114531-20-3

Upstream product

• 541-59-3 maleiimide 
• 98-80-6 phenylboronic acid 
• 34900-45-3 o-phenylenedimaleimide 

Relevant academic research and scientific papers

Low-temperature Rh-catalyzed asymmetric 1,4-addition of arylboronic acids to α,β-unsaturated carbonyl compounds

Rhodium-catalyzed asymmetric 1,4-addition of arylboronic acids to α,β-unsaturated carbonyl compounds was achieved at temperatures below 0 C using a Rh/MeO-F12-BIPHEP catalyst. The reaction of cyclohexenone or N-R-maleimide with arylboronic acids proceeded even at -80 C in the presence of the Rh catalyst. In the latter case, high enantioselectivity was observed because a low-temperature method was used, regardless of the type of substituent on maleimide.

Highly Enantioselective Synthesis of Chiral Succinimides via Rh/Bisphosphine-Thiourea-Catalyzed Asymmetric Hydrogenation

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

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).