- Ligand compound for copper catalyzed aryl halide coupling reaction, catalytic system and coupling reaction
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The invention provides a ligand compound capable of being used for copper catalyzed aryl halide coupling reaction, the ligand compound is a three-class compound containing a 2-(substituted or non-substituted) aminopyridine nitrogen-oxygen group, and the invention also provides a catalytic system for the aryl halide coupling reaction. Thecatalytic system comprises a copper catalyst, a compound containing a 2-(substituted or non-substituted) aminopyridine nitrogen-oxygen group adopted as a ligand, alkali and a solvent, and meanwhile, the invention also provides a system for the aryl halide coupling reaction adopting the catalyst system. The compound containing the 2-(substituted or non-substituted) aminopyridine nitrogen oxygen group can be used as the ligand for the copper catalyzed aryl chloride coupling reaction, and the ligand is stable under a strong alkaline condition and can well maintain catalytic activity when being used for the copper-catalyzed aryl chloride coupling reaction. In addition, the copper catalyst adopting the compound as the ligand can particularly effectively promote coupling of copper catalyzed aryl chloride and various nucleophilic reagents which are difficult to generate under conventional conditions, C-N, C-O and C-S bonds are generated, and numerous useful small molecule compounds are synthesized. Therefore, the aryl halide coupling reaction has a very good large-scale application prospect by adopting the copper catalysis system of the ligand.
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Paragraph 0152-0159
(2021/05/29)
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- Chemoselective Demethylation of Methoxypyridine
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A chemoselective demethylation method for various methoxypyridine derivatives has been developed. Treatment of 4-methoxypyridine with L-selectride in THF for 2 h at reflux temperature afforded 4-hydroxypyridine in good yield; no reaction to anisole occurred. The utility of our method was demonstrated by the efficient synthesis of the metabolic substances of the antiulcer agent omeprazole. Chemoselective demethylation at the site of 3,5-dimethyl-4-methoxypyridine in the presence of 4-methoxybenzimidazole was achieved.
- Makino, Kosho,Hasegawa, Yumi,Inoue, Takahide,Araki, Koji,Tabata, Hidetsugu,Oshitari, Tetsuta,Ito, Kiyomi,Natsugari, Hideaki,Takahashi, Hideyo
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p. 951 - 954
(2019/05/10)
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- Rhodium-catalyzed synthesis of 1,2-dihydropyridine by a tandem reaction of 4-(1-acetoxyallyl)-1-sulfonyl-1,2,3-triazole
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A tandem reaction of 4-(1-acetoxyallyl)-1-sulfonyl-1,2,3-triazole including formation of α-imino rhodium carbene, 1,2-migration of an acetoxy group and six electron electrocyclic ring closure was reported. The migration of the OAc group with excellent chemoselectivity was the crucial process, leading to the formation of 1,2-dihydropyridine specifically in up to 90% yield. Several transformations of the dihydropyridine product were also achieved illustrating the potential of the protocol in organic synthesis. Based on the observation of the intermediate, a plausible mechanism was proposed.
- Dai, Haican,Yu, Sisi,Cheng, Wanli,Xu, Ze-Feng,Li, Chuan-Ying
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supporting information
p. 6417 - 6420
(2017/07/10)
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- Triethanolamine as an inexpensive and efficient ligand for copper-catalyzed hydroxylation of aryl halides in water
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The CuI/triethanolamine catalyst system efficiently promotes the direct hydroxylation of aryl iodides and bromides in water to provide the corresponding phenols in good to excellent yields. Moreover, the procedure avoids the use of toxic organic solvents and tolerates many functional groups. The CuI/triethanolamine catalyst system efficiently promotes the direct hydroxylation of aryl iodides and bromides in water to afford the corresponding phenols in good to excellent yields. Copyright
- Wang, Deping,Kuang, Daizhi,Zhang, Fuxing,Tang, Siping,Jiang, Wujiu
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supporting information
p. 315 - 318
(2014/01/23)
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- Triethanolamine as an Inexpensive and Efficient Ligand for Copper-Catalyzed Hydroxylation of Aryl Halides in Water
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The CuI/triethanolamine catalyst system efficiently promotes the direct hydroxylation of aryl iodides and bromides in water to provide the corresponding phenols in good to excellent yields. Moreover, the procedure avoids the use of toxic organic solvents and tolerates many functional groups.
