美国白蛾性信息素的合成研究进展

综述了自1982年美国白蛾性信息素被鉴定以来几种人工合成美国白蛾性信息素路线的最新进展，参考文献21篇。     

钯催化脱羰反应研究及若干昆虫性信息表的合成

综述了基于钯催化脱羰端烯化反应的若干昆虫性信息素的合成。     

葡萄透翅蛾性信息素

近年来,我们一直对透翅蛾类(sessidae)的昆虫性信息素感兴趣。透翅蛾是世界上广泛分布的蛀干性害虫,在我国主要的有七,八种,对森林、苗圃、果园造成很大经济损失。因此开展其性信息素的研究有一定的意义。     

昆虫性信息素共轭二烯的合成进展

许多昆虫性信息素具有共轭二烯的结构,它们的双键位置和几何构型是决定其生物活性的重要因素。立体选择性和区域选择性地合成共轭二烯是有机合成中十分有意义的研究课题。文章综述了昆虫性信息素共轭二烯的合成进展。     

光学活性昆虫性信息素类似物的新合成路线

本文首次报道用丙二酸二乙酯的相转移催化烃化产物经拆分并分别还原,氧化制得的光活性2-甲-戊烯-4-醛与一系列季鏻盐的Wittig反应。通过此反应共合成新的带有两个双键的光活性昆虫性信息素类似物20个,相应的外消旋物10个。该反应原料易得,反应条件温和,产率高,可作为这类化合物的通用方法。     

新型八字地老虎含氟性信息素类似物的合成及其生物活性

为了提高昆虫性信息素对八字地老虎防治效果,以阻断八字地老虎雌雄虫成虫间交配行为作为切入点,根据氟原子取代性信息素上的氢原子能够影响天然性信息素的化学、生物学和物理性质的机制。以性信息素前体醇为原料,经酯化反应合成6个新的八字地老虎含氟性信息素类似物(2a~2c, 3a~3c),其结构经¹H NMR, ¹³C NMR和HR-MS(ESI)表征。田间生物活性测试结果表明：配方SPA2,即2b/Z7-14 ∶Ac(1/10 000),剂量为1 000 μg的诱捕效果优于八字地老虎天然性信息素组分以及其他性信息素类似物。     

昆虫性信息素的固相合成

本综述阐明昆虫性信息素固相合成的最新成就。C.C.Leznoff 开创了昆虫性信息素的固相合成,并合成了一系列信息素。他以二醇为原料,以聚合物三苯甲基氯为保护剂。陈德恒等将保护剂改成聚合物三苯甲基氯硅烷,产率比前人有所提高。陈家威等大大改进了前两人的线路,简化了步骤,只抓住关键的一步进行固相合成,总产率比前人提高得更多。     

从柠檬醛合成梨圆蚧性信息素

从柠檬醛合成梨圆蚧性信息素张合胜，陈家威，徐章煌，蒋济隆（湖北大学化学系，武汉４３００６２）梨圆蚧，ＱｕａｄｒａｓｐｉｄｉｏｔｕｓＰｅｒｎｉｃｉｏｓｕｓ（Ｃｏ－ｍｓｔｏｃｋ）是对果林危害较大的害虫。该虫的性信息素包括两个组分：３－亚甲基－７－甲基－３...     

不饱和一元醇、乙酸酯和醛的合成

大多数鳞翅目昆虫性信息素是不饱和长碳链(C_(12)～C_(16))醇、乙酸酯或醛,双键位置一般在5、7、8、9、10和11位。它们的差别主     

钯催化脱羰反应研究及若干昆虫性信息素的合成

综述了基于钯催化脱羰端烯化反应的若干昆虫性信息素的合成     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Copper catalyzed/mediated synthetic methodology for ebselen and related isoselenazolones

Scope of the copper catalyzed/mediated selenium-nitrogen coupling reaction has been studied for the synthesis of isoselenazolones. It is noticed that the 2-chloro, 2-bromo-, and 2-iodo-aryl amides substrates can be exploited in the selenium-nitrogen coupling reaction by employing 25-100 mol % of CuI/1,10-phenanthroline (L) and potassium carbonate as a base in DMF. Furthermore, electron rich 2-chloro-arylamides also underwent selenium-nitrogen coupling reaction to give biologically important selenium-nitrogen heterocycles. Also, copper-catalyzed selenium-nitrogen coupling reaction has been meticulously applied for the synthesis of diaryl diselenides having methoxy, amine, and amide functionality from respective aryl iodides in the presence of stoichiometric amount of succinimide as an external Se-N coupling partner.     

Knoevenagel condensation catalyzed by novel Nmm-based ionic liquids in water

A series of novel N-methyl morpholine (Nmm) based ionic liquids with 1,2-propanediol group were synthesized and used as catalysts for Knoevenagel condensation at room temperature in water. Under the effect of the catalyst, various aldehydes or aliphatic ketones could react with a wide range of activated methylene compounds well, including malononitrile, alkyl cyanoacetate, cyanoacetamide, β-diketone, barbituric acid, 2-arylacetonitrile and thiazolidinedione. Furthermore, most of the products could be separated just by filtrating and washing with water. Additionally, the catalyst is recyclable and applicable for the large-scale synthesis.     

Construction of polyheterocyclic spirotetrahydrothiophene derivatives via sulfa-Michael/aldol cascade reaction

A series of polyheterocyclic spirotetrahydrothiophene derivatives were obtained in moderate to excellent yields via a catalyst-free sulfa-Michael/aldol cascade reaction of chalcones 1 and commercially available 1,4-dithiane-2,5-diol 2 under mild conditions. We also present the first asymmetric sulfa-Michael/aldol cascade reaction of chalcones 1 and commercially available 1,4-dithiane-2,5-diol 2 with moderate to good enantioselectivities catalyzed by readily available chiral phase-transfer catalysts (PTCs).     

Suzuki-Miyaura reactions of the soluble guanylate cyclase inhibitor NS2028: a non-product specific route to C-8 substituted analogues

Both soluble guanylate cyclase (sGC) inhibitors ODQ 1 and NS2028 2 are synthesized via improved protocols. In the former case treating 3,4-dihydroquinoxalin-2(1H)-one oxime 8, which can be prepared in two steps from 1,2-benzenediamine, with 1,1′-carbonyldiimidazole (CDI) gives the dihydro-ODQ 10 that in the presence of KMnO₄ oxidises to give ODQ 1 in an overall yield of 46% starting from 1,2-benzenediamine. In the latter case, the synthesis affords NS2028 2 from 2-amino-4-bromophenol 3 in three steps with an overall yield of 85% and avoids the need for chromatography. Furthermore, Suzuki-Miyaura reaction conditions are described that enable the preparation of 8-aryl and 8-heteroaryl derivatives of NS2028 directly from NS2028 2. Finally, demethylation of the 8-(methoxyphenyl) substituted analogues afforded the 8-(hydroxyphenyl) derivatives 40-42. All new products are fully characterised.