Gold(I)-Catalyzed Highly Regio- and Stereoselective Decarboxylative Amination of Allylic <i>N</i>-Tosylcarbamates via Base-Induced Aza-Claisen Rearrangement in Water
作者:Dong Xing、Dan Yang
DOI:10.1021/ol100056f
日期:2010.3.5
A gold(I)-catalyzed decarboxylative amination of allylic N-tosylcarbamates via base-induced aza-Claisen rearrangement has been developed. A variety of substituted N-tosyl allylic amines were obtained in good yield, excellent regioselectivity, and high to excellent stereoselectivity. This transformation could be performed either in H2O or in one pot directly from allylic alcohols and therefore represents
Nucleophilic addition of dialkylzincs to aldehydes in hydrocarbon solvents is markedly accelerated by the presence of a catalytic amount of a β-dialkylamino alcohol. Use of certain sterically constrained chiral amino alcohols such as 3-exo-(dimethylamino)isoborneol or 1-t-butyl-2-piperidinoethanol effects highly enantioselective catalysis giving secondary alcohols in up to 99% ee. Dimethyl-, diethyl-
The present invention relates to the chemical synthesis of vittatalactone, the aggregation pheromone of the striped cucumber beetle,
Acalymma vittatum.
Iterative Deoxypropionate Synthesis Based on a Copper-Mediated Directed Allylic Substitution: Formal Total Synthesis of Borrelidin (C3–C11 Fragment)
作者:Christian Herber、Bernhard Breit
DOI:10.1002/chem.200600343
日期:2006.8.25
alkylation strategies such as enolate reactivity as well as costs and problems associated with the chiral auxiliary. Practicability of this new method is demonstrated through application in natural product syntheses. Thus, an efficient synthesis of the northern part of the angiogenesis inhibitor borrelidin (28), the deoxypropionate building block 27, could be devised, representing a formal total synthesis
Engineering Catalysts for Enantioselective Addition of Diethylzinc to Aldehydes with Racemic Amino Alcohols: Nonlinear Effects in Asymmetric Deactivation of Racemic Catalysts
Correct additions make a difference: Asymmetric deactivation and asymmetric amplification concepts coupled with a high-throughput screening technique provided a successful strategy for designing a highly enantioselective catalytic system by simple combination of a racemic aminoalcohol (rac-DB) and a nonracemic additive (AA). The example in the scheme shows the conversion of 1 into 2 with up to 92