Anilide ortho‐Arylation by Using CH Activation Methodology

“Greening Up” Cross-Coupling Chemistry

“…Importantly, under such mild conditions, monoarylated products could be obtained for substrate types that previously led to uncontrolled double arylation [22], such as a simple unsubstituted phenyl urea. As has been previously observed [22,23], contrary to the normal aryl halide cross-coupling reactivity profile, electron-rich aryl iodides were typically more reactive than their electron-deficient counterparts. Especially challenging substrates, including those bearing strongly electronwithdrawing groups and ortho-substituted iodides are currently still outside the scope of this methodology.…”

“…Extensive pioneering work, where halides serve as partners in direct C-H arylation of anilide derivatives, has been reported by the Sanford [21] and Daugulis [22,23] groups. To realize products of couplings for this transformation, however, temperatures at or around 130°C are common, along with strong protic acid such as TFA as solvent.…”

“…To realize products of couplings for this transformation, however, temperatures at or around 130°C are common, along with strong protic acid such as TFA as solvent. Moreover, under such conditions, substrates are oftentimes prone to double ortho-arylation [23].…”

Diaryliodonium Salts in Organic Syntheses: A Useful Compound Class for Novel Arylation Strategies

“…The synthesis of benzoxazine derivatives was also achieved in our laboratory by utilization of copper on iron catalyst 72 used previously in our group for the construction of pyrazole derivatives. 73 In 2015, the methodology was extended on aromatic nitriles (94) equipped with amido function in ortho position for the synthesis of imino-benzoxazine 74 derivatives (95). With this reaction we demonstrated that the carbon-nitrogen triple bond can also be activated similarly to carbon-carbon triple bond.…”

“…reported an example of anilide ortho-arylation using the C-H activation methodology (Scheme 52). 95 The reaction of 4-methylpivalanilide (122) with excess diphenyliodonium tetrafluoroborate (123) underwent smoothly in presence of 5 mol% palladium(II) acetate catalyst and gave interestingly the sterically crowded 2,6-diarylated product (124) in 79% isolated yield.…”