Palladium‐Catalyzed Regioselective Cross‐Dehydrogenative Coupling of Benzofurans with Uracils at Room Temperature

Abstract

The Pd‐catalyzed cross‐dehydrogenative coupling (CDC) between two heteroarenes was developed. A variety of benzofuran and uracil derivatives were constructed through C–C bond formation by using CDC reactions. The substrates did not require prefunctionalization, and the products were obtained in good yields with good regioselectivities at room temperature.

Palladium-Catalyzed Weakly Coordinating Lactone-Directed C–H Bond Functionalization of 3-Arylcoumarins: Synthesis of Bioactive Coumestan Derivatives

“…Finally, double reductive elimination from intermediate C provides trifluoroacetate intermediate D , which upon hydrolysis gets converted into a hydroxylated coumarin 5 . In the case of ortho -alkenylation, the reaction possibly proceeds through oxidative Heck reaction from intermediate A or B …”

Transition metal-catalyzed coupling of heterocyclic alkenesviaC–H functionalization: recent trends and applications

“…The dehydrogenative coupling with benzofurans is successful using PivOH at room temperature (Scheme 15). 28 The scope of the procedure is somewhat limited, and the mechanism involves an electrophilic palladation, while the C6-arylation employing aryl halides and boronic acids is effective at 110°C (Scheme 16). 29 The combination of Pd(OAc) 2 , CuI, xantphos and DBU is essential.…”

A Visible‐Light‐Promoted C‐H Arylation and Heteroarylation of Uracil Derivatives with Diazoniums in Aqueous Conditions

“…By using this typical method, the 5‐labeled elagolix can be easily synthesized from 5‐iodouracil (Soli, Surber, & Reed, 2021). Third, in order to reduce the pre‐functionalization step, transition‐metal‐catalyzed C‐H arylations or heteroarylations of uracil and its analogues have also been developed (Čerňová, Čerňa, Pohl, & Hocek, 2011; Čerňová, Pohl, & Hocek, 2009; Cresswell, & Lloyd‐Jones, 2016; Kianmehr et al., 2015; Kianmehr, Rezaeefard, Khalkhalia, & Khanb, 2014; Kianmehr, Torabi, Khalkhali, Faghih, & Khan, 2015; Kim, Lee, & Kim, 2011). All of these methodologies have been successfully utilized in the efficient synthesis of numerous bioactive uracil molecules (Gayakhe, Sanghvi, Fairlamb, & Kapdi, 2015; Hassan, 1985).…”