Results 31 to 40 of about 19,882 (280)

Catalytic cyclopropanation of polybutadienes [PDF]

Journal of Polymer Science Part A: Polymer Chemistry, 2010
AbstractCatalytic cyclopropanation of commercial 1,2‐ or 1,4‐cis‐polybutadiene, respectively, with ethyl diazoacetate catalyzed by [TpBr3Cu(NCMe)] (TpBr3 = hydrotris(3,4,5‐tribromo‐1‐pyrazolyl)borate) at room temperature afforded high molecular weight (Mn > 105 mol−1) side‐chain or main‐chain, respectively, carboxyethyl cyclopropyl‐substituted ...
Urbano Baena, Juan, Korthals, Brigitte, Díaz Requejo, María Mar, Pérez Romero, Pedro José, Mecking, Stefan   +4 more
openaire   +4 more sources

Shaping of a Reactive Manganese Catalyst Enables Access to Polyfunctionalized Cyclohexanes via Enantioselective C(sp3)─H Bond Oxidation of 1,3‐meso Diethers

Angewandte Chemie, EarlyView.
Structural shaping of a highly reactive chiral Mn‐oxo species translates into exceptionally enantioselective C─H oxidation catalyst of cyclohexyl 1,3‐meso diethers (up to >99% ee) leading to polyfunctionalized cyclohexanes. Abstract Chiral polyoxygenated cyclohexanes are valuable constituents of biologically relevant products.
Andrea Palone, Arnau Call, Aleria Garcia‐Roca, Josep M. Luis, Matthew S. Sigman, Massimo Bietti, Cristina Nevado, Miquel Costas   +7 more
wiley   +2 more sources

Development of a Vinylated Cyclic Allene: A Fleeting Strained Diene for the Diels–Alder Reaction

Angewandte Chemie, EarlyView.
A strain‐promoted Diels–Alder reaction of the vinylated cyclic allene, a highly reactive strained all‐carbon diene, was developed. Activation of the Kobayashi‐type precursor with fluoride ion generated the vinyl cyclic allene, which was trapped by dienophiles to produce decalin derivatives under mild conditions.
Haruki Mizoguchi, Takumi Obata, Taiki Hirai, Manaka Komatsu, Akira Sakakura   +4 more
wiley   +2 more sources

Asymmetric Titanium-Catalyzed Cyclopropanation of Nitriles with Grignard Reagents

SynOpen, 2018
The titanium-catalyzed asymmetric cyclopropanation of cyanoesters­ with Grignard reagents was investigated for the first time. Particularly, the study of the efficiency of Taddol-based titanium complexes­ has shown that the prior preparation of Taddol ...
Julien Caillé, Paul Setzer, Fabien Boeda, Morwenna S. M. Pearson-Long, Philippe Bertus   +4 more
doaj   +1 more source

Visible-light photocatalytic intramolecular cyclopropane ring expansion [PDF]

, 2017
Described herein is a new visible-light photocatalytic strategy for the synthesis of enantioenriched dihydrofurans and cyclopentenes by an intramolecular nitro cyclopropane ring expansion reaction.
Amador, Bai, Barton, Blum, Borisov, Brand, Cavitt, Cheng, Demissie, Garve, Ivanova, Kaur, Luis-Barrera, Marenich, Narayanam, Prier, Romero, Sabbatani, Schneider, Schneider, Vesely, von Dreele, Wang, Xu, Yamaguchi, Zhang, Zhao, Zhu   +27 more
core   +2 more sources

Reactivity of electrophilic cyclopropanes

Pure and Applied Chemistry, 2023
Abstract Cyclopropanes that carry an electron-accepting group react as electrophiles in polar, ring-opening reactions. Analogous reactions at cyclopropanes with additional C2 substituents allow one to access difunctionalized products. Consequently, functionalized cyclopropanes are frequently used building blocks in organic synthesis. The
Eitzinger, Andreas, Ofial, Armin R.
openaire   +3 more sources

Trigonal Planar Bis(carbene)Cu(I) Complexes Enable Divergent H2 Activation with H2O for Accelerated Olefin Hydrogenation

Angewandte Chemie, EarlyView.
Trigonal planar naphthyridine‐bis(carbene)Cu(I) alkyl, hydroxide, and ethoxide complexes promote a divergent mechanism of H2 activation for the rare catalytic hydrogenation of unactivated alkenes at mild conditions at copper. Abstract CuH‐catalyzed olefin hydrogenation is rare compared to those of carbonyl‐derived substrates. Olefin insertion into Cu–H
Evan A. Patrick, Shaama Mallikarjun Sharada, Anya Zoraster, Jeremy D. Erickson, David E. Ryan, R. Morris Bullock, Ba L. Tran   +6 more
wiley   +2 more sources

Cyclopropanation using flow-generated diazo compounds. [PDF]

, 2015
We have devised a room temperature process for the cyclopropanation of electron-poor olefins using unstabilised diazo compounds, generated under continuous flow conditions.
Battilocchio, Claudio, Hawkins, Joel M, Ingham, Richard J, Labes, Ricardo, Ley, Steven V, Roda, Nuria M, Tran, Duc N   +6 more
core   +2 more sources

Synthesis of skeletally diverse alkaloid-like molecules: exploitation of metathesis substrates assembled from triplets of building blocks

Beilstein Journal of Organic Chemistry, 2013
A range of metathesis substrates was assembled from triplets of unsaturated building blocks. The approach involved the iterative attachment of a propagating and a terminating building block to a fluorous-tagged initiating building block.
Sushil K. Maurya, Mark Dow, Stuart Warriner, Adam Nelson   +3 more
doaj   +1 more source

The Synthesis of Functionalized Dimethylphosphinoyl Cyclopropanes and Cyclobutanes

Журнал органічної та фармацевтичної хімії, 2023
A simple preparative approach to a series of functionalized dimethylphosphinoyl-containing cyclopropanes and cyclobutanes has been developed; it is based on cyclocondensation of dimethylphosphinoyl acetonitrile with 1,2- and 1,3-dibromoalkanes. Synthetic
Anastasiia M. Aleksandrova, Alona S. Cherednichenko, Yuliya V. Rassukana   +2 more
doaj   +1 more source