27205-24-9Relevant academic research and scientific papers
Cyclohexyl clethodim synthesis process
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Paragraph 0010-0017, (2020/01/12)
The invention relates to a cyclohexyl clethodim synthesis process, which comprises: (1) preparing 3-ethylthiobutyraldehyde by using ethanethiol and crotonaldehyde as raw materials; 2) carrying out a reaction on the 3-ethylthiobutyraldehyde and sodium acetoacetate by using secondary amine as a catalyst to prepare 6-ethylthio-3-heptene-2-one; 3) carrying out addition cyclization on the 6-ethylthio-3-heptene-2-one and diethyl malonate, and carrying out hydrolysis decarboxylation to obtain 5-(2-ethylthiopropyl)cyclohexane-1,3-dione; 4) carrying out O-acylation on the 5-(2-ethylthiopropyl)cyclohexane-1,3-dione through propionyl chloride, and carrying out rearrangement to obtain acylated 5-(2-ethylthiopropyl)-2-propionyl-3-hydroxy-2-cyclohexene-1-one; and 5) carrying out a reaction on the 5-(2-ethylthiopropyl)-2-propionyl-3-hydroxy-2-cyclohexene-1-one and 3-chloro-2-propenyl amine hydrochloride to prepare clethodim. According to the invention, the clethodim crude oil with a content of largerthan 97% is obtained by using ethanethiol and crotonaldehyde as the raw materials through the five-step reaction, wherein the total yield is larger than 62%, and the two-step yield of the intermediate 3-chloro-2-propenyl hydroxylamine is larger than 92%; and the method can be used for industrial production and has a good market prospect.
Rhodium-catalysed intermolecular alkyne hydroacylation: The enantioselective synthesis of α- and β-substituted ketones by kinetic resolution
Gonzalez-Rodriguez, Carlos,Parsons, Scott R.,Thompson, Amber L.,Willis, Michael C.
supporting information; experimental part, p. 10950 - 10954 (2010/11/05)
Chemical Equation Presented Cleared up! Intermolecular alkyne hydroacylation represents a new addition to the range of transition- metalcatalysed hydroacylation reactions that can be performed in an enantioselective manner. By using a kinetic resolution procedure, both racemic α- and βsubstituted aldehydes can be converted into the corresponding enantiomerically enriched substituted enone products (see scheme).
NOVEL HERBICIDES
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Page/Page column 39, (2008/12/07)
Cyclohexanedione compounds, and derivatives thereof, which are substituted in 5-position, are suitable for use as herbicides.
Rhodium-catalyzed intermolecular chelation controlled alkene and alkyne hydroacylation: Synthetic scope of β-S-substituted aldehyde substrates
Willis, Michael C.,Randell-Sly, Helen E.,Woodward, Robert L.,McNally, Steven J.,Currie, Gordon S.
, p. 5291 - 5297 (2007/10/03)
The use of β-S-substituted aldehydes in rhodium-catalyzed intermolecular hydroacylation reactions is reported. Aldehydes substituted with either sulfide or thioacetal groups undergo efficient hydroacylation with a variety of electron-poor alkenes, such as enoates, in Stetter-like processes and with both electron-poor and neutral alkynes. In general, the reactions with electron-poor alkenes demonstrate good selectivity for the linear regioisomer, and the reactions with alkynes provide enone products with excellent selectivity for the E-isomers. The scope of the process was shown to be broad, tolerating a variety of substitution patterns and functional groups on both reaction components. A novel CN-directing effect was shown to be responsible for reversing the regioselectivity in a number of alkyne hydroacylation reactions. Catalyst loadings as low as 0.1 mol % were achievable.
Rhodium-catalyzed reductive aldol reactions using aldehydes as the stoichiometric reductants
Willis, Michael C.,Woodward, Robert L.
, p. 18012 - 18013 (2007/10/03)
Chelated acyl rhodium hydrides, generated from the addition of [Rh(dppe)]ClO4 to β-sulfide-substituted aldehydes, can function as the stoichiometric reductants in reductive aldol processes. Unsaturated nitriles, esters, and ketones can be used as enolate equivalents, and a variety of simple α- and β-substituted aldehydes can be employed. The use of a second, more electrophilic, aldehyde allows three-component reactions to be performed. Copyright
