Palladium(0)-Catalyzed Cross-Coupling of 1,1-Diboronates with Vinyl Bromides and 1,1-Dibromoalkenes
作者:Huan Li、Zhikun Zhang、Xianghang Shangguan、Shan Huang、Jun Chen、Yan Zhang、Jianbo Wang
DOI:10.1002/anie.201407000
日期:2014.10.27
Palladium‐catalyzed cross‐coupling reactions of 1,1‐diboronates with vinylbromides and dibromoalkenes were found to afford 1,4‐dienes and allenes, respectively. These reactions utilize the high reactivities of both 1,1‐diboronates and allylboron intermediates generated in the initial coupling.
Rhodium‐Catalyzed Parallel Kinetic Resolution of Racemic Internal Allenes Towards Enantiopure Allylic 1,3‐Diketones
作者:Lukas J. Hilpert、Bernhard Breit
DOI:10.1002/anie.201903365
日期:2019.7.15
parallel kinetic resolution of racemic 1,3‐disubstituted allenes by means of a rhodium‐catalyzed addition to 1,3‐diketones furnishing enantiopure allylic 1,3‐diketones is described. Mechanistic experiments demonstrate that the different allene enantiomers react in parallel to either the diastereomeric E‐ or Z‐allylic 1,3‐diketones with the same absoluteconfiguration of the newly formed stereogenic
Ligand-controlled regioselective palladium-catalyzed decarboxylative hydrogenolysis of propargylic formates is described. A wide range of allenes and alkynes were obtained by using either 1,2-diphenylphosphinoethane (DPPE) or 1,6-bisdiphenylphosphinohexane (DPPH) as a catalyst ligand.
Copper(I) Halide Promoted Diastereoselective Synthesis of Chiral Propargylamines and Chiral Allenes using 2-Dialkylaminomethylpyrrolidine, Aldehydes, and 1-Alkynes
作者:Ramani Gurubrahamam、Mariappan Periasamy
DOI:10.1021/jo302534f
日期:2013.2.15
Copper bromide promoted reactions of aldehydes, 1-alkynes, and chiral 2-dialkylaminomethylpyrrolidine at 25 °C give the corresponding chiralpropargylamine derivatives in up to 96% yield and 99:1 dr that are readily converted to the corresponding disubstitued chiralallenes in up to 81% yield and 99% ee upon reaction with CuI in dioxane at 100 °C.
Gold(I)-Catalysed Hydroarylation of 1,3-Disubstituted Allenes with Efficient Axial-to-Point Chirality Transfer
作者:Daniel R. Sutherland、Luke Kinsman、Stuart M. Angiolini、Georgina M. Rosair、Ai-Lan Lee
DOI:10.1002/chem.201800209
日期:2018.5.11
Hydroarylation of enantioenriched 1,3‐disubstituted allenes has the potential to proceed with axial‐to‐point chirality transfer to yield enantioenriched allylated (hetero)aryl compounds. However, the gold‐catalysed intermolecular reaction was previously reported to occur with no chirality transfer owing to competing allene racemisation. Herein, we describe the development of the first intermolecular hydroarylations