞酸酯

建立快速提取–超高效液相色谱法测定唇膏中11种酞酸酯的检测方法。将唇膏样品涂覆在定量滤纸上,用甲醇涡旋超声提取,色谱柱采用Waters ACQUITY UPLC BEH C_(18)柱(100 mm×2.1 mm,1.7μm),流动相为乙腈–水,梯度洗脱,流量为0.5 mL/min,用PDA检测器检测,检测波长225 nm。以3倍空白噪音计,邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DEP)的检出限分别为1,2 mg/kg;邻苯二甲酸二丙酯(DPRP)、邻苯二甲酸二丁酯(DBP)、邻苯二甲酸二戊酯(DPP)、邻苯二甲酸二己酯(DHXP)、邻苯二甲酸丁基苄基酯(BBP)、邻苯二甲酸二(2–乙基)己酯(DEHP)、邻苯二甲酸二正辛酯(DNOP)的检出限为3 mg/kg;邻苯二甲酸二异壬酯(DINP)、邻苯二甲酸二异癸酯(DIDP)的检出限为30 mg/kg。方法的加标回收率为86.6%~98.6%,测定结果的相对标准偏差为0.6%~6.0%(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,结合色谱图和紫外光谱图,能快速准确测定唇膏中11种酞酸酯。     

薄层色谱扫描法测定塑料食品袋中酞酸酯的含量

建立了采用薄层色谱扫描测定塑料食品袋中4种酞酸酯(酞酸二甲酯(DMP)、酞酸二乙酯(DEP)、酞酸二丁酯(DBP)和酞酸二(2-乙基己基)酯(DEHP))的方法。经粉碎的样品先用乙醇浸泡24 h,然后超声提取,经0.45 μm滤膜过滤。点样在以丙酮处理过的硅胶G板上,以乙酸乙酯-无水乙醚-异辛烷(体积比为1∶4∶15)为展开剂展开,以双波长反射吸收飞点扫描测定(λS=275 nm,λR=340 nm),外标法定量。该法的线性关系较好，DMP、DEP、DBP和DEHP的检出限分别为2.1,2.4,3.4和4.0 ng,混合标准品在同一薄层板上的峰面积的相对标准偏差（RSD）为2.8%～3.5%，4种酞酸酯的样品加标回收率为78.58%～111.04%。该方法样品用量少,前处理简单,分离效果好,可用于塑料袋中4种酞酸酯的同时测定。经与气相色谱法的分析结果比较，两种方法对实际样品的分析结果接近。     

牛奶中酞酸酯污染物的气相色谱质谱-联用测定

建立了气相色谱.质谱法(GC-MS)测定市售牛奶中4种酞酸酯(邻苯二甲酸二乙酯(DEP)、邻苯二甲酸二异丁基酯(DiBP)、邻苯二甲酸二丁基酯(DBP),邻苯二甲酸二(2-乙基己基)酯(DEHP))的方法.样品采用乙酸乙酯直接萃取,C18小柱净化,过0.45μm滤膜,直接注入GC-Ms进行分析.保留时间定性,外标法定量.4种酞酸酯的回收率为77.9%～109.07%;精密度(RSD)为1.72%～6.18%;检测限在0.15～60 ng之间.     

高效液相色谱法测定塑料袋装食品中的邻苯二甲酸酯

采用高效液相色谱法测定用塑料袋盛装的食品中的邻苯二甲酸酯(PAEs),供试的食品为馒头、油饼、黄瓜和番茄.用同种塑料食品袋与纸袋分别盛装30 min,进行高速分散后超声波提取15 min,经弗罗里硅土层析柱净化,后用高效液相色谱进行分析,外标法定量.该方法的加标回收率为82.7%～107.6%,RSD为1.4%～6.9%,检出限DMP为0.988 ng,DEP为0.749 ng,DBP为0.702 ng,DEHP为1.920 ng.     

基于PA6纳米纤维膜固相萃取-液相色谱法检测牛奶中的邻苯二甲酸酯

采用静电纺丝法制备了聚酰胺6(PA6)纳米纤维膜,结合固相萃取技术-液相色谱法(HPLC-UV)检测了市售牛奶样品中的6种邻苯二甲酸酯(PAEs)的含量.对影响实验的各种因素,如提取溶剂的种类及用量、超声时间、洗脱溶剂的种类及用量、纳米纤维膜的用量、pH及过样速度等进行了考察.在最优化条件下,邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DEP)、邻苯二甲酸丁基苄酯(BBP)、邻苯二甲酸二丁酯(DBP)、邻苯二甲酸二(2-乙基己)酯(DEHP)和邻苯二甲酸二正辛酯(DOP)的检出限分别为0.02,0.01,0.05,0.05,0.10和0.25ng/mL.将该方法应用于不同品牌不同包装牛奶样品的检测,只需2.5mg PA6纳米纤维膜,即可完全萃取样品中的PAEs,相对标准偏差(RSD)小于5.82%,回收率为93.40%～104.83%.该方法测定牛奶中PAEs环境雌激素,检出限低,灵敏度高,结果准确可靠,重现性好.     

珠三角地区人群血浆中邻苯二甲酸酯的暴露水平研究

采用高效液相色谱-串联质谱(HPLC-MS/MS)法对珠三角地区人群血浆中16种邻苯二甲酸酯(PAEs)的暴露情况进行分析。样品预处理采用乙腈沉淀蛋白,正己烷液液萃取。结果表明,血浆中检出邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二异丁酯(DiBP)、邻苯二甲酸二正丁酯(DnBP)、邻苯二甲酸丁基苄基酯(BBP)、邻苯二甲酸二环己基酯(DCHP)与邻苯二甲酸二(2-乙基己基)酯(DEHP)。其中DEHP的检出率为100%;其次为DiBP、DnBP与DMP,检出率分别为98.0%、62.0%和49.0%;DCHP与BBP的检出率最低,均为5.00%。∑PAEs的含量为12.4～1 399 ng/g,中值与平均值分别为39.8、57.7 ng/g。6种PAEs中DEHP占比最高,为90.01%～99.96%。对不同性别与年龄人群的PAEs暴露水平进行研究,发现女性与低年龄组(≤40岁)人群血浆中的PAEs浓度较高,但仅DMP存在显著性差异。     

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%).     

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.     

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.     

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.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.