42856-57-5Relevant articles and documents
Ruthenium(II)-Catalyzed Hydroarylation of Maleimides Using Carboxylic Acids as a Traceless Directing Group
Mandal, Anup,Sahoo, Harekrishna,Dana, Suman,Baidya, Mahiuddin
supporting information, p. 4138 - 4141 (2017/08/15)
An efficient Ru(II)-catalyzed hydroarylation of maleimides with ready-stock aryl carboxylic acids has been developed based on weak carboxylate-directed ortho-C-H alkylation and concomitant decarboxylation processes, fabricating 3-aryl succinimides, a recurrent scaffold in drug molecules, in high yields (up to 97%). The protocol features operational simplicity, avoids the need for precious metal additives/oxidants, and offers broad substrate scope with formal meta- and para-selectivities. It represents the first example of Ru(II)-catalyzed direct arylation of maleimides with unbiased benzoic acids.
Highly Enantioselective Synthesis of Chiral Succinimides via Rh/Bisphosphine-Thiourea-Catalyzed Asymmetric Hydrogenation
Han, Zhengyu,Li, Pan,Zhang, Zongpeng,Chen, Caiyou,Wang, Qian,Dong, Xiu-Qin,Zhang, Xumu
, p. 6214 - 6218 (2016/09/09)
We have successfully developed a highly enantioselective hydrogenation of various 3-aryl and 3-methyl maleinimides to access enantiomerically pure 3-substituted succinimides catalyzed by Rh/bisphosphine-thiourea (ZhaoPhos). This efficient catalytic system furnished the desired 3-substituted succinimide products with high yields and enantioselectivities (up to 99% yield, full conversions, almost all 3-aryl succinimide products up to 99% ee, and 3-methyl succinimide with 83% ee). Our catalytic system has a strong substrate tolerance and generality. Whether the N-substituted group of maleinimides is H or other protecting groups, the maleinimides were hydrogenated well (up to >99% ee, 99% yield). Moreover, the hydrogenation succinimide products can be readily utilized for the construction of biologically active molecules, such as chiral amides and pyrrolidines.
Direct Synthesis of Chiral 3-Arylsuccinimides by Rhodium-Catalyzed Enantioselective Conjugate Addition of Arylboronic Acids to Maleimides
Gopula, Balraj,Yang, Shu-Han,Kuo, Ting-Shen,Hsieh, Jen-Chieh,Wu, Ping-Yu,Henschke, Julian P.,Wu, Hsyueh-Liang
supporting information, p. 11050 - 11055 (2015/11/10)
Chiral rhodium catalysts comprising 2,5-diaryl- substituted bicyclo[2.2.1]diene ligands L1-L10 were utilized in the enantioselective 1,4-addition reaction of arylboronic acids to N-substituted maleimides. In the presence of 2.5mol % of RhI/L2, enantioenriched conjugate addition adducts were isolated in 72-99 % yields with 86-98 %ee. This protocol offers a convenient method to access a variety of 3-arylsuccinimides in a highly enantioselective manner. Maleimides with readily cleavable N-protecting groups were tolerated enabling the synthesis of useful synthetic intermediates. Pyrrolidine 4, a biologically active compound, and pyrrolidine 5, an ent-precursor to an HSD-1 inhibitor, were synthesized to demonstrate the utility of this method. The road to rhodium! Enantioselective conjugate addition of a range of arylboronic acids to variously N-substituted maleimides, catalyzed by RhI complexes prepared in situ using chiral bicyclo[2.2.1]diene ligands, afforded the corresponding 3-arylsuccinimides with up to 98 %ee at 50 C (see scheme).