General and highly efficient fluorinated-N-heterocyclic carbene–based catalysts for the palladium-catalyzed Suzuki–Miyaura reaction
作者:Taoping Liu、Xiaoming Zhao、Qilong Shen、Long Lu
DOI:10.1016/j.tet.2012.05.068
日期:2012.8
acid with aryl halides and heteroarylhalides, but also efficient for coupling of other heteroarylhalides and heteroaryl boronic acids. Finally, the catalyst is highly effective for Suzuki–Miyaura reaction of aryl bromides and chlorides with 0.01–0.1 mol % loading if the temperature was raised at refluxed THF/H2O.
据报道,一种通用且高效的三氟甲基化-N-杂环卡宾(NHC)基催化剂可用于钯催化的Suzuki-Miyaura反应。在催化剂的存在下,未活化的芳基氯和三氟甲磺酸与芳基硼酸的反应在室温下发生,收率好至极好(63-98%)。此外,由Pd(OAc)2 /咪唑鎓盐6a的组合产生的催化剂不仅对于杂芳基硼酸与芳基卤化物和杂芳基卤化物的偶联有效,而且对其他杂芳基卤化物和杂芳基硼酸的偶联有效。最后,如果温度在回流的THF / H 2 O上升高,则该催化剂对于0.01-0.1 mol%负载量的芳基溴化物和氯化物的Suzuki-Miyaura反应非常有效。
Rapid threefold cross-couplings with sterically bulky triarylbismuths under Pd–Cu dual catalysis
作者:Maddali L. N. Rao、Ritesh J. Dhanorkar
DOI:10.1039/c5ra23311a
日期:——
The threefold cross-coupling reactivity of sterically highly demanding bulky triarylbismuths was addressed with task specific Pd–Cu dual catalytic conditions. In this study, an unprecedented hitherto unknown cross-coupling reactivity of sterically bulky triarylbismuths was demonstrated with a diverse range of aryl iodides and bromides. The intermediacy and in situ formation of arylcopper was probed
A method for producing an unsaturated organic compound represented by the formula (3):
(Y
1
)
m-1
—R
1
—R
2
—(Y
2
)
n-1
(3)
wherein Y
1
represents R
2
or X
1
, and Y
2
represents R
1
or B(X
2
)
2
, which comprises reacting a compound represented by the formula (1):
R
1
(X
1
)
m
(1)
wherein R
1
represents an aromatic group or the like, X
1
represents a leaving group and m represents 1 or 2, with a compound represented by the formula (2):
R
2
B(X
2
)
2
}
n
(2)
wherein R
2
represents an aromatic group or the like, X
2
represents a hydroxyl group or the like, and n represents 1 or 2,
in the presence of
(a) a nickel compound selected from a nickel carboxylate, nickel nitrate and a nickel halide,
(b) a phosphine compound such as 1,4-bis(dicyclohexylphosphino) butane,
(c) an amine selected from a primary amine and a diamine such as N,N,N′,N′-tetramethyl-1,2-ethanediamine, and
(d) an inorganic base.
Nickel-Catalyzed Suzuki–Miyaura Cross-Coupling Facilitated by a Weak Amine Base with Water as a Cosolvent
作者:Xuelei Guo、Hester Dang、Steven R. Wisniewski、Eric M. Simmons
DOI:10.1021/acs.organomet.2c00197
日期:2022.6.13
development of a Ni-catalyzed Suzuki–Miyaura cross-coupling that utilizes a weak amine base and performs optimally with water as a cosolvent is reported. The aqueous amine base facilitates an equilibrium between the Ni oxidative addition complex and Ni μ-hydroxo dimers, enabling productive catalysis at low metal loadings (typically 1 mol %). A practical catalytic system is enabled by use of a commercially
据报道,开发了一种镍催化的 Suzuki-Miyaura 交叉偶联剂,该偶联剂利用弱胺碱并以水作为助溶剂实现最佳性能。含水胺碱促进 Ni 氧化加成络合物和 Ni μ-羟基二聚体之间的平衡,从而在低金属负载量(通常为 1 mol%)下实现高效催化。通过使用市售的 Ni 氧化加成络合物作为预催化剂,可以实现实用的催化体系。温和的条件允许高官能团耐受性和对复杂药物底物的应用,其中一种在 50 g 规模上以 0.5 mol% 的催化剂负载量进行了证明。
2,3-Dihydro-6-Nitroimidazo (2,1-b) Oxazole Compounds for the Treatment of Tuberculosis
申请人:Tsubouchi Hidetsugu
公开号:US20080119478A1
公开(公告)日:2008-05-22
The present invention provides a 2,3-dihydro-6-nitroimidazo[2,1-b]oxazole compound represented by the following general formula: (1) in the above formula (1), R1 represents a hydrogen atom or C1-C6 alkyl group, n represents an integer of 0 to 6, R1 and —(CH2)
n
R2 may form a spiro ring represented by the formula (30) below, together with the adjacent carbon atom (in the formula below, RRR represents a piperidyl group which may have substituents on the piperidine ring), (30) and R2 represents a benzothiazolyloxy group, quinolyloxy group, pyridyloxy group or the like. The present compound has an excellent bactericidal action against
Mycobacterium tuberculosis
, multi-drug-resistant
Mycobacterium tuberculosis
, and atypical acid-fast bacteria.