Nucleophilic Trifluoromethylation of C=N Bonds

Abstract

The review covers nucleophilic addition reactions of the CF 3 carbanion to C=N bonds. Trifluoromethylation reactions of imines, nitrones, hydrazones, iminium ions and azomethine

Palladium-Mediated Organofluorine Chemistry

“…8,57 ,58 Trifluoromethyltriethylsilane is commercially available, it is increasingly used and its applications have been reviewed. 4,58,59 The reagent requires the use of a nucleophile (typically F -) to activate the CF 3 -Si bond. The CF 3 -that is generated readily decomposes to difluorocarbene (F 2 C:) and fluoride (F -), so the reaction rate of the reaction of this anion with the final reagent (the palladium complex) has to be high enough to avoid its accumulation in solution and its eventual decomposition.…”

Nucleophilic trifluoromethylation of carbonyl compounds and derivatives

“…60 As it happens with carbonyl compounds (see previous sections), the most used reagent towards this end is the Ruppert-Prakash 1 (RPr) which can be activated in different ways (Scheme 37).…”

“…60 The list includes the addition product of N,N-dimethyltrimethylsilylamine with 2,2,2-trifluoroacetophenone 95, the reagent 96 derived from CF 3 I and tetrakis(dimethylamino)ethylene (TDAE) and potassium trimethoxy(trifluoromethyl)borate 25 ( Figure 2). …”

4-Trifluoromethyl-p-quinols as dielectrophiles: three-component, double nucleophilic addition/aromatization reactions

“…In the last decade, the introduction of fluorine-containing groups1234567891011121314151617181920212223 into organic molecules has become a major research focus. Trifluoromethyl containing motifs in an aromatic system are common pharmacophores (Fig.…”

“…Due to the high electronegativity of fluorine, the nucleophilic CF 3 species are considered as hard nucleophiles, which usually undergo 1,2-addition reactions with α,β-unsaturated carbonyl compounds16171819203132, including divinyl ketones20 and p -quinones313233. In 1989, Stahly and Bell described the monotrifluoromethylation of p -quinones with Et 3 SiCF 3 and the further transformation to otherwise hardly accessible (trifluoromethyl)phenols by treatment of the adducts, 4-(trifluoromethyl)- p -quinol silyl ethers, (or the corresponding alcohols, 4-(trifluoromethyl)- p -quinols) by dissolving metal reduction (Fig.…”