已经建立了一系列含有咪唑基手性PNN三齿配体和可控“侧臂”基团的Mn(I)催化剂,能够使不对称二苯甲酮进行不对称氢化,具有出色的活性(高达13000吨)和出色的对映选择性(高达> 99%ee)。该协议使用K 2 CO 3作为工业上可取的碱,并且具有广泛的底物范围和官能团耐受性。此外,催化剂中的亚胺基对于获得高活性和良好的对映选择性至关重要。
accessible tridentate ferrocene-based diamine-phosphine sulfonamide (f-diaphos) ligands were successfully developed for iridium-catalyzedasymmetrichydrogenation of ketones. The f-diaphos ligands exhibited excellent enantioselectivity and superb reactivity in Ir-catalyzed asymmetrichydrogenation of ketones (for arylalkyl ketones, (S)-selectivity, up to 99.4% ee, and 100 000 TON; for diaryl ketones, (R)-selectivity
[reaction: see text] Highly efficient rhodium-catalyzed asymmetric addition of arylboronicacids to aldehydes has been realized by using chiral spiro monophosphite ligands, affording diarylmethanols in excellent yields and good enantiomeric excesses.
Cu
<sup>II</sup>
‐Catalyzed Asymmetric Hydrosilylation of Diaryl‐ and Aryl Heteroaryl Ketones: Application in the Enantioselective Synthesis of Orphenadrine and Neobenodine
作者:Yao‐Zong Sui、Xi‐Chang Zhang、Jun‐Wen Wu、Shijun Li、Ji‐Ning Zhou、Min Li、Wenjun Fang、Albert S. C. Chan、Jing Wu
DOI:10.1002/chem.201200379
日期:2012.6.11
With certain amounts of sodium tert‐butoxide and tert‐butanol as additives, catalytic amounts of an inexpensive and easy‐to‐handle copper source Cu(OAc)2⋅H2O, a commercially available and air‐stable non‐racemic dipyridylphosphine ligand, as well as the stoichiometric desirable hydride donor polymethylhydrosiloxane (PMHS), formed a versatile in situ catalyst system for the enantioselective reduction
Highly Enantioselective Synthesis of Chiral Benzhydrols via Manganese Catalyzed Asymmetric Hydrogenation of Unsymmetrical Benzophenones Using an Imidazole-Based Chiral PNN Tridentate Ligand
A series of Mn(I) catalysts containing imidazole-based chiral PNN tridentate ligands with controllable “side arm” groups have been established, enabling the asymmetricalhydrogenation of unsymmetrical benzophenones with outstanding activity (up to 13 000 TON) and excellent enantioselectivity (up to >99% ee). This protocol uses K2CO3 as an industrially desirable base and features a wide substrate scope
已经建立了一系列含有咪唑基手性PNN三齿配体和可控“侧臂”基团的Mn(I)催化剂,能够使不对称二苯甲酮进行不对称氢化,具有出色的活性(高达13000吨)和出色的对映选择性(高达> 99%ee)。该协议使用K 2 CO 3作为工业上可取的碱,并且具有广泛的底物范围和官能团耐受性。此外,催化剂中的亚胺基对于获得高活性和良好的对映选择性至关重要。
Synthesis of Ar-BINMOL Ligands by [1,2]-Wittig Rearrangement to Probe Their Catalytic Activity in 1,2-Addition Reactions of Aldehydes with Grignard Reagents
demonstrates a unique cascade chirality transfer in a [1,2]-Wittig rearrangement that leads to chiral diols with three stereogenic centers, which include a chiral sp 3 center at the alcohol and C 2 -axial chirality. Screening these ligands in the arylation of aromaticaldehydes with Grignard reagents shows that the naphthyl-substituted BINMOL promotes the aryltransferreaction in good yields (70-92%) and moderate-to-good