- Production process of high-purity and high-yield spirodiclofen
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The invention relates to the technical field of synthesis of compounds and specifically relates to a production process of high-purity and high-yield spirodiclofen. The production process comprises the following steps: performing an addition reaction on cyclohexanone which is taken as a starting material, so as to obtain 1-cyano-cyclohexanol; hydrolyzing and esterifying the 1-cyano-cyclohexanol, so as to obtain 1-hydroxylethyl formate; performing a condensation ring-closing reaction on the 1-hydroxylethyl formate, so as to obtain an intermediate caproate; and performing a reaction on the caproate and 2, 2-dimethylbutyryl chloride, so as to obtain the spirodiclofen. According to the production process, the problem in the prior art that the prepared spirodiclofen is low in purity and yield is solved; the spirodiclofen prepared by adopting the production process is high in purity and yield; and in addition, the raw material for preparing the spirodiclofen is easily obtained, and the operation is convenient.
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- Preparation method of spirodiclofen and intermediate of spirodiclofen
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The invention discloses a preparation method of spirodiclofen and an intermediate of spirodiclofen. The intermediate of spirodiclofen is 3-(2,4-dichlorophenyl)-2-oxo-1-oxaspiro[4,5]dec-3-ene-4-ol. Thepreparation method comprises the following steps: ethyl or methyl hydroxycyclohexanoate and 2,4-dichlorophenylacetic acid are esterified under the action of a dehydrating agent and then subjected tocyclization reaction, and 3-(2,4-dichlorophenyl)-2-oxo-1-oxaspiro[4,5]dec-3-ene-4-ol is generated. Compared with a traditional process, the synthesis process has the advantages of relatively short synthesis route, simple treatment process, greatly shortened production cycle, obviously increased total yield, reduced production cost and relatively reduced waste water and waste material emissions, and is environmentally friendly accordingly.
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Paragraph 0006; 0011; 0035-0037
(2018/12/13)
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- Spirodiclofen and spiromesifen - Novel acaricidal and insecticidal tetronic acid derivatives with a new mode of action
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The broad spectrum acaricides spirodiclofen (BAJ2740, trade name: Envidor) and spiromesifen (BSN2060, trade name: Oberon) with an additional excellent activity against whiteflies, both belong to the new chemical class of tetronic acid derivatives discovered at Bayer CropScience during the 1990s. The discovery process starting from herbicidal PPO (protoporphyrinogen oxidase) chemistry, the synthetic routes leading to the products, and some insight into process development of central intermediates is given. Spirodiclofen and spiromesifen have a new mode of action (interference with lipid biosynthesis), show no cross-resistance to any resistant mite or whitefly field population and are therefore valuable tools for resistance management.
- Bretschneider, Thomas,Benet-Buchholz, Jordi,Fischer, Reiner,Nauen, Ralf
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p. 697 - 701
(2007/10/03)
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- Cyclic Ether Formation in Superacid Media
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The formation of ethers in superacids by interaction of a primary hydroxy group with a carbocation centre has been investigated by a study of cyclisation of suitable substrates, mainly 1-(2-hydroxyethyl)cyclohexanols to give hydrobenzofurans.Cyclisation traps thermodynamically stable ionic species, with rates of reaction dependent upon the size of the ether ring formed.Three- and four-membered ether rings were not formed, five-membered ether rings formed readily, the reaction being comparable in rate with a 1,2-methyl shift.Six-membered rings formed a little less readily and seven-membered rings less readily still, though a yield of 34 percent from a suitable substrate has been recorded.An unexpected feature of the reactions was their stereospecificity; in one case, this is believed to result from a methyl shift concerted with attack of the primary hydroxy group, the reaction proceeding through hindered transition state, in which methyl loss, probably as CH3+, competes with a 1,2-methyl shift.
- Carr, Graham,Whittaker, David
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p. 359 - 366
(2007/10/02)
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