Vitamin D derivatives with carbo- or heterocyclic substituents at C-25, a process for their production, intermediate products and their use for producing medicaments
Visible-Light-Promoted Redox-Neutral Cyclopropanation Reactions of α-Substituted Vinylphosphonates and Other Michael Acceptors with Chloromethyl Silicate as Methylene Transfer Reagent
with chloromethyl silicate as a methylene transfer reagent has been accomplished via visible‐light‐mediated redox‐neutral catalysis. This method features broad functional group tolerance and mild conditions. In addition to α‐substituted vinylphosphonates, a range of Michael acceptors including α,β‐unsaturated acrylate, ketone, amide and sulfone are suitable substrates for this photocatalytic cyclopropanation
Amidation Reaction of Carboxylic Acid with Formamide Derivative Using SO<sub>3</sub>·pyridine
作者:Shota Kawano、Kodai Saito、Tohru Yamada
DOI:10.1246/cl.171216
日期:2018.4.5
The amidation reaction of carboxylicacid derivatives was developed using sulfur trioxide pyridinecomplex (SO3·py) as a commercially available and easily handled oxidant. This method could be applied to the reaction of various aromatic and aliphatic carboxylicacids, including optically active ones, with formamide derivatives to afford the corresponding amides in good to high yields.
We herein report an Ir-catalyzed enantioselective C(sp3)-H borylation of cyclopropanecarboxamides using a chiral bidentate boryl ligand for the first time. A variety of substrates with α-quaternary carbon centers could be compatible in this reaction to provide β-borylated products with good to excellent enantioselectivities. We have also demonstrated that the borylated products can be used as versatile
我们在此报告了首次使用手性双齿硼酸配体对环丙烷甲酰胺进行 Ir 催化的对映选择性 C(sp3)-H 硼酸化。具有 α-季碳中心的多种底物可以在该反应中相容,以提供具有良好至优异对映选择性的 β-硼酸化产物。我们还证明,硼酸化产物可用作多功能前体,参与 CB 键的立体有择转化,包括合成生物活性化合物 Levomilnacipran。
Bromomethyl Silicate: A Robust Methylene Transfer Reagent for Radical-Polar Crossover Cyclopropanation of Alkenes
new bifunctional C1 synthon: With bromomethyl silicate as a CH2 source, visible‐light‐induced cyclopropanation has been demonstrated to be amenable to the alkenes including Michael acceptors, styrene derivatives, and unactivated 1,1‐dialkyl ethylenes. In addition to the broad substrate scope, this radical‐polar crossover process is also characterized by its redox‐neutral process, mild conditions, and
NEW VITAMIN D DERIVATIVES WITH CARBO-OR HETEROCYCLIC SUBSTITUENTS AT C-25, A PROCESS FOR THEIR PRODUCTION, INTERMEDIATE PRODUCTS AND THEIR USE FOR PRODUCING MEDICAMENTS
申请人:——
公开号:US20020049344A1
公开(公告)日:2002-04-25
The invention concerns new vitamin D derivatives of general formula (I) a process for their production, their use for production of medicaments, and intermediate products used in the process.
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