Results 81 to 90 of about 19,882 (280)

A unique Pd-catalysed Heck arylation as a remote trigger for cyclopropane selective ring-opening

Nature Communications, 2017
Functionalizing multiple, distant sites across a molecule is a challenge. Here the authors report a remote functionalization strategy, whereby an initial Heck reaction leads to chain-walking of palladium across a molecule, ring-opening cyclopropanes ...
Sukhdev Singh, Jeffrey Bruffaerts, Alexandre Vasseur, Ilan Marek   +3 more
doaj   +1 more source

Copper-catalyzed diastereo- and enantioselective desymmetrization of cyclopropenes: Synthesis of cyclopropylboronates [PDF]

, 2014
This document is the accepted manuscript version of a Published Work that appeared in final form in Journal of American Chemical Society 136.45, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the
Alejandro Parra, Alfaro R., Aurora López, Berman A. M., Bonet A., Bonet A., Carroll A. M., Chen D. Y.-K., Chen H., Corberán R., Crudden C. M., Didier D., Donaldson W. A., Doucet H., Fox J. M., Fujioka Y., He C., Imai T., Ito H., José Luis García Ruano, Krämer K., Laura Amenós, Lee K.-s., Lee Y., Liao L., Liskey C. W., Liu H., Liu X., Lohr S., Luithle J. E. A., Manuel Guisán-Ceinos, Marek I., Mariola Tortosa, Markó I. E., Masarwa A., Matsuda N., Matsuda N., Matteson D. S., Miki Y., Mun S., Nakamura M., Nakamura M., Noh D., Noh D., Phan D. H. T., Pietruszka J., Pietruszka J., Pietruszka J., Priestley E. S., Rubin M., Rubin M., Rubina M., Rubina M., Rucker R. P., Sakae R., Sherrill W. M., Simaan S., Simaan S., Tarwade V., Tortosa M., Utimoto K., Wessjohann L. A., Wu H., Yang Z., Yoo E. J., Zhong C., Zhou S.-M., Zhu S.   +67 more
core   +2 more sources

Sulfur‐Mediated Ring‐Opening Cyclization of Spirocyclopropanes for the Construction of Benzo[b]thiophene Skeleton

Chemistry – An Asian Journal, EarlyView.
Regioselective ring‐opening cyclization of spirocyclopropanes with NaSH proceeded smoothly, and subsequent addition of an acid afforded tetrahydrobenzo[b]thiophen‐4‐ones that could be converted into the 4‐hydroxybenzo[b]thiophenes. This protocol provides an alternative synthetic method to access benzo[b]thiophenes without using multisubstituted ...
Hisanori Nambu, Yuki Seto, Yuta Onuki, Koga Yamazaki, Keisuke Tomohara, Takayuki Yakura   +5 more
wiley   +1 more source

Synthesis of organic liquid crystals containing selectively fluorinated cyclopropanes

Beilstein Journal of Organic Chemistry, 2020
This paper describes the synthesis of a series of organic liquid crystals (LCs) containing selectively fluorinated cyclopropanes at their termini. The syntheses used difluorocarbene additions to olefin precursors, an approach which proved straightforward
Zeguo Fang, Nawaf Al-Maharik, Peer Kirsch, Matthias Bremer, Alexandra M. Z. Slawin, David O’Hagan   +5 more
doaj   +1 more source

Using Semantic Technologies in Digital Libraries- A Roadmap to Quality Evaