Organoselenium-Catalyzed Regioselective C−H Pyridination of 1,3-Dienes and Alkenes
作者:Lihao Liao、Ruizhi Guo、Xiaodan Zhao
DOI:10.1002/anie.201610657
日期:2017.3.13
organoselenium‐catalyzed regioselective C−H pyridination of 1,3‐dienes to form pyridinium salts has been developed. This method was also successfully applied to direct C−H pyridination of alkenes. Fluoropyridinium reagents, or initially loaded pyridine derivatives, acted as pyridine sources in the pyridination reactions. The obtained pyridinium salts could be further converted under different conditions
Rh-Catalyzed Regio- and Enantioselective Allylic Phosphinylation
作者:Bing Li、Min Liu、Sajid Ur Rehman、Changkun Li
DOI:10.1021/jacs.2c00239
日期:2022.2.23
and enantioselective synthesis of allylic phosphine oxides in the presence of a chiral bisoxazoline-phosphine ligand. The application of α-hydroxylalkylphosphine oxides to keep the low concentration of the secondary phosphine oxides is essential for the high yields. The addition of diphenyl phosphoric acid was found to not only activate allylic alcohols but also accelerate the carbon–phosphorus bond
Regio‐ and Diastereoselective Rhodium‐Catalyzed Allylic Substitution with Unstabilized Benzyl Nucleophiles
作者:Debasis Pal、Timothy B. Wright、Ryan O'Connor、P. Andrew Evans
DOI:10.1002/anie.202008071
日期:2021.2.8
rhodium‐catalyzed allylic substitution of challenging alkyl‐substituted secondary allylic carbonates with benzylzinc reagents, which are prepared from widely available benzyl halides. This process utilizes rhodium(III) chloride as a commercially available, high‐oxidation state and bench‐stable pre‐catalyst to provide a rare example of a regio‐ and diastereoselective allylic substitution in the absence of an
An iridium-catalyzedasymmetric synthesis of branched allylic phosphine compounds under mild conditions is reported. Products bearing various functional groups can be synthesized with excellent stereoselectivity (up to 99.9 % ee) and regioselectivity. The employment of phosphine sulfides with relatively low deactivation capacity against metal catalysts is crucial for the success of this reaction.