Amide-Directed Catalytic Asymmetric Hydroboration of Trisubstituted Alkenes
作者:Sean M. Smith、James M. Takacs
DOI:10.1021/ja908257x
日期:2010.2.17
rhodium-catalyzed reaction is stereospecific. In addition, simple TADDOL-derived phenyl monophosphite ligands in combination with Rh(nbd)(2)BF(4) afford highly enantioselective catalysts (seven examples, 91-98% ee). These catalysts provide an alternative methodology to prepare Felkin or anti-Felkin acetate-aldol products and related derivatives that are obtainable from the intermediate chiral organoboranes
Design and Evaluation of Inclusion Resolutions, Based on Readily Available Host Compounds
作者:Simona Müller、Marcel Cyrus Afraz、René de Gelder、Gerry J. A. Ariaans、Bernard Kaptein、Quirinus B. Broxterman、Alle Bruggink
DOI:10.1002/ejoc.200400613
日期:2005.3
of enantiomers through selective crystallisation of diastereomeric inclusioncompounds can extend the scope of traditional racemate resolution beyond salt forming compounds. To assess the practical value of this approach the literature was carefully screened and promising results were checked. Also an extensive range of new inclusion hosts suitable for resolution processes, derived from simple hydroxyand
Synthesis of β-Lactams by Palladium(0)-Catalyzed C(sp<sup>3</sup>)−H Carbamoylation
作者:David Dailler、Ronan Rocaboy、Olivier Baudoin
DOI:10.1002/anie.201703109
日期:2017.6.12
A general and user‐friendly synthesis of β‐lactams is reported that makes use of Pd0‐catalyzed carbamoylation of C(sp3)−H bonds, and operates under stoichiometric carbon monoxide in a two‐chamber reactor. This reaction is compatible with a range of primary, secondary and activated tertiary C−H bonds, in contrast to previous methods based on C(sp3)−H activation. In addition, the feasibility of an enantioselective
Nickel-Catalyzed Asymmetric Addition of Alkyne CH Bonds across 1,3-Dienes Using Taddol-Based Chiral Phosphoramidite Ligands
作者:Masamichi Shirakura、Michinori Suginome
DOI:10.1002/anie.201001188
日期:——
Enantioenriched 3‐methyl‐1,4‐enynes are the products of the title reaction. The terminal α‐siloxy‐sec‐alkyl groups were then converted into γ‐oxoalkyl groups by rhodium‐catalyzed conjugate alkynyl addition to α,β‐unsaturated ketones through cleavage of the alkynyl CC bond.
Enantioselective Rhodium-Catalyzed [2 + 2 + 2] Cycloadditions of Terminal Alkynes and Alkenyl Isocyanates: Mechanistic Insights Lead to a Unified Model that Rationalizes Product Selectivity
作者:Derek M. Dalton、Kevin M. Oberg、Robert T. Yu、Ernest E. Lee、Stéphane Perreault、Mark Emil Oinen、Melissa L. Pease、Guillaume Malik、Tomislav Rovis
DOI:10.1021/ja905065j
日期:2009.11.4
describes the development and scope of the asymmetric rhodium-catalyzed [2 + 2 + 2] cycloaddition of terminal alkynes and alkenyl isocyanates leading to the formation of indolizidine and quinolizidine scaffolds. The use of phosphoramidite ligands proved crucial for avoiding competitive terminal alkyne dimerization. Both aliphatic and aromatic terminal alkynes participate well, with product selectivity a function