Metal-free C–H mercaptalization of benzothiazoles and benzoxazoles using 1,3-propanedithiol as thiol source
- Yan Xiao,
- Bing Jing,
- Xiaoxia Liu,
- Hongyu Xue and
- Yajun Liu
Beilstein J. Org. Chem. 2019, 15, 279–284, doi:10.3762/bjoc.15.24
Graphical Abstract
Figure 1: Representative examples of biologically active 2-mercaptobenzoxazoles and 2-mercaptobenzothiazoles.
Scheme 1: Strategies for the synthesis of 2-mercaptobenzothiazole and 2-mercaptobenzoxazole (X = O, S).
Figure 2: Substrate scope of the developed C–H mercaptalization strategy. Reaction conditions: benzothiazole ...
Scheme 2: Control experiments.
Scheme 3: Proposed reaction pathway.
Transition-metal-catalyzed synthesis of phenols and aryl thiols
- Yajun Liu,
- Shasha Liu and
- Yan Xiao
Beilstein J. Org. Chem. 2017, 13, 589–611, doi:10.3762/bjoc.13.58
Graphical Abstract
Figure 1: Examples of drugs bearing phenol or aryl thiol as central structural motifs.
Scheme 1: Hydroxylation of aryl halides using biphenylphosphine as ligand.
Scheme 2: Hydroxylation of aryl halides using tert-butylphosphine as ligand.
Scheme 3: Hydroxylation of aryl halides using imidazole typed phosphine ligands.
Scheme 4: [Pd(cod)(CH2SiMe3)2] catalyzed hydroxylation of aryl halides.
Scheme 5: Pd/PANI catalyzed hydroxylation of hydroxylation of aryl halides.
Scheme 6: MCM-41-dzt-Pd catalyzed hydroxylation of aryl halides.
Scheme 7: Hydroxylation of aryl halides using dibenzoylmethane as ligand.
Scheme 8: Hydroxylation of aryl halides using 2,2’-bipyridine as ligand.
Scheme 9: Hydroxylation of aryl bromides using imidazolyl pyridine as ligand.
Scheme 10: Hydroxylation of aryl halides using DMEDA as ligand.
Scheme 11: Hydroxylation of aryl halides using PAO as ligand.
Scheme 12: Hydroxylation of aryl halides using D-glucose as ligand.
Scheme 13: Hydroxylation of aryl halides using INDION-770 as ligand.
Scheme 14: PEG-400 mediated hydroxylation of aryl halides.
Scheme 15: Hydroxylation of aryl halides using glycolic acid as ligand.
Scheme 16: Hydroxylation of aryl halides using L-sodium ascorbate as ligand.
Scheme 17: Difunctionalized ethanes mediated hydroxylation of aryl iodides.
Scheme 18: Hydroxylation of aryl halides using 2-methyl-8-hydroxylquinoline as ligand.
Scheme 19: Hydroxylation of aryl halides using 8-hydroxyquinolin-N-oxide as ligand.
Scheme 20: Hydroxylation of aryl halides using lithium pipecolinate as ligand.
Scheme 21: Hydroxylation of aryl halides using L-lithium prolinate.
Scheme 22: Hydroxylation of aryl halides using triethanolamine as ligand.
Scheme 23: CuI-nanoparticle-catalyzed hydroxylation of aryl halides.
Scheme 24: Cu-g-C3N4-catalyzed hydroxylation of aryl bromides.
Scheme 25: Cu(OAc)2-mediated hydroxylation of (2-pyridyl)arenes.
Scheme 26: Removable pyridine moiety directed hydroxylation of arenes.
Scheme 27: Removable quinoline moiety directed hydroxylation of arenes.
Scheme 28: CuCl2 catalyzed hydroxylation of benzimidazoles and benzoxazoles.
Scheme 29: Disulfide-directed C–H hydroxylation.
Scheme 30: Pd(OAc)2-catalyzed hydroxylation of diarylpyridines.
Scheme 31: PdCl2-catalyzed hydroxylation of 2-arylpyridines.
Scheme 32: PdCl2-catalyzed hydroxylation of 2-arylpyridines.
Scheme 33: Pd(OAc)2-catalyzed hydroxylation of 2-arylpyridines.
Scheme 34: Pd(CH3CN)2Cl2-catalyzed hydroxylation of 2-arylpyridines.
Scheme 35: Pd(OAc)2-catalyzed hydroxylation of benzothiazolylarenes.
Scheme 36: Pd(OAc)2 catalyzed hydroxylation of benzimidazolylarenes.
Scheme 37: Dioxane mediated hydroxylation of 2-heteroarylarenes.
Scheme 38: Hydroxylation of oxime methyl ester.
Scheme 39: CN-directed meta-hydroxylation.
Scheme 40: Pd(OAc)2-catalyzed hydroxylation of benzoic acids.
Scheme 41: Pd(OAc)2-catalyzed hydroxylation of biaryl or aryl alkyl ketones.
Scheme 42: Pd(OAc)2 and Pd(TFA)2 catalyzed hydroxylation of aryl ketones.
Scheme 43: Pd(OAc)2 catalyzed hydroxylation of aryl ketones.
Scheme 44: Pd(TFA)2-catalyzed hydroxylation of aryl phosphonates.
Scheme 45: Hydroxy group directed hydroxylation.
Scheme 46: [Ru(O2CMes)2(p-cymene)] catalyzed hydroxylation of benzamides and aryl ketones.
Scheme 47: [RuCl2(p-cymene)]2-catalyzed hydroxylation of benzamides and carbamates.
Scheme 48: [RuCl2(p-cymene)]2 catalyzed hydroxylation of benzaldehydes.
Scheme 49: [RuCl2(p-cymene)]2 catalyzed hydroxylation of ethyl benzoates, benzamides and carbamates.
Scheme 50: Different regioselective ortho-hydroxylation.
Scheme 51: Ruthenium-complex-catalyzed hydroxylation of flavones.
Scheme 52: Vanadium-catalyzed hydroxylation of arenes.
Scheme 53: VOSiW-catalyzed hydroxylation of arenes.
Scheme 54: Synthesis of aryl thiols using thiourea as thiol source.
Scheme 55: Synthesis of aryl thiols using alkyl thiol as thiol source.
Scheme 56: Synthesis of 1-thionaphthol using HS-TIPS as thiol source.
Scheme 57: Synthesis of aryl thiols using sodium thiosulfate as thiol source.
Scheme 58: Synthesis of thiophenol using thiobenzoic acid as thiol source.
Scheme 59: Synthesis of aryl thiols using sulfur powder as thiol source.
Scheme 60: CuI-nanoparticles catalyzed synthesis of aryl thiols.
Scheme 61: Synthesis of aryl thiols using Na2S·5H2O as thiol source.
Scheme 62: Synthesis of aryl thiols using 1,2-ethanedithiol as thiol source.
