Palladium-catalyzed asymmetric alkylation in the synthesis of cyclopentanoid and cycloheptanoid core structures bearing all-carbon quaternary stereocenters
作者:Allen Y. Hong、Nathan B. Bennett、Michael R. Krout、Thomas Jensen、Andrew M. Harned、Brian M. Stoltz
DOI:10.1016/j.tet.2011.10.031
日期:2011.12
reagents enabled divergent access to γ-quaternary acylcyclopentenes through a ringcontraction pathway or γ-quaternary cycloheptenones through a carbonyl transposition pathway. Synthetic applications of these compounds were explored through the preparation of mono-, bi-, and tricyclic derivatives that can serve as valuable intermediates for the total synthesis of complex natural products. This work complements
The use of water as a nucleophile for Michaeladditions is still a challenge in organic chemistry. In this report we describe the use of aminoacids as catalysts for the Michaeladdition of water to ?,?-unsaturated ketones. All 20 proteinogenic aminoacids were screened and L-lysine was identified as the best candidate. To obtain a better insight and to determine the minimum requirements of the catalyst
作者:Bi-Shuang Chen、Verena Resch、Linda G. Otten、Ulf Hanefeld
DOI:10.1002/chem.201405579
日期:2015.2.9
enantioselective Michael addition using water as both nucleophile and solvent has to date proved beyond the ability of synthetic chemists. Herein, the direct, enantioselective Michael addition of water in water to prepare important β‐hydroxy carbonyl compounds using wholecells of Rhodococcus strains is described. Good yields and excellent enantioselectivities were achieved with this method. Deuterium
CoTPP-catalyzed reaction of saturated bicyclic endoperoxides
作者:Metin Balci、Nihat Akbulut
DOI:10.1016/s0040-4020(01)96533-0
日期:1985.1
Saturated bicyclicendoperoxides were exposed to CoTPP (Cobalt-meso-tetraphenylporphyrine) in chloroform, the peroxide bond was cleaved and a mixture of products arising from fragmentation and reduction obtained.