1429299-19-3Relevant academic research and scientific papers
Efficient Access to Chiral β-Borylated Carboxylic Esters via Rh-Catalyzed Hydrogenation
Liu, Gang,Li, Anqi,Qin, Xueyuan,Han, Zhengyu,Dong, Xiu-Qin,Zhang, Xumu
, p. 2844 - 2848 (2019/04/26)
Rh/bisphosphine?thiourea ligand (ZhaoPhos)-catalyzed asymmetric hydrogenation of (Z)-β-substituted-β-boryl-α,β-unsaturated esters was successfully developed, furnishing a variety of chiral β-borylated carboxylic esters with high yields and excellent enantioselectivities (up to 99% yield and >99% ee). The gram-scale asymmetric hydrogenation was performed efficiently in the presence of only 0.05 mol% (S/C=2 000) catalyst loading with full conversion, 99% yield and 99% ee. Moreover, the hydrogenation product was easily converted to other versatile synthetic intermediates, such as methyl (S)-3-hydroxy-3-phenylpropanoate and methyl (S)-3-(furan-2-yl)-3-phenylpropanoate. (Figure presented.).
Application of bidentate oxazoline-carbene ligands with planar and central chirality in asymmetric β-Boration of α,β-unsaturated esters
Niu, Zonghong,Chen, Jianqiang,Chen, Zhen,Ma, Manyuan,Song, Chun,Ma, Yudao
, p. 602 - 608 (2016/09/09)
A series of new oxazoline-substituted imidazolium salts based on [2.2]paracyclophane were synthesized and characterized. The new bidentate oxazoline-carbene precursor with planar and central chirality had significant advantage than the bicyclic 1,2,4-triazolium salt derived from [2.2]paracyclophane as a monodentate carbene ligand in Cu(I)-catalyzed asymmetric β-boration of α,β-unsaturated esters, giving the desired products in high enantioselectivities and yields.
Asymmetric β-boration of α,β-unsaturated carbonyl compounds with chiral Rh[bis(oxazolinyl)phenyl] catalysts
Toribatake, Kenji,Zhou, Li,Tsuruta, Ayae,Nishiyama, Hisao
supporting information, p. 3551 - 3560 (2013/05/08)
Chiral rhodium[bis(oxazolinyl)phenyl] complexes exhibited high catalytic activity for the β-boration of α,β-unsaturated esters, ketones, and amides with bis(pinacolato)diboron in the presence of sodium tert-butoxide to attain high enantioselectivity of up to 97%. The substrate scope and catalytic mechanism were discussed.
