261635-83-0Relevant academic research and scientific papers
PROCESS FOR THE PREPARATION OF 6-(HALOALKYL)-2-HALO-5-ACYLPYRIDINES AND INTERMEDIATES FOR THIS PROCESS
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, (2020/02/23)
The present invention relates to a process for preparing compounds of formula (I) (I), wherein R represents C1-C2-alkyl or C1-C2-haloalkyl, R1 represents C1-C6-alkyl, C2-C6-alkenyl, C2-C6- alkynyl, C3-C8-cycloalkyl, C3-C8-cycloalkyl-C1-C4-alkyl, phenyl, phenyl-C1-C4-alkyl, phenyl-C2-C4- alkenyl or phenyl-C2-C4-alkynyl, and X represents chlorine or bromine, by reacting a compound of formula (II) (II), wherein RA represents -CN or –COOH and R is defined as in formula (I), in a first step A) with a dehydroxyhalogenation agent selected from COCl2, diphosgene, triphosgene, cyanuric chloride, SOCl2, SO2Cl2, PCl3, PCl5, POCl3, PBr3, SOBr2 and SO2Br2, to arrive at a compound of formula (III) (III), wherein RB represents -CN or –COX, and X and R are defined as in formula (I), and the compound of formula (III) is reacted in step B) with a compound of formula (IV) R1M1(lV), - 41 - wherein M1 represents Li or MgY, wherein Y represents chlorine or bromine, and R1 is defined as in formula (I), and optionally further reacting the compound of formula (I) to a triazole derivative of formula (VIII) (VIII). It further relates to a process for preparing the compound of formula (II) and to particular compounds of formula (II) and (III).
Three chloro(trifluoromethyl)pyridines as model substrates for regioexhaustive functionalization
Cottet, Fabrice,Schlosser, Manfred
, p. 3793 - 3798 (2007/10/03)
As a further test of the concept of regioexhaustive functionalization, 2-chloro-6-(trifluoromethyl)pyridine, 2-chloro-5-(trifluoromethyl)pyridine and 3-chloro-4-(trifluoromethyl)-pyridine were each converted into the three possible carboxylic acids 2, 4, 6, 8, 10, 12, 16, 17 and 20. This was achieved by employing several, but not all of the organometallic "tool-box methods": transformation of a more basic organometallic species into a less basic isomer by transmetalation-equilibration, site discriminating deprotonation with lithium N,N-diisopropylamide or lithium 2,2,6,6- tetramethylpiperidide, regio-divergent iodine migration and steric screening of acidic positions by a bulky trialkylsilyl group. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
Pyridine ketones useful as herbicides
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, (2008/06/13)
Compounds of formula (I) in which the substituents are as defined in claim 1 are suitable for use as herbicides.
