4489-14-9Relevant articles and documents
Practical method for crystalline-liquid resolution of chrysanthemic acids utilizing chiral 1,1′-binaphthol monoethyl ethers directed for process chemistry
Atago, Takayuki,Tanaka, Akihiro,Kawamura, Tomoyuki,Matsuo, Noritada,Tanabe, Yoo
, p. 1015 - 1019 (2009)
We have developed an efficient practical resolution method for (1R,3R)-trans-chrysanthemic acid 1 and (1R,3S)-trans-2,2-dimethyl-3-(2,2-dichloroethenyl)cyclopropanecarboxylic acid 2, based on the preliminary results of the simpler analogues, (1R)-2,2-dichlorocyclopropanecarboxylic acid 3 and (1R)-2,2-dimethylcyclopropanecarboxylic acid 4, using a crystalline-liquid separation procedure (without column chromatography) with chiral 1,1′-binaphthol monoethyl ethers (R)-5b as the key auxiliary. Direct esterifications of 1, 2, 3, and 4 with (R)-5b gave four sets of (1R)- and (1S)-diastereomeric esters 8, 9, 6, and 7, respectively, with markedly different melting points. All of these diastereomers were easily obtained using a simple and one-step crystalline-liquid separation. The separated diastereomers 8 and 9 were easily hydrolyzed to the desired enantiopure acids 1 (>98%) and 2 (>99%), respectively, with recovery of (R)-5b (>90%).
Synthesis and characterization of chrysanthemic acid esters
Ding, Qingwei,Li, Yonghong,Zhang, Mingang
experimental part, p. 2881 - 2883 (2012/08/29)
A short and convenient synthesis for a series of novel chrysanthemic acid esters from aldehyde and chrysanthemic acid is reported.
ALPHA-CYANO-4-FLUORO-3-PHENOXYBENZYL META-HALO PYRETHRATE, A PROCESS FOR PREPARING THE SAME AND THE USES THEREOF
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Page/Page column 3; 4, (2010/12/29)
The present invention relates to a compound of formula (I), stereoisomers thereof or the mixture of these stereoisomers, wherein: X represents a halogen atom, i.e. F, Cl, Br. The present invention also relates to a process for preparing the compound, and to a use of the compound in the preparation of an insecticide for controlling or killing vectors in the public hygiene and disease control, and to a use of the compound in the preparation of an insecticide for controlling or killing insects, nematodes, and mites in agriculture or horticulture.