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
Palladium‐ and Rhodium‐Catalyzed Dynamic Kinetic Resolution of Racemic Internal Allenes Towards Chiral Pyrazoles
作者:Lukas J. Hilpert、Simon V. Sieger、Alexander M. Haydl、Bernhard Breit
DOI:10.1002/anie.201812984
日期:2019.3.11
resolution (DKR) of racemic allenes leading to N‐allylated pyrazoles is described. Such compounds are of enormous interest in medicinal chemistry as certified drugs and potential drug candidates. The new methods feature high chemo‐, regio‐ and enantioselectivities aside from displaying a broad substrate scope and functional group compatibility. A mechanistic rational accounting for allene racemization and trans‐alkene
Iron-Catalyzed Contrasteric Functionalization of Allenic C(sp<sup>2</sup>)–H Bonds: Synthesis of α-Aminoalkyl 1,1-Disubstituted Allenes
作者:Yidong Wang、Sarah G. Scrivener、Xiao-Dong Zuo、Ruihan Wang、Philip N. Palermo、Ethan Murphy、Austin C. Durham、Yi-Ming Wang
DOI:10.1021/jacs.1c07512
日期:2021.9.22
An iron-catalyzed C–H functionalization of simple monosubstituted allenes is reported. An efficient protocol for this process was made possible by the use of a newly developed electron-rich and sterically hindered cationic cyclopentadienyliron dicarbonyl complex as the catalyst and N-sulfonyl hemiaminal ether reagents as precursors to iminium ion electrophiles. Under optimized conditions, the use of
作者:Ilfir R. Ramazanov、Alsu V. Yaroslavova、Usein M. Dzhemilev、Oleg M. Nefedov
DOI:10.1016/j.tetlet.2010.09.093
日期:2010.12
The reactions of aluminum carbenoids with alkyl- and phenyl-substituted allenes and cyclic allenes are studied. An efficient method for the synthesis of substituted spiropentanes was developed. 1,2-Cyclononadiene was selectively converted into bicyclo[7.1.0]dec-1-ene. An unusual transformation of α-methylphenylallene into a spiroindane derivative under the action of Et3Al–CH2I2 was found.
研究了铝类化合物与烷基和苯基取代的烯和环烯的反应。开发了一种有效的合成取代螺环戊烷的方法。将1,2-环己二烯选择性地转化为双环[7.1.0] dec-1-ene。发现在Et 3 Al–CH 2 I 2的作用下,α-甲基苯丙烯不寻常地转变为螺茚满衍生物。
Electrophilic additions to allenes—II
作者:Dennis G. Garratt、Pierre L. Beaulieu、M.Dominic Ryan
DOI:10.1016/s0040-4020(01)83115-x
日期:1980.1
Benzeneselenenyl chloride reacts with 1,3-dialkyl-substituted allenes in methylene chloride solution to give 1:1-adducts. Attack by selenium is found to occur exclusively at the central allenic carbon. In contrast to the analogous reaction of arenesulphenyl chlorides, the preferential formation of the Z-alkene is observed. A mechanism involving the preequilibrium formation of alkylideneseleniranium