- Wang, Deping,Kuang, Daizhi,Zhang, Fuxing,Tang, Siping,Jiang, Wujiu
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supporting information
p. 315 - 318
(2015/10/05)
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- 1,1- and 1,2-disubstituted cyclopropane compounds
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A compound selected from those of formula (I): wherein: p represents an integer of from 0 to 6 inclusive, n represents an integer of from 0 to 6 inclusive, R1, and R2 represent a group selected from hydrogen, alkyl, aryl and arylalkyl, or R1+R2 form together with nitrogen carrying them saturated, monocyclic, or bicyclic system, X represents a group selected from oxygen, sulphur, a group —CH═CH—, methylene, a group of formula —HC═N—O— and a group of formula —O—CH2—CH═CH—, in which groups oxygen is linked to Y of the compounds of formula (I), Y represents a group selected from aryl, heteroaryl, arylalkyl, heteroarylalkyl, —C(O)—A, and —C(S)—A, A represents a group selected from alkyl, aryl, heteroaryl, arylalkyl, heteroarylalkyl, and NR3R4 wherein R3, and R4 represent a group selected from hydrogen, alkyl, aryl, and arylalkyl, or R3+R4 form together with nitrogen carrying them monocyclic, or bicyclic (C3-C10) system, its isomers and addition salts thereof with a pharmaceutically-acceptable acid or base, and medicinal products containing the same are useful as specific nicotinic ligand of (α4β2 receptors.
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- Coumarins with imidazolyl group or pyridyloxy group having plateletes aggregation inhibiting activity
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Novel coumarin compounds of the formula STR1 wherein R1 represents an imidazolyl group or a pyridyloxy group which may be substituted by lower alkyl group(s); R2 represents a hydrogen atom or a lower alkyl group; and m represents an integer of 1 to 6; and the salts thereof, which inhibit platelets aggregation.
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- On the Formation of 2-Acylpyrroles and 3-Pyridinols in the Maillard Reaction through Strecker Degradation
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The effects of pH, reactant ratio and reaction time on the yields of 5-methylpyrrole-2-carboxaldehyde (6), 6-methyl-3-pyridinol (7), methyl 2-pyrrolyl ketone (8) and 2-methyl-3-pyridinol (9) in the reaction of D-glucose with glycine at 100 deg C in aqueous solution have been studied.THe use of -D-glucose showed that the methyl group in each of 6-9 is derived from C-6 of the glucose.The formation of 6-9 from some potential intermediates in the glucose-glycine reaction has also been investigated.The results support the previously proposed routes to 6 and 7 but disqualify those to 8 and 9.Based on the smooth formation of 8 and 9 from 2-deoxy-D-arabino-hexose (12) and ammonia, a new route to 8 and 9, through an enamine derivated from 12, is proposed.This route involves a modified Strecker degradation, which was supported by the formation of 2,3-dideoxy-D-erythro-hexose from 3-deoxy-D-ribo-hexose and glycine.
- Nyhammar, Tomas,Olsson, Kjell,Pernemalm, Per-Ake
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p. 879 - 890
(2007/10/02)
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- Synthesis of the N-Terminal Amino Acid of the Nikkomycins I, J, X, and Z
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A mixture of four stereoisomers of 2-amino-4-hydroxy-4-(5-hydroxy-2-pyridyl)-3-methylbutanoic acid (14), the N-terminal amino acid of the nikkomycin antibiotics could be synthesized in a twelve-step procedure.By comparison of 1H NMR spectra, mass spectra and of the gas chromatographic behaviour of various derivatives the constitution and relative configuration of the natural compound has been confirmed.
- Hass, Werner,Koenig, Wilfried A.
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p. 1615 - 1622
(2007/10/02)
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