Perfluorinated Nonaromatic Heterocycles

Facile In Situ Difluoromethylation of Phenols and Thiols Using Ethyl Bromodifluoroacetate and K2CO3

“…Fluorine is widely considered as an important element in pharmaceutical and agrochemical industry. 1 2 Fluorination can have a significant effect on a compound’s potency, lipophilicity, p K a , as well as membrane permeability. 3–10 The introduction of a difluoromethyl group onto aromatic and heterocyclic rings has received less attention than trifluoromethylation, perhaps due to scarce available synthetic methods.…”

Synthesis of 2-trifluoromethyl benzimidazoles, benzoxazoles, and benzothiazoles via condensation of diamines or amino(thio)phenols with CF3CN

“…In this regard, several synthetic methods have been introduced in the past decade for the construction of 2-trifluoromethyl benzimidazoles, 14–21 because the introduction of a trifluoromethyl group can improve physicochemical properties, metabolic stability, and binding potency. 22–26 Among the strategies developed, Phillips condensation with o -arylenediamine and trifluoroacetic acid was most commonly used to access 2-(trifluoromethyl)benzimidazoles (Scheme 1a). 27,28 Some of these approaches necessitate the use of reagents or starting materials that are either expensive or require multiple steps for their synthesis, and the reactions are performed under strongly acidic conditions, thereby limiting their synthetic versatility.…”

Straightforward Synthesis of Halopyridine Aldehydes via Diaminomethylation

“…Several approaches have been developed for the synthesis of fluoro‐containing pyridines with commercial availability on the market. However, their subsequent modification often requires complex multi‐step syntheses [6,7] . A convenient and cost‐effective approach selectively modifying readily available polyfluorinated compounds at C−H bonds would be a practical approach.…”

“…However, their subsequent modification often requires complex multistep syntheses. [6,7] A convenient and cost-effective approach selectively modifying readily available polyfluorinated com-pounds at CÀ H bonds would be a practical approach. Although CÀ H bond functionalization of pyridines offers a rapid and atom-economic transformation, particularly advantageous for late-stage functionalization, [8] it presents challenges and often requires expensive catalysts.…”