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1.
梨圆蚧是对果林危害较大的害虫。该虫的性信息素包括三个组分:3-亚甲基-7-甲基-7-辛烯-1-醇丙酸酯(1)、(2Z)-3,7-二甲基-2,7-辛二烯-1-醇丙酸酯(2)和(2E)-3,7-二甲基-2,7-辛二烯-1-醇丙酸酯(3)。本文介绍了通过对月桂烯进行结构改造来合成梨圆蚧性信息素,从月桂烯到1,总产率为19%。工业上从月桂烯制龋萑花醇和香叶醇,再将橙花醇和香叶醇转变为相应的氯烯醇后再还原、丙酰化即得2和3,其总产率分别为30%和28%。(以橙花醇和香叶醇计)。月桂烯可从β-蒎烯裂解而得。我国有丰富的蒎烯资源,所以开辟从月桂烯合成梨圆蚧性信息素的新途径具有重要的意义。 相似文献
2.
The title adduct was converted into 1,2-epoxymyrcene; its cationic 5-exo-cyclization gave a (±)-hop ether having the iridane-type skeleton. Effective syntheses of a furanoterpene perillene and some functionalized cyclopentanoid monoterpenes regioisomeric to iridoids were elaborated using sulfur-containing geraniol derivatives easily accessible from the same adduct in a synthetic sequence including the Pummerer reaction and anionic cyclization.Deceased Nov., 1, 1992.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 113–117, January, 1993. 相似文献
3.
微波固相法制备ZnCl2/NaY催化剂ZnCl2/NaY在月桂烯Diels-Alder反应中的催化性能 总被引:13,自引:0,他引:13
比较了微波固相法、普通加热法和简单混合法制备的ZnCl2/NaY及溶液离子交换法制备的ZnNaY在月桂烯与丙烯醛Diels-Alder反应中的催化性能,发现微波固相法制备的催化剂表现出最高的环加成选择性和区域选择性.通过对微波固相法制备的催化剂中ZnCl2负载量的考察,揭示了微波诱导ZnCl2在NaY分子筛表面形成了不同催化活性中心的特点,分散在分子筛表面的ZnCl2具有更高的催化活性和区域选择性.微波辐射可成功地将ZnCl2固载于NaY分子筛中,当ZnCl2负载量为6.3%时,ZnCl2与NaY分子筛主要发生固态离子交换反应;当ZnCl2负载量达25%时,催化活性提高了3倍,区域选择性提高了1倍以上.而且,以微波固相法制备的ZnCl2/NaY催化剂,其环加成选择性和区域选择性随反应温度的升高而下降. 相似文献
4.
新疆一枝蒿挥发油化学成份的研究 总被引:2,自引:0,他引:2
新疆一枝蒿挥发油有明显的抗过敏作用。通过 GC/MS/DS 分析,表明有三十九种化学成份,并确证了其中十八种的结构及含量。 相似文献
5.
Justin M. Delancey Matthew D. Cavazza Matthew G. Rendos Cory J. Ulisse Susan G. Palumbo Robert T. Mathers 《Journal of polymer science. Part A, Polymer chemistry》2011,49(17):3719-3727
Renewable resources have been utilized to control the degree of crosslinking during ring‐opening metathesis polymerizations (ROMP). In this regard, the addition of monoterpenes to thermosets created a sustainable method for adjusting the physical properties and thermal stability. A number of monoterpenes with alkenes were examined as monofunctional reactants. The presence of these monoterpenes, such as β‐pinene, during the ROMP of dicyclopentadiene altered the degree of crosslinking and plasticized the thermoset. The resulting physical properties were tailored to obtain desired modulus and glass transition (Tg) temperatures. The influence of time, temperature, weight percent β‐pinene, and different metathesis catalysts was examined by dynamic mechanical analysis, thermogravimetric analysis, and FTIR spectroscopy. A comparison of β‐pinene with other monoterpenes, such as carvone, limonene oxide, myrcene, and d‐limonene, resulted in a reactivity profile for this general method. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
6.
