1311291-94-7Relevant academic research and scientific papers
Remarkable Ligand Effect on Rh-Catalyzed C-H-Active [3 + 2] Annulation of Ketimines and Alkynes
Fang, Yong,Luo, Yunfei,Shi, Yan,Wu, Xiang,Yang, Xiaoming,Zhao, Xu,Zhu, Chengfeng
, (2020)
Externally added ligands were first found to have a significant impact on the Rh-catalyzed C-H-active [3 + 2] annulation of ketimines and alkynes. Olefin ligands have shown remarkable promotion effect for this reaction. The olefin promoted the reaction by
A metal-free hydrogenation of 3-substituted 2H-1,4-benzoxazines
Wei, Simin,Feng, Xiangqing,Du, Haifeng
, p. 8026 - 8029 (2016/09/09)
A metal-free hydrogenation of 3-substituted 2H-1,4-benzoxazines has been successfully realized with 2.5 mol% of B(C6F5)3 as a catalyst to furnish a variety of 3,4-dihydro-2H-1,4-benzoxazines in 93-99% yields. Up to 42% ee was also achieved for the asymmetric hydrogenation with the use of a chiral diene and HB(C6F5)2.
Method for preparing 3,4-dihydrobenzo[b][1,4]oxazine derivatives
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, (2016/10/10)
The invention provides a method for preparing 3,4-dihydrobenzo[b][1,4]oxazine derivatives. The method comprises the following step: carrying out reduction reaction on [b][1,4]oxazines in the presence of hydrogen gas by using B(C6F5)3 as a catalyst to obtain the mixture containing the 3,4-dihydrobenzo[b][1,4]oxazines disclosed as Formula I. Benzo[b][1,4]oxazines in different structures are used as a substrate to synthesize the benzo[b][1,4]oxazines at high yield by using the B(C6F5)3 as the catalyst. The method has the advantages of cheap and accessible raw materials, high reaction activity, no participation of transition metals and wide substrate application range, and has huge industrialization potential.
Highly enantioselective spinol-derived phosphoric acid catalyzed transfer hydrogenation of diverse C=N-containing heterocycles
Zhang, Yiliang,Zhao, Rong,Bao, Robert Li-Yuan,Shi, Lei
supporting information, p. 3344 - 3351 (2015/05/20)
A highly efficient and enantioselective hydrogenation of diversely substituted C=N-containing heterocyclic compounds such as 3-aryl-1,4-benzoxazines and 2-arylquinolines was experimentally explored by using 1,1′-spirobiindane-7,7′-diol-derived chiral phosphoric acids as the catalyst. This method provides straightforward access to the corresponding tetrahydroquinolines and dihydro-2H-1,4-benzothiazines in high yields (85-99%) with excellent enantioselectivities (91-99%). The attractive features of this procedure, which include mild reaction conditions, operational simplicity, relatively low catalyst loading (1 mol-%), and high levels of enantioselectivities, make it a useful approach for the practical synthesis of optically active nitrogen-containing aromatic heterocycles.
Iridium-catalyzed asymmetric hydrogenation of 3-substituted 2H-1,4-benzoxazines
Gao, Kai,Yu, Chang-Bin,Wang, Duo-Sheng,Zhou, Yong-Gui
experimental part, p. 483 - 488 (2012/05/04)
The highly enantioselective hydrogenation of 3-aryl-2H-1,4-benzoxazines was achieved using the (cyclooctadiene)iridium chloride dimer/(S)-SegPhos/iodine {[Ir(COD)Cl]2/(S)-SegPhos/I2} system as catalyst with up to 92% ee. The 3-styryl
