Uncatalyzed conjugate addition of organozinc halides to enones in DME: a combined experimental/computational study on the role of the solvent and the reaction mechanism
calculations, prompted by the experimental aggregation study, revealed an unexpected reactionmechanism, where the coordinating capabilities of DME stabilize a transition state involving two organozinc moieties, lowering the activation energy of the reaction with respect to that seen for THF, enough to explain the fast and quantitative reactions observed experimentally and the different behaviors of
Catalytic decarboxylative alkylation of β-keto acids with sulfonamides via the cleavage of carbon–nitrogen and carbon–carbon bonds
作者:Cui-Feng Yang、Jian-Yong Wang、Shi-Kai Tian
DOI:10.1039/c1cc12790j
日期:——
An efficient decarboxylative alkylation reaction of β-keto acids with N-benzylic or N-allylic sulfonamides has been developed, for the first time, through sequential cleavage of carbonânitrogen and carbonâcarbon bonds in the presence of 10 mol% of FeCl3.
Conjugateaddition of α,β-unsaturated ketones with arylzinc species that form in situ from diethylzinc and a series of arylboronic acids by boron-zinc exchange reactions were investigated. 1,4-Addition products were formed in yields of 34-93%.
Ligand-Free Nickel-Catalysed 1,4-Addition of Arylboronic Acids to α,β-Unsaturated Carbonyl Compounds
作者:Wen Chen、Lu Sun、Xi Huang、Jiayi Wang、Yanqing Peng、Gonghua Song
DOI:10.1002/adsc.201400761
日期:2015.5.4
catalytic system has been developed for the 1,4‐addition of arylboronic acids to α,β‐unsaturatedcarbonylcompounds. With catalyst loadings of 1–2 mol%, a series of 1,4‐adducts from chalcones and cinnamates was obtained in moderate to excellent yields within 5–30 min under a nitrogen atmosphere and microwave irradiation. The 1,4‐addition of arylboronic acids to acrylates is less efficient.