28783-51-9Relevant articles and documents
Free-Radical Carbo-Alkenylation of Olefins: Scope, Limitations and Mechanistic Insights
Beniazza, Redouane,Liautard, Virginie,Poittevin, Clément,Ovadia, Benjamin,Mohammed, Shireen,Robert, Frédéric,Landais, Yannick
supporting information, p. 2439 - 2447 (2017/02/23)
The three-component free-radical carbo-alkenylation of electron-rich olefins has been studied, varying the substitution pattern in the alkene, in the radical precursor and in the final acceptor. New vinylsulfones were also prepared and their reactivity investigated. The scope and limitations of the process was established, and the reaction mechanism clarified using selected dienes as radical clocks. It was thus recognised that the reversible addition onto the olefin of the released sulfonyl group is an important event, which should not be overlooked when using such multicomponent carbo-alkenylation reactions.
Synthesis and lipase-catalyzed asymmetric acetylation of 3-hydroxyl-2-hydroxymethylpropanal acetals
Egri, Gabriella,Fogassy, Elemer,Novak, Lajos,Poppe, Laszlo
, p. 547 - 557 (2007/10/03)
Prochiral dialkylacetal derivatives of 3-hydroxy-2-hydroxymethylpropanal 6a-e were synthesized from the corresponding 2-substituted diethyl malonates 5a-e and subjected to asymmetric enzymatic acetylation. The diethyl malonates 5a-f were prepared from diethyl chloromethylenemalonate 3 by using either a one- or a two-step process. Asymmetric acetylation of 3-hydroxy-2-hydroxymethylpropanal diethyl acetal 6b with several enzymes was studied first, showing the highest enantiotopic selectivity with lipase from Pseudomonas fluorescens (PFL). Solvent effect was also investigated: the best selectivity was obtained in a mixture of hexane and diethyl ether. Furthermore, several other acetals 6a-e were also tested under the optimal acetylation conditions.