CuI-catalyzed hydroxylation of aryl bromides under the assistance of 5-bromo-2-(1H-imidazol-2-yl)pyridine and related ligands

Picolinamides as Effective Ligands for Copper‐Catalysed Aryl Ether Formation: Structure–Activity Relationships, Substrate Scope and Mechanistic Investigations

“…It is interesting to note that a trend is recognisable in the activity of differently substituted ligands. For ligands substituted in the ortho position ( L27 – L30 ), the activity decreased from fluorine to iodine; this trend may be due to the possibility of intramolecular coupling within the ligand, which has been previously observed 48. 49 The decrease in yield when using ortho ‐brominated ligands L41 and L44 , in comparison with L33 and L37 ( meta ‐ and para ‐substituted), may be due to the same reason.…”

“…For ligands substituted in the ortho position (L27-L30), the activity decreased from fluorine to iodine; this trend may be due to the possibility of intramolecular coupling within the ligand, which has been previously observed. [48,49] The decrease in yield when using ortho-brominated ligands L41 and L44, in comparison with L33 and L37 (meta-and para-substituted), may be due to the same reason. The yield decreases from ortho-to para-substituted ligands with fluorine, but increases again when a second fluorine atom is inserted in the ortho position (L39 and L42), which confirms the importance of the ortho fluorine atom.…”

The Constituents of Roots and Stems of Illigera luzonensis and Their Anti-Platelet Aggregation Effects

“…Each layer was subjected into purification by a combination of conventional chromatographic techniques to result in four new compounds ( 1 – 4 ). In addition, 27 known compounds were identified to be methyl ferulate ( 5 ) [ 10 ], (6-methoxy-9 H -β-carbolin-1-yl)-(4-methoxy-phenyl)-methanone ( 6 ) [ 11 ], cathafiline ( 7 ) [ 12 ], methyl p -hydroxycinnamate ( 8 ) [ 13 ], 2-(4'-hydroxyphenyl)-ethyl tricosanoate ( 9 ) [ 14 ], machigline ( 10 ) [ 15 ], launobine ( 11 ) [ 7 ], actinodaphnine ( 12 ) [ 16 ], ferulic acid ( 13 ) [ 17 ], (+)- N -methoxycarbonyl-lindcarpine [ 18 ], caaverine [ 19 ], noroliveroline [ 20 ], pallidine [ 21 ], thalifoline [ 22 ], nicotinic acid [ 22 ], p -hydroxybenzaldehyde [ 23 ], p -hydroxybenzoic acid [ 24 ], methylparaben [ 25 ], vanillin [ 26 ], vanillic acid [ 27 ], methyl vanillate [ 22 ], methyl caffeate [ 28 ], methyl syringate [ 29 ], p -hydroxybenzyl methyl ether [ 30 ], squalene [ 31 ], β-sitosterol [ 32 ], and allantoin [ 33 ] by comparison of their physical and spectral data with those reported in the literature.…”

Transition-metal-catalyzed synthesis of phenols and aryl thiols

“…In 2011, the Zhang and Ma group screened a series of 2-heteroarylpyridines and found another N , N -bidentate ligand, 5-bromo-2-(1 H -imidazol-2-yl)pyridine ( L6 ), and succeeded to synthesize phenols from aryl bromides in the presence of CuI as catalyst in the mixed solvent of t -BuOH–DMSO–H 2 O at 120 °C (Scheme 9) [31]. Both electron-rich and electron-deficient aryl bromides were converted to the corresponding phenols in good to excellent yields.…”