From Alkenes to Isoxazolines via Copper-Mediated Alkene Cleavage and Dipolar Cycloaddition
作者:Mingchun Gao、Yuansheng Gan、Bin Xu
DOI:10.1021/acs.orglett.9b02748
日期:2019.9.20
transformation is reported, along with selective C═C double bond cleavage and dipolar cycloaddition reaction from simple alkenes and inexpensive copper nitrate. Various transformations demonstrate the generality of this method. Further mechanistic investigation indicates a novel ionic pathway for alkene cleavage and highlights the coeffect of iodide and boric acid as additives on the inhibition of well-documented
Preparation of indium nitronates and their Henry reactions
作者:Raquel G. Soengas、Rita Acúrcio、Artur M. S. Silva
DOI:10.1039/c4ob01468e
日期:——
Indium nitronates were readily prepared from commercially available nitroalkanes by transmetallation of the corresponding lithium nitronates with indium salts. The Henryreaction of this indium organometallics with aldehydes afforded β-nitroalkanols in moderate to high yields. The use of chiral sugar aldehydes furnished the corresponding carbohydrate-derived β-nitroalkanols with excellent stereoselectivity
New phosphino‐oxazoline ligands have been developed, and the ligands have been used for Cu‐catalysed enantioselective conjugate additions to (E)‐nitroalkenes.
已开发出新的膦基-恶唑啉配体,该配体已被用于铜催化的(E)-硝基烯烃的铜对映体选择性共轭加成反应。
Enantioselective synthesis of gabapentin analogues via organocatalytic asymmetric Michael addition of α-branched aldehydes to β-nitroacrylates
Michaeladdition reaction of α-branched aldehydes to β-nitroacrylates was successfully carried out by using a mixed catalyst consisting of a primary amino acid, L-phenylalanine, and its lithium salt to give β-formyl-β′-nitroesters having a quaternary carbon centre in good yields (up to 85%) with high enantioselectivity (up to 98% ee). By using benzyl β-nitroacrylates as Michael acceptors, the obtained
An efficient method for the synthesis of β-nitro alcohols from nitro alkanes and aldehydes in aqueous phosphate buffer under neutral pH conditions at room temperature is reported. In the case of higher nitro alkanes, the reaction showed very good diastereoselectivity to give syn β-nitro alcohols in preference to their anti products.