火炬松挥发物的固相微萃取-气相色谱/质谱法分析

采用固相微萃取(SPME)技术,结合气相色谱/质谱(GC-MS)分析了火炬松枝条和针叶中的挥发性化合物,共鉴定了30种化学成分。其中枝条中分离鉴定出21种挥发性成分。主要成分为α-蒎烯、β-蒎烯、β-月蒎烯、反式-石竹烯、β-杜松烯、大根叶烯-D;针叶中分离鉴定出24种挥发性成分,主要成分为α-蒎烯、β-蒎烯、β-月桂烯、β-水芹烯、异长叶烯、反式-石竹烯、α-律草烯、大根叶烯-D、双环吉马烯和双环榄香烯。     

固相微萃取-气相色谱-质谱法分析香樟籽挥发性成分

采用固相微萃取-气相色谱-质谱法分离和鉴定香樟籽的挥发性成分,用归一化法测定其相对含量。共分离出76种组分,鉴定出47种化合物,其含量占总挥发性成分的97.4%。主要挥发成分为樟脑(57.89%)、柠檬烯(12.68%)、α-蒎烯(4.42%)、莰烯(2.69%)、香橙烯(2.34%)、伞花烃(2.26%)及β-蒎烯(2.12%)。     

马尾松、湿地松、油松针叶挥发物中手性单萜的组成与相对含量

采用动态顶空吸附／手性毛细管气相色潜-质谱（GC—MS）法，首次分析研究了马尾松（Pinus massoniana Lamb）、湿地松（Pinus elliottii Engelm）、油松（Pinus tabulaeformis Carr．）针叶挥发性化合物中主要手性单萜（α-蒎烯、莰烯、β-蒎烯、β-水芹烯、柠檬烯）的组成与相对含量，结果表明其在种间相差较大。马尾松中的（-）-α-蒎烯的含量（55．50％）最高，而其对映异构体（＋）-α／-蒎烯在油松中含量（16．86％）最高，（-）β-蒎烯在湿地松中含量（43．38％）最高。马尾松手性单萜的组成和含量在树与树间差异也较大。     

新型驱蚊产品中35种挥发性致敏芳香剂的筛查方法及挥发规律研究

基于顶空/气相色谱－串联质谱（HS/GC－MS/MS）建立了驱蚊贴、驱蚊扣、驱蚊手环等新型驱蚊产品中35种挥发性致敏芳香剂的分析方法。35种物质经中等极性色谱柱Agilent DB－17MS分离,采用电子轰击源（EI源）通过多反应监测（MRM）模式进行检测。考察了37个新型驱蚊样品在顶空温度分别为40 ℃和100 ℃时的筛查结果,40 ℃顶空条件下筛查出α-蒎烯、β-蒎烯和D-柠檬烯等14种致敏芳香剂,此外,100 ℃时还检出香叶醇、香芹酮等其它12种致敏芳香剂。以儿童用驱蚊贴和驱蚊扣为例,比较了不同顶空温度对各目标化合物响应强度的影响,结果表明,40 ℃时α-蒎烯、β-蒎烯和D-柠檬烯等8种致敏芳香剂的响应强度小于100 ℃时。对37个样品在40 ℃平衡温度下的半定量分析表明,α-蒎烯、β-蒎烯、D-柠檬烯等9种致敏芳香剂的检出率最高,其中α-蒎烯和D-柠檬烯的最高响应强度大于106。选择驱蚊贴和驱蚊扣进一步考察了α-蒎烯、β-蒎烯、D-柠檬烯、薄荷醇和樟脑5种致敏芳香剂在40 ℃下放置不同时间的挥发规律,发现α-蒎烯、β-蒎烯和D-柠檬烯放置12 h的响应强度为初始的20% ~ 21%,薄荷醇和樟脑放置72 h后响应强度仍为初始的40%以上。该研究可为后续开展新型驱蚊产品中化学物质的含量测定和风险评估提供技术参考。     

动态微波辅助顶空固相微萃取-气相色谱-质谱法测定芹菜叶中的化学成分

采用动态微波辅助顶空固相微萃取结合气相色谱-质谱法测定芹菜叶中的挥发性和半挥发性化学成分。对水蒸气蒸馏、顶空固相微萃取、微波辅助顶空固相微萃取、动态微波辅助顶空固相微萃取等4种不同的前处理方法进行了比较,通过气相色谱-质谱分析,分别鉴定出20,17,36,41种化学成分,主要化合物为α-月桂烯、柠檬烯、β-顺式罗勒烯、β-芹子烯和(Z)-3-己烯-1-醇等。结果表明:动态微波辅助顶空固相微萃取是一种简单、快速、易操作,无需净化步骤,消耗样品量少,对于沸点较高的半挥发性物质的萃取效果优于微波辅助顶空固相微萃取的方法,可用于分析各类植物中的挥发性和半挥发性化学成分。     

气相色谱-质谱联用法结合保留指数对高良姜挥发油成分的分析

采用气相色谱-质谱联用(GC-MS)法结合保留指数(RI)对高良姜水蒸气蒸馏法(SD)、超声波辅助溶剂提取法(UAE)和亚临界流体萃取法(SFE)所制备的挥发油进行分析,分别鉴定出51,46和60个挥发性组分,并通过峰面积归一化法确定各组分的相对含量。结果表明,高良姜挥发油的指标性成分1,8-桉叶素含量的大小顺序为SD法≈SFE法UAE法,UAE法虽耗时少、能耗低,但由于所用有机溶剂难去除,所得挥发油品质较差。SFE法可得到部分SD法无法得到的化合物,如2-羟基-1,8-桉叶素、二苯基庚烷类等。另外β-石竹烯、α-石竹烯、α-法尼烯、γ-杜松烯等高沸点组分比例,SFE法所得高于另两种方法;α-蒎烯、莰烯、β-蒎烯、柠檬烯、樟脑和α-松油醇等低沸点组分比例,SD法所得最高。同一批药材不同提取方法所得的挥发油成分大部分相似,但部分成分与组分比例因不同提取方法的原理存在差异,实际生产中可根据功效需求选择不同提取方法加以开发利用。     

气相色谱-质谱技术分析红松松塔挥发性成分

采用水蒸气蒸馏法,对红松松塔挥发性成分进行提取和研究,最佳蒸馏时间5.5 h,挥发油提取率1.28%.利用气相色谱-质谱联用技术对提取的挥发油成分进行分析,共鉴定出32种化学成分,主要为单萜和倍半萜类化合物,其中相对含量较高的有α-蒎烯(44.258%)、D-柠檬烯(23.426%)、β-蒎烯(8.674%)、石竹烯(3.462%)、β-月桂烯(3.018%)等.研究结果表明红松松塔挥发油中富含α-蒎烯、D-柠檬烯、石竹烯等多种具有药理活性的成分.因此,红松松塔是一种具有较好前景的天然药用资源.     

茼蒿挥发性成分的固相微萃取气相色谱-质谱分析

采用顶空固相微萃取技术富集茼蒿挥发性化合物，经气相色谱—质谱联用仪分析，共分离和鉴定了25个化合物；主要的化合物及相对含量为蒎烯38．6％、罗勒烯19．3％、2-己烯醛9．0％、1，6，10-十五碳三烯6．4％、乙酸冰片酯4．3％、大根香叶烯2．7％和金合欢烯1．1％等。     

气相色谱-质谱技术分析红松松塔挥发性成分

采用水蒸气蒸馏法，对红松松塔挥发性成分进行提取和研究，最佳蒸馏时间5.5h，挥发油提取率1.28％。利用气相色谱-质谱联用技术对提取的挥发油成分进行分析，共鉴定出32种化学成分，主要为单萜和倍半萜类化合物，其中相对含量较高的有α-蒎烯（44．258％）、D-柠檬烯（23．426％）、β-蒎烯（8.674％）、有石竹烯（3.462％）、β-月桂烯（3.018％）等。研究结果表明红松松塔挥发油中富含α-蒎烯、D-柠檬烯、石竹烯等多种具有药理活性的成分。因此，红松松塔是一种具有较好前景的天然药用资源。     

非极性溶剂微波萃取-气相色谱-质谱法测定白豆蔻中挥发油成分

提出了非极性溶剂微波萃取-气相色谱-质谱法测定白豆蔻中的挥发油成分的方法。优化的试验条件如下:①微波吸收介质为0.35g石墨粉;②提取溶剂为正己烷;③样品质量与溶剂容积之比为2g比25mL;④提取时间为30min。在气相色谱分离中用DB-5石英毛细管柱为固定相,在质谱分析中采用全扫描检测模式。以α-甲基苯甲醇丙酸酯为内标物。方法用于白豆蔻样品的分析,共鉴定出60种挥发性化学成分,主要化合物为桉油精(70.34%)、β-蒎烯(6.81%)、α-松油醇(3.36%)和α-蒎烯(2.54%)等。     

