Allenes for Versatile Iron-Catalyzed C–H Activation by Weak O-Coordination: Mechanistic Insights by Kinetics, Intermediate Isolation, and Computation
作者:Antonis M. Messinis、Lars H. Finger、Lianrui Hu、Lutz Ackermann
DOI:10.1021/jacs.0c04837
日期:2020.7.29
ortho-regioselectivity in proximity to the weakly-coordinating carbonyl group for a range of substituted phenones and allenes. Detailed mechanistic studies, including the isolation of key intermediates, the structural characterization of an iron-metallacycle and kinetic analysis, allowed the sound elucidation of a plausible catalytic working mode. This mechanistic rationale is supported by detailed computational
γ-Trimethylsilyl-substituted allylzirconcenes in organic synthesis. Stereoselective synthesis of terminal 1,3-butadienes and functionalized vinylsilanes
作者:Jin-Hong Pi、Xian Huang
DOI:10.1016/j.tetlet.2004.01.053
日期:2004.3
hydrozirconation of trimethylsilyl-substituted terminal allenes, react with aldehydes at the γ-position to give 1,3-butadienes in one step with good stereoselectivity and undergo conjugate addition to α,β-unsaturatedaromaticketones at the α-position to selectively afford functionalized vinylsilanes in the presence of catalytic CuBr·SMe2.
A highly regio‐ and stereoselective copper‐catalyzed borylcupration of 1,2‐allenylsilanes affords an unexpected regioreversed allylic boronate bearing an extra C−Si bond at the 3‐position, with a thermodynamically disfavored Z geometry. Such stereodefined allylic boronates containing an extra alkenyl silane moiety are very useful organodimetallic reagents for organic synthesis.
Ruthenium(II)‐Catalyzed CH Functionalizations with Allenes: Versatile Allenylations and Allylations
作者:Sachiyo Nakanowatari、Lutz Ackermann
DOI:10.1002/chem.201502785
日期:2015.11.2
Ruthenium(II)‐catalyzed direct CHfunctionalization of aromatic compounds with allenes was achieved under exceedingly mild reaction conditions to yield trisubstituted allenes. The reactions of N‐methoxybenzamides proceeded smoothly in an isohypsic fashion at ambient temperature with high chemo‐ and regioselectivity, thereby providing a versatile means of accessing trisubstituted allenes. Detailed
Room-Temperature Synthesis of Trisubstituted Allenylsilanes via Regioselective C–H Functionalization
作者:Rong Zeng、Shangze Wu、Chunling Fu、Shengming Ma
DOI:10.1021/ja409861s
日期:2013.12.11
A Rh(III)-catalyzed o-C-H bond functionalization-based allenylation reaction of allenylsilanes 2 with N-methoxybenzamides 1 affords poly-substituted allenylsilanes with a wide range of attractive functional groups in moderate to excellent yields under very mild conditions (20 degrees C, compatible with ambient air and moisture). Those products may be transformed to different products with attractive structural features. Careful mechanistic studies suggest the reaction proceeds via o-rhodation, regioselective insertion, and beta-H elimination.