Results 101 to 110 of about 90,564 (138)

Sn(OTf)2-Catalyzed (3 + 2) Cycloaddition/Sulfur Rearrangement Reaction of Donor-Acceptor Cyclopropanes with Indoline-2-thiones.

Organic Letters
The (3 + 2) cycloaddition/sulfur rearrangement reaction of donor-acceptor cyclopropanes bearing a single keto acceptor with indoline-2-thiones has been realized.
Yan Jiang, Hao-Jie Ma, Chen-Ying Zhai, Xueling Wang   +3 more
semanticscholar   +1 more source

Hexafluoroisopropanol Catalyzed Ring‐Opening‐Cyclization of Donor−Acceptor Cyclopropanes with Primary Amines

Annalen der Pharmacie
We reveal here a metal‐free, ring‐opening‐cyclization of donor‐acceptor cyclopropanes with primary amines to synthesize functionalized dihydropyrroles. This protocol avoids inert conditions and solvents promoted by hexafluoroisopropanol (HFIP).
Srinivasarao Yaragorla, Rajeshwari Tangellapally, Doma Arun   +2 more
semanticscholar   +1 more source

Strain-Releasing Hydrogenation of Donor-Acceptor Cyclopropanes and Cyclobutanes via Electrochemical Site Selective Carbonyl Reduction.

Journal of Organic Chemistry
An acid or hydrogen gas-free electrochemical protocol is established for the hydrogenation of strained rings (cyclopropane and cyclobutane) at room temperature and atmospheric pressure.
Nakshatra Banerjee, Rakesh Kumar, Biswadeep Manna, Prabal Banerjee   +3 more
semanticscholar   +1 more source

Sc(OTf)3‐Catalyzed Ring‐Opening Reactions of Donor‐Acceptor Cyclopropanes/Bicyclo[1.1.0]butanes: Access to 3‐Substituted Chromenones, Cyclopenta[b]chromenones and 2‐Aminobicyclo[2.1.1]hexanes

Advanced Synthesis & Catalysis
A robust Sc(OTf)3‐catalyzed and DBN‐assisted strain‐release‐driven ring‐opening‐annulation reaction of ortho‐hydroxyarylenaminones with an array of 2‐aryl‐substituted cyclopropane 1,1‐diesters as perfect 3C atoms reactive synthons to create three new C‐C,
S. Samanta, P. Rani
semanticscholar   +1 more source

Converting Strain Release into Aromaticity Loss for Activation of Donor-Acceptor Cyclopropanes: Generation of Quinone Methide Traps for C-Nucleophiles.

Organic Letters
Here, we present a new approach for the activation of donor-acceptor cyclopropanes in ring-opening reactions, which does not require the use of a Lewis or Brønsted acid as a catalyst.
V. Shorokhov, Beauty K. Chabuka, T. P. Tikhonov, Anastasia V. Filippova, S. S. Zhokhov, V. Tafeenko, I. Andreev, N. Ratmanova, M. Uchuskin, I. Trushkov, Igor V. Alabugin, O. Ivanova   +11 more
semanticscholar   +1 more source

1,3-Difunctionalization of Donor-Acceptor Cyclopropanes Enabled by Copper Nitrate: A Direct Approach to γ-Halonitrates.

Organic Letters
1,3-Difunctionalization of donor-acceptor cyclopropanes with copper nitrate and N-halosuccinimide was developed to efficiently afford γ-halonitrates. The pivotal factor of this protocol lies in the dual role of copper nitrate as a Lewis acid and an ideal
Ruoxin Huang, Mingchun Gao, Zhenkun Yang, Wanghao Han, Ziqiang Wei, Zhen Li, Bin Xu   +6 more
semanticscholar   +1 more source

Diastereoselective (8+3)‐Cycloadditions of Donor‐Acceptor Cyclopropanes with Tropothione

Annalen der Pharmacie
Reactions of dimethyl 2‐arylcyclopropane‐1,1‐dicarboxylates, used as representatives of D‐A cyclopropanes, with tropothione were carried out in the presence of scandium triflate as a catalyst, under mild conditions (CH2Cl2 solution, rt). The anticipated (
G. Mlostoń, Mateusz Kowalczyk, Marcin Palusiak, Gwyndaf A. Oliver, Heinrich F. von Köller, D. Werz   +5 more
semanticscholar   +1 more source

Ytterbium Triflate-Catalyzed Intramolecular Arylative Ring Opening of Arylaminomethyl-Substituted Donor-Acceptor Cyclopropanes: Access to Tetrahydroquinolines.

Journal of Organic Chemistry
The treatment of arylaminomethyl-substituted donor-acceptor cyclopropanes with a catalytic amount of Yb(OTf)3 provides expedient access to tetrahydroquinoline derivatives.
Thangaraj Devaraj, K. Srinivasan
semanticscholar   +1 more source

Intramolecular 1,2-Aroyl Migration in Spiro Donor-Acceptor Cyclopropanes: Formation of 1,4-Naphthoquinones and 1-Naphthols as Ring-Expansion Products.

Journal of Organic Chemistry
Most of the known rearrangement reactions of donor-acceptor cyclopropanes (DACs) involve the migration of cationic carbon atom to anionic carbon or heteroatoms in 1,3- or 1,4-positions.
F. Daniel, K. Srinivasan
semanticscholar   +1 more source

1,3- and 1,2-Zwitterionic Complexes of Donor-Acceptor Cyclopropanes in Reactions with Arylallenes.

Chemistry
The reaction of 2-arylcyclopropane-1,1-dicarboxylates (ACDC) with GaCl3 and other Lewis acids in the presence of 3-arylbuta-1,2-dienes, which acts as a trapping agent for the 1,2- or 1,3-zwitterionic intermediates being generated, has been studied.
A. A. Ershova, Elizaveta A Ulchenko, D. Borisov, E. Budynina, R. A. Novikov, Y. Tomilov   +5 more
semanticscholar   +1 more source