Ansätze zur Synthese Trifluormethoxy‐substituierter Verbindungen

Abstract

Aufgrund der einzigartigen Eigenschaften der Trifluormethoxygruppe finden Moleküle, die diesen Baustein enthalten, in verschiedenen Bereichen Anwendung, besonders in den Biowissenschaften. Obwohl also an dieser funktionellen Gruppe ein großes Interesse besteht, ist gegenwärtig nur eine geringe Anzahl an trifluormethoxylierten Molekülen präparativ zugänglich. In den letzten Jahren sind mehrere innovative und vielversprechende Strategien für die Synthese von trifluormethoxylierten Verbindungen beschrieben worden. In diesem Kurzaufsatz werden diese Methoden diskutiert, mit einem Fokus auf aktuelleren Fortschritten.

Stable and Storable N(CF3)2 Transfer Reagents

“…[58] The bis(triphenylphosphane) complexes 1 b and 2 b were studied by diffusion-ordered spectroscopy (DOSY) in CD 3 CN and CD 2 Cl 2 (Table S7). The diffusion constants derived from the 1 H and 19 F NMR measurements on samples dissolved in CD 2 Cl 2 are very similar. The hydrodynamic radii of 1 b ( 1 H DOSY: 6.15 Å; 19 The novel thermally robust bis(trifluoromethyl)amido copper(I) and silver(I) complexes were used for the introduction of the N(CF 3 ) 2 group into organic molecules.…”

“…The diffusion constants derived from the 1 H and 19 F NMR measurements on samples dissolved in CD 2 Cl 2 are very similar. The hydrodynamic radii of 1 b ( 1 H DOSY: 6.15 Å; 19 The novel thermally robust bis(trifluoromethyl)amido copper(I) and silver(I) complexes were used for the introduction of the N(CF 3 ) 2 group into organic molecules. The reactions studied, so far, are i) nucleophilic substitutions giving a set of benzylbis (trifluoromethyl)amines (4À 6), 2-bis(trifluoromethyl) aminomethylnaphthalene ( 7), 2-bis(trifluoromethyl)amino acetate (8 a), and ii) a Sandmeyer reaction leading to 1-fluoro-4bis(trifluoromethyl)aminobenzene (9).…”

“…The further potential of the coinage metal(I) complexes as bis(trifluoromethyl)amination reagents was demonstrated by the conversion of 4-fluorobenzenediazonium tetrafluoroborate into 1-fluoro-4-bis(trifluoromethyl)aminobenzene ( 9) with [(bpy) Cu{N(CF 3 ) 2 }] (1 a) in 34 % yield as assessed by 19 F NMR spectroscopy (Scheme 1). An analogous Sandmeyer reaction resulting in 9 was reported in the literature [40] starting from the corresponding 4-fluorobenzenediazonium bis(trifluoromethyl) amide and a copper(I) salt with a yield of 43 %.…”

“…Because of their easy accessibility using silver(I) fluoride and the respective perfluoroalkene, for example, heptafluoropropene and tetrafluoroethylene, [15] they are of increasing interest. Similarly, copper(I) and silver(I) complexes with perfluorinated ligands that are coordinated via oxygen, sulfur, or selenium to the coinage metal have recently come into focus and have been established as transfer reagents for perfluorinated groups, for example for trifluoromethoxylation,[ 19 , 20 ] trifluoromethylthiolation,[ 21 , 22 ] and trifluoromethylselenolation reactions. [ 23 , 24 ] So far, only few Cu I and Ag I metal complexes with the trifluoromethoxy ligand like [(Ph t Bu 2 P)(bpy)AgOCF 3 ] [25] are known (Figure 1 ).…”

Electrophilic trifluoromethylselenolation of terminal alkynes with Se-(trifluoromethyl) 4-methylbenzenesulfonoselenoate

“…In the objective to design new molecules with specific properties, novel fluorinated substituents have been developed, such as diverse trifluoromethylchalcogeno groups, due to their particular electronic properties [ 16 ] and, more especially, to their high lipophilicity [ 17 ]. Whereas the CF 3 O and CF 3 S substituents have been largely studied [ 18 – 23 ], the CF 3 Se group, albeit known, has gained only little attention until recently. However, selenylated derivatives present pertinent properties and have found some interest in materials [ 24 ], life sciences [ 25 – 33 ] and drug design [ 34 – 37 ].…”