A highly diastereoselective cross-coupling reaction of an α-bromo-α-fluoro-β-lactam with a wide range of aryl Grignard reagents was catalyzed by Ni/bis(oxazoline) in yields of up to 98%. The product was obtained diastereoselectively as an anti-isomer. This is the first successful α-arylation of an α-fluoro-β-lactam to produce diverse α-aryl-α-fluoro-β-lactams.
Ni /双(恶唑啉)催化α-溴-α-氟-β-内酰胺与多种芳基格氏试剂的高度非对映选择性交叉偶联反应,收率高达98%。非对映选择性地获得该产物作为反异构体。这是α-氟-β-内酰胺成功生产出多种α-芳基-α-氟-β-内酰胺的第一个成功的α-芳基化反应。
Silver-Catalyzed Enantioselective Propargylic C–H Bond Amination through Rational Ligand Design
作者:Minsoo Ju、Emily E. Zerull、Jessica M. Roberts、Minxue Huang、Ilia A. Guzei、Jennifer M. Schomaker
DOI:10.1021/jacs.0c05726
日期:2020.7.29
precursors from abundant C-H bonds. Herein, we report a regio- and enantioselectivesynthesis of -alkynyl -aminoalcohols via a silver-catalyzed propargylic C-H amination. The protocol was enabled by a new bis(oxazoline) (BOX) ligand designed via a rapid structure-activity relationship (SAR) analysis. The method utilizes accessible carbamateesters bearing -propargylic C-H bonds and furnishes versatile products
Stereoselective Copper-Catalyzed Intramolecular Alkene Aminooxygenation: Effects of Substrate and Ligand Structure on Selectivity
作者:Monissa C. Paderes、Sherry R. Chemler
DOI:10.1002/ejoc.201100444
日期:2011.7
A new protocol for diastereoselective copper-catalyzed intra-molecular alkene aminooxygenation, which provides methyleneoxy-functionalized disubstituted pyrrolidines and five-membered cyclic ureas from the corresponding γ-alkenyl sulfonamides and N-allylureas, is reported. In addition, some success was achieved in enantioselective desymmetrizations reactions. We discovered that the level of enantioselectivity
报道了一种非对映选择性铜催化分子内烯烃氨基氧化的新方案,该方案从相应的 γ-烯基磺酰胺和 N-烯丙基脲中提供亚甲氧基官能化的二取代吡咯烷和五元环脲。此外,对映选择性去对称化反应也取得了一些成功。我们发现对映选择性和非对映选择性的水平可以通过选择铜 (II) 配体和底物 N 取代基来调节。
(4+3) Annulation of Donor‐Acceptor Cyclopropanes and Azadienes: Highly Stereoselective Synthesis of Azepanones
作者:Stefano Nicolai、Jérôme Waser
DOI:10.1002/anie.202209006
日期:2022.9.5
Azepanones are important and widespread seven-membered heterocycles, but their synthesis is challenging. A convergent method to access these scaffolds was developed relying on a (4+3) annulation reaction of azadienes and donor-acceptor cyclopropanes. Good to excellent yields and high diastereoselectivity were achieved using Yb(OTf)3 as the catalyst. Asymmetric induction was possible with Cu(OTf)2 in
Flame-retardant resin composition and electric wire
申请人:POLYPLASTICS CO. LTD.
公开号:EP0320159A1
公开(公告)日:1989-06-14
The invention provides a flame-retardant resin composition characterised in that it comprises (A) an aromatic polyester prepared by condensation polymerization between (a) a component substantially comprising an aromatic dicarboxylic acid or an ester-forming derivative thereof and (b) a component substantially comprising an aliphatic diol or an ester-forming derivative thereof,
(B) 0.1 to 30% by weight based on the total amount of the composition of a compound represented by the general formula (1) or (2)
wherein X represents a halogen atom; Y₁ and Y₂ each represent a group selected from hydroxyl, carboxyl, glycidyl ester and glycidyl ether groups; Z is a monovalent or divalent organic group and n is an integer of 1 or more and
(C) 0.1 to 30% by weight based on the total amount of the composition of a compound represented by the general formula (3):
L₁-M-L₂ (3)
wherein M is a divalent organic group L₁ and L₂ may be the same or different from each other and each represent a 3- to 8-membered cyclic reactive group selected from those having the general formulae (4) to (7):
in which each of R₁, R₂ and R₃ represent a divalent organic group wherein a hydrogen atom directly bonded to the ring may be substituted with an alkyl and/or aryl group.
The invention also includes electric wires coated therewith.