Pheromone study on acarid mites. Part IX. Syntheses of alarm pheromone analogues of the mold mite, Tyrophagus putrescentiae, and their biological activities.
摘要:
针对霉菌螨(Tyrophagus putrescentiae),3, 7-二甲基-(Z)-2-辛烯酸甲酯(II)是除了天然信息素(奈尔酸甲酯 I)外,作为警报信息素最活跃的化合物,其活性与 I 相当(1-10ppm)。为了阐明诱导警报信息素活性的结构要求,制备了16个 I 的类似物,通过改造 II 的结构。为制备3-甲基和3-乙基-(Z)-2-烯酸甲酯,采用了乙氧基或甲氧基碳酰基甲烯三苯基膦与2-烷酮或3-烷酮的威蒂格反应。与2-烷酮的反应产生了约40%的(Z)-2-烯酸酯和约60%的(E)-2-烯酸酯,平均产率为60%。与3-烷酮的反应则得到了56%的(Z)-2-烯酸酯和44%的(E)-2-烯酸酯。在14种(Z)-2-烯酸甲酯化合物中展示了警报信息素活性。研究表明,分子中存在(Z)-烯丙基初级醇酸甲酯基团是诱导信息素活性的关键,且不需要非环状单萜碳骨架。
Pheromone study on acarid mites. Part IX. Syntheses of alarm pheromone analogues of the mold mite, Tyrophagus putrescentiae, and their biological activities.
摘要:
针对霉菌螨(Tyrophagus putrescentiae),3, 7-二甲基-(Z)-2-辛烯酸甲酯(II)是除了天然信息素(奈尔酸甲酯 I)外,作为警报信息素最活跃的化合物,其活性与 I 相当(1-10ppm)。为了阐明诱导警报信息素活性的结构要求,制备了16个 I 的类似物,通过改造 II 的结构。为制备3-甲基和3-乙基-(Z)-2-烯酸甲酯,采用了乙氧基或甲氧基碳酰基甲烯三苯基膦与2-烷酮或3-烷酮的威蒂格反应。与2-烷酮的反应产生了约40%的(Z)-2-烯酸酯和约60%的(E)-2-烯酸酯,平均产率为60%。与3-烷酮的反应则得到了56%的(Z)-2-烯酸酯和44%的(E)-2-烯酸酯。在14种(Z)-2-烯酸甲酯化合物中展示了警报信息素活性。研究表明,分子中存在(Z)-烯丙基初级醇酸甲酯基团是诱导信息素活性的关键,且不需要非环状单萜碳骨架。
diallylic alcohols in acidic medium is disclosed, highlighting the difference between strong Lewis acid and mild Brønsted acid catalysis. In the presence of bismuth(III) triflate, allylicalcohol activation affords diversely substituted cyclopentenones in a Nazarov-type electrocyclization, whereas activation of the thioenol ether by p-toluenesulfonic acid provides an entry to α-sulfenylated β,γ-unsaturated
Synthetic Method to Form 2,2′-Bis(naphthoquinone) Compounds
作者:Vishwajeet Jha、Navneet Goyal、Cheryl K. Stevens、Edwin Stevens、Jayalakshmi Sridhar
DOI:10.1021/acs.joc.7b02501
日期:2017.12.15
We have discovered a transition-metal-free approach to the synthesis of 2,2′-bis(naphthoquinones) using a Diels–Alder reaction of conjugated ketene silyl acetals with benzoquinone. Its monomer analogue can also be synthesized by simply increasing the equivalents of benzoquinone.
A straightforward two-step entry to α-oxgenated β,γ-unsaturated ketones from readily available α,β-unsaturated ketones is disclosed. It was found that bis(allylic) alcohols undergo a skeletal rearrangement in the presence of 1 mol% of cheap and non-corrosive p-toluenesulfonic acid. Computational studies were conducted to support the mechanism and to rationalise the influence of the catalyst acidity
Enantioselectiveepoxidation of β,β-disubstituted enamides with aqueous hydrogen peroxide and a novel manganesecatalyst is described. Epoxidation is stereospecific and proceeds fast under mild conditions. Amides are disclosed as key functional groups to enable high enantioselectivity.