Synthesis of functionalized m-bistrifluoromethylbenzenes via cyclocondensation of 1,1,1,5,5,5-hexafluoroacetylacetone with enamines
摘要:
The reaction of 1,1,1,5,5,5-hexafluoroacetylacetone with push-pull enamines having a methyl group at the alpha-position was investigated. It was found that the reaction is sensitive both to the structure of enamines and to reaction conditions. As a result, a set of bistrifluoromethyldialkylanilines and ethyl bistrifluoromethylsalicylate was prepared. Plausible mechanisms and factors influencing the course of the reaction are discussed. (c) 2005 Elsevier Ltd. All rights reserved.
Mannich products have been isolated in good yields with methylene chloride as a C1 unit, instead of formaldehyde. It is evidenced that, contrary to previous understanding, a high pressure procedure is not necessary required and that the methylene bisamines function as intermediates.
Souquet Florence, Martens Thierry, Fleury Maurice-Bernard, Synth Commun., 23 (1993) N 6, S 817-828