Iodine as an extremely powerful catalyst for the acetylation of alcohols under solvent-free conditions
作者:Prodeep Phukan
DOI:10.1016/j.tetlet.2004.04.076
日期:2004.6
Iodine was found to promote quantitative acetylation of alcohols in a very short time with an equimolar amount of acetic anhydride undersolvent-freeconditions at room temperature.
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
Stereocontrol in Palladium-Catalyzed Propargylic Substitutions: Kinetic Resolution to give Enantioenriched 1,5-Enynes and Propargyl Acetates
作者:Michael J. Ardolino、Meredith S. Eno、James P. Morken
DOI:10.1002/adsc.201300720
日期:2013.11.25
Kineticresolution during the catalytic allyl-propargyl cross-coupling with chiral starting materials can be accomplished with a chiral Palladium catalyst. These reactions offer ready access to enantiomerically enriched enyne products from simple readily available starting materials.
Enantioselective Copper-Catalysed Propargylic Substitution: Synthetic Scope Study and Application in Formal Total Syntheses of (+)-Anisomycin and (−)-Cytoxazone
作者:Remko J. Detz、Zohar Abiri、Remi le Griel、Henk Hiemstra、Jan H. van Maarseveen
DOI:10.1002/chem.201003727
日期:2011.5.16
indoles excellent ee values were obtained (up to 98 % ee). The versatility of the propargylic amines obtained was demonstrated by their further elaboration to formaltotalsyntheses of the antibiotic (+)‐anisomycin and the cytokine modulator (−)‐cytoxazone.
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