Jaime Gonzlez‐Villa Enrique Saldívar‐Guerra Ramn Enrique Díaz de Len‐Gmez Hctor Ricardo Lpez Gonzlez Jos Ramiro Infante‐Martínez 《Journal of polymer science. Part A, Polymer chemistry》2019,57(21):2157-2165
The kinetics of isothermal anionic homopolymerization of ß–myrcene (MYR) and 4–methylstyrene (4MS) in cyclohexane, initiated by n–butyllithium was studied at different temperatures (55, 63, and 71 ° C). The kinetic information obtained from the homopolymerizations was used to estimate the parameters of the Eyring equation, ΔH?= 84080 J/mol and ΔS?= ?21.9 J/mol·K for the MYR, and ΔH?= 51250 J/mol and ΔS?= ?116.8 J/mol·K for the 4MS, to calculate the apparent propagation coefficients as a function of temperature. Finally, the parameters obtained for the Eyring equation were validated by applying them in a mathematical model representing the kinetics of nonisothermal (quasi‐adiabatic) polymerization experiments of MYR and 4MS. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2157–2165 相似文献
7.
Saliha Loughmari Abderrafia Hafid Aicha Bouazza Abdelaziz El Bouadili Philippe Zinck Marc Visseaux 《Journal of polymer science. Part A, Polymer chemistry》2012,50(14):2898-2905
Polymerization of β‐myrcene with neodymium borohydride‐based coordination catalysts is very efficient, affording poly‐β‐myrcene (polymyrcene, PMy) with high selectivity. With stoichiometric amounts of n‐butylethyl magnesium (BEM) as co‐catalyst, good control over macromolecular data along with cis‐stereoselectivity up to 98.5%, are obtained. In the presence of excess BEM, high level of transfer reactions efficiency between neodymium and magnesium is clearly evidenced whereas the selectivity switches to 3,4‐rich. Combining the neodymium pre‐catalyst with triisobutyl aluminum in the presence of a boron activator affords PMy in good yield, but the polymer material displays low solubility, likely due to the occurrence of crosslinking. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
8.
Kasi DhanalakshmiMichel Vaultier 《Tetrahedron》2003,59(50):9907-9911
The ionic liquid 1-ethyl-3-methylimidazolium triflimide was used successfully as the reaction medium to carry out the rhodium catalysed coupling of myrcene with the active methylene compound ethyl acetoacetate in the presence of TPPMS as the ligand. Coupling product was obtained in 93% isolated yield without any side product formation when a 1:50 ratio of rhodium catalyst/TPPMS was used. 相似文献
9.
《Journal of polymer science. Part A, Polymer chemistry》2018,56(8):860-878
Bulk nitroxide‐mediated polymerization (NMP) of β‐myrcene (My)/glycidyl methacrylate (GMA) mixtures with varying GMA molar feed fraction (fGMA,0 = 0.10–0.91) was accomplished at 120 °C, initiated by SG1‐based alkoxyamine bearing a N‐succinimidyl ester group (NHS‐BlocBuilder). Low dispersity My/GMA copolymers (Đ < 1.56) with slight number‐average molecular weights (Mns) deviations from predicted values (Mn,theo with Mn/Mn,theo > 70%) were obtained. The copolymerization was revealed to be statistical, confirmed via Fineman–Ross (rMy = 0.80 ± 0.31 and rGMA = 0.71 ± 0.15) and Kelen‐Tüdös (rMy = 0.48 ± 0.12 and rGMA = 0.53 ± 0.18) approaches. Glass transition temperature (Tg) of the statistical P(My‐stat‐GMA)s increased from −77 to +43 °C as the GMA molar fraction incorporated (FGMA) increased from 0.10 to 0.90. High SG1 chain‐end fidelity for My‐rich and GMA‐rich P(My‐stat‐GMA)s was assessed by phosphorus nuclear magnetic resonance (31P NMR, SG1 fraction >69 mol %) and chain‐extensions in toluene with My, GMA and styrene (S) (monomodal shift in Mn). Last, diblock P(My‐b‐GMA) was made and treated with morpholine to produce amphiphilic copolymer able to self‐organize into micelles. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 860–878 相似文献
10.
报道了以叶绿素(Chl)为敏化剂、香叶烯光敏氧化的同时用四丁基硼氢化铵(TBABH4)还原得到相应的二级和三级烯丙基醇。讨论了玫瑰红(RB)、甲素(HA)和叶绿素三种敏化剂对产物分布的影响。实验结果表明:以叶绿素为敏化剂由香叶烯合成的齿小蠹二烯醇(Ipsdienol,2-甲基-6-甲叉基-2,7-辛二烯-4-醇),副产物少,收率较高。还讨论了还原剂的用量及光照时间对产物的影响。 相似文献