Development of a Rhodium(II)-Catalyzed Chemoselective C(sp<sup>3</sup>)H Oxygenation
作者:Yun Lin、Lei Zhu、Yu Lan、Yu Rao
DOI:10.1002/chem.201502140
日期:2015.10.12
We report the first example of RhII‐catalyzed chemoselective double C(sp3)Hoxygenation, which can directly transform various toluene derivatives into highly valuable aromatic aldehydes with great chemoselectivity and practicality. The critical combination of catalyst Rh(OAc)2, oxidant Selectfluor, and solvents of TFA/TFAA promises the successful delivery of the oxidation with satisfactory yields
Cobalt-Catalyzed Asymmetric Hydrogenation of 1,1-Diarylethenes
作者:Jianhui Chen、Chenhui Chen、Chonglei Ji、Zhan Lu
DOI:10.1021/acs.orglett.6b00453
日期:2016.4.1
Highlyenantioselective cobalt-catalyzed hydrogenation of 1,1-diarylethenes was developed by using bench-stable chiral oxazoline iminopyridine–cobalt complexes as precatalysts. A unique o-chloride effect was observed to achieve high enantioselectivity. Easy removal as well as further transformations of the chloro group make this protocol a potentially useful alternative to synthesize various chiral
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
Erbium trifluoromethanesulfonate catalyzed Friedel–Crafts acylation using aromatic carboxylic acids as acylating agents under monomode-microwave irradiation
作者:Phuong Hoang Tran、Poul Erik Hansen、Hai Truong Nguyen、Thach Ngoc Le
DOI:10.1016/j.tetlet.2014.12.038
日期:2015.1
Erbium trifluoromethanesulfonate is found to be a good catalyst for the Friedel–Craftsacylation of arenes containing electron-donating substituents using aromatic carboxylicacids as the acylating agents under microwave irradiation. An effective, rapid and waste-free method allows the preparation of a wide range of aryl ketones in good yields and in short reaction times with minimum amounts of waste
Highly Enantioselective Cobalt-Catalyzed Hydroboration of Diaryl Ketones
作者:Wenbo Liu、Jun Guo、Shipei Xing、Zhan Lu
DOI:10.1021/acs.orglett.0c00293
日期:2020.4.3
A highlyenantioselective cobalt-catalyzed hydroboration of diaryl ketones with pinacolborane was developed using chiral imidazole iminopyridine as a ligand to access chiral benzhydrols in good to excellent yields and ee. This protocol could be carried out in a gram scale under mild reaction conditions with good functional group tolerance. Chiral biologically active 3-substituted phthalide and (S)-neobenodine