Crystal structure of (acetylacetonato) (dicarbonyl)iridium(I)

The structure of Ir(CO)₂(acac) is determined by XRD at room temperature. Crystallographic data for C₇H₇IrO₄ are: a = 6.4798(5) ?, b = 7.7288(5) ?, c = 9.1629(10) ?, α = 105.738(2)°, β = 90.467(3)°, γ = 100.658(2)°, space group 1, P , V= 433.24(6) ?³, Z = 2, d _calc = 2.662 g/cm³, R = 0.0167. The structure is built of isolated mononuclear molecules. The central iridium atom has a square coordination environment formed by two oxygen atoms that belong to the acetylacetonate ligand and two carbon atoms of carbonyl groups. The average Ir-O and Ir-C bond lengths are 2.045(3) ? and 1.832(6) ? respectively. Molecules are stacked in such a way that the planes of coordination squares turn out to be parallel to the Ir...Ir distances between the nearest neighbors in the stack of 3.242 ? and 3.260 ?. Original Russian Text Copyright ? 2009 by K. V. Zherikova, N. V. Kuratieva, and N. B. Morozova __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 3, pp. 595–597, May–June, 2009.     

Silylene hydride complexes of molybdenum with silicon-hydrogen interactions: neutron structure of (eta(5)-C(5)Me(5))(Me(2)PCH(2)CH(2)PMe(2))Mo(H)(SiEt(2))

Reduction of CpMoCl(4) with 3.1 equiv of Na/Hg amalgam (1.0% w/w) in the presence of 1 equiv of dmpe and 1 equiv of trimethylphosphine afforded the molybdenum(II) chloride complex Cp(dmpe)(PMe(3))MoCl (1) (Cp = 1,2,3,4,5-pentamethylcyclopentadienyl, dmpe = 1,2-bis(dimethylphosphino)ethane). Alkylation of 1 with PhCH(2)MgCl proceeded in high yield to liberate PMe(3) and give the 18-electron pi-benzyl complex Cp(dmpe)Mo(eta(3)-CH(2)Ph) (2). Variable temperature NMR experiments provided evidence that 2 is in equilibrium with its 16-electron eta(1)-benzyl isomer [Cp(dmpe)Mo(eta(1)-CH(2)Ph)]. This was further supported by reaction of 2 with CO to yield the carbonyl benzyl complex Cp(dmpe)(CO)Mo(eta(1)-CH(2)Ph) (3). Complex 2 was found to react with disubstituted silanes H(2)SiRR' (RR' = Me(2), Et(2), MePh, and Ph(2)) to form toluene and the silylene complexes Cp(dmpe)Mo(H)(SiRR') (4a: RR' = Me(2); 4b: RR' = Et(2); 4c: RR' = MePh; 4d: RR' = Ph(2)). Reactions of 2 with monosubstituted silanes H(3)SiR (R = Ph, Mes, Mes = 2,4,6-trimethylphenyl) produced rare examples of hydrosilylene complexes Cp(dmpe)Mo(H)Si(H)R (5a: R = Ph; 5b: R = Mes; 5c: R = CH(2)Ph). Reactivity of complexes 4a-c and 5a-d is dominated by 1,2-hydride migration from metal to silicon, and these complexes possess H.Si bonding interactions, as supported by spectroscopic and structural data. For example, the J(HSi) coupling constants in these species range in value from 30 to 48 Hz and are larger than would be expected in the absence of H.Si bonding. A neutron diffraction study on a single crystal of diethylsilylene complex 4b unequivocally determined the hydride ligand to be in a bridging position across the molybdenum-silicon bond (Mo-H 1.85(1) A, Si-H 1.68(1) A). The synthesis and reactivity properties of these complexes are described in detail.     

Syntheses and structures of the infinite chain compounds Cs(4)Ti(3)Se(13), Rb(4)Ti(3)S(14), Cs(4)Ti(3)S(14), Rb(4)Hf(3)S(14), Rb(4)Zr(3)Se(14), Cs(4)Zr(3)Se(14), and Cs(4)Hf(3)Se(14)

The alkali metal/group 4 metal/polychalcogenides Cs(4)Ti(3)Se(13), Rb(4)Ti(3)S(14), Cs(4)Ti(3)S(14), Rb(4)Hf(3)S(14), Rb(4)Zr(3)Se(14), Cs(4)Zr(3)Se(14), and Cs(4)Hf(3)Se(14) have been synthesized by means of the reactive flux method at 823 or 873 K. Cs(4)Ti(3)Se(13) crystallizes in a new structure type in space group C(2)(2)-P2(1) with eight formula units in a monoclinic cell at T = 153 K of dimensions a = 10.2524(6) A, b = 32.468(2) A, c = 14.6747(8) A, beta = 100.008(1) degrees. Cs(4)Ti(3)Se(13) is composed of four independent one-dimensional [Ti(3)Se(13)(4-)] chains separated by Cs(+) cations. These chains adopt hexagonal closest packing along the [100] direction. The [Ti(3)Se(13)(4-)] chains are built from the face- and edge-sharing of pentagonal pyramids and pentagonal bipyramids. Formal oxidation states cannot be assigned in Cs(4)Ti(3)Se(13). The compounds Rb(4)Ti(3)S(14), Cs(4)Ti(3)S(14), Rb(4)Hf(3)S(14), Rb(4)Zr(3)Se(14), Cs(4)Zr(3)Se(14), and Cs(4)Hf(3)Se(14) crystallize in the K(4)Ti(3)S(14) structure type with four formula units in space group C(2)(h)()(6)-C2/c of the monoclinic system at T = 153 K in cells of dimensions a = 21.085(1) A, b = 8.1169(5) A, c = 13.1992(8) A, beta = 112.835(1) degrees for Rb(4)Ti(3)S(14);a = 21.329(3) A, b = 8.415(1) A, c = 13.678(2) A, beta = 113.801(2) degrees for Cs(4)Ti(3)S(14); a = 21.643(2) A, b = 8.1848(8) A, c = 13.331(1) A, beta = 111.762(2) degrees for Rb(4)Hf(3)S(14); a = 22.605(7) A, b = 8.552(3) A, c = 13.880(4) A, beta = 110.919(9) degrees for Rb(4)Zr(3)Se(14); a = 22.826(5) A, b = 8.841(2) A, c = 14.278(3) A, beta = 111.456(4) degrees for Cs(4)Zr(3)Se(14); and a = 22.758(5) A, b = 8.844(2) A, c = 14.276(3) A, beta = 111.88(3) degrees for Cs(4)Hf(3)Se(14). These A(4)M(3)Q(14) compounds (A = alkali metal; M = group 4 metal; Q = chalcogen) contain hexagonally closest-packed [M(3)Q(14)(4-)] chains that run in the [101] direction and are separated by A(+) cations. Each [M(3)Q(14)(4-)] chain is built from a [M(3)Q(14)] unit that consists of two MQ(7) pentagonal bipyramids or one distorted MQ(8) bicapped octahedron bonded together by edge- or face-sharing. Each [M(3)Q(14)] unit contains six Q(2)(2-) dimers, with Q-Q distances in the normal single-bond range 2.0616(9)-2.095(2) A for S-S and 2.367(1)-2.391(2) A for Se-Se. The A(4)M(3)Q(14) compounds can be formulated as (A(+))(4)(M(4+))(3)(Q(2)(2-))(6)(Q(2-))(2).     

Trimethylphosphine complexes of tungsten(O) and (IV). X-ray crystal structures of trimethylphosphine tris (phenylacetylene) tungsten(O); bis(trimethylphosphine) tetrakis (methylisocyanide) tungsten(O), and oxodichlorotris (trimethylphosphine) tungsten (IV)

The reduction of WCl₄(PMe₃)₃ by sodium amalgam in presence of phenylacetylene gives W(PMe₃)(PhCCH)₃ (A). Reduction in presence of methylisocyanide gives W(PMe₃)₂(MeNC)₄ (B), while in presence of excess PMe₃ in tetrahydrofuran under hydrogen, WH₂Cl₂(PMe₃)₄ (C) is formed. The reaction of WCl₂(PMe₃)₄ with methanol in tetrahydrofuran gives mixtures of WH₂Cl₂(PMe₃)₄ and WOC1₂(PMe₃)₃ (D).The structures of A, B, and D have been determined by X-ray diffraction.