175205-81-9Relevant articles and documents
Method For Producing Substituted Halopyridines
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Page/Page column 4, (2008/12/08)
Methods for producing substituted halopyridines (II) by reacting a β-hydroxy-y-acyl butyronitrile (I) or a suitable acyl-protected derivative with hydrogen halides, or substances or mixtures that can release hydrogen halides. In the formulae (I) and (II): R, R4 represent H, a linear or branched alkyl group, optionally a substituted aryl group, an aralkyl group, or optionally a substituted heteroaryl group; R1, R2, R3 represent H, a linear or branched alkyl group, optionally a substituted aryl, aralkyl, optionally a substituted heteroaryl group or one of the following groups CnH(2n+1?m)Xm, COOR, or CN; R5 represents H, a linear or branched alkyl group, optionally a substituted aryl group, an aralkyl, optionally a substituted heteroaryl or one of the following groups CnH(2n+1?m)Xm, COOR, CN, SO2R, SOR, PO(OR)2; n represents a positive whole number; m represents a positive whole number ≦2n+1; and X represents F, Cl, Br, or I.
Recommendable routes to trifluoromethyl-substituted pyridine- and quinolinecarboxylic acids
Cottet, Fabrice,Marull, Marc,Lefebvre, Olivier,Schlosser, Manfred
, p. 1559 - 1568 (2007/10/03)
As part of a case study, rational strategies for the preparation of all ten 2-, 3-, or 4-pyridinecarboxylic acids and all nine 2-, 3-, 4-, or 8-quinolinecarboxylic acids bearing trifluoromethyl substituents at the 2-, 3-, or 4-position were elaborated. The trifluoromethyl group, if not already present in the precursor, was introduced either by the deoxygenative fluorination of suitable carboxylic acids with sulfur tetrafluoride or by the displacement of ring-bound bromine or iodine by trifluoromethylcopper generated in situ. The carboxy function was produced by treatment of organolithium or organomagnesium intermediates, products of halogen/metal or hydrogen/ metal permutation, with carbon dioxide. ( Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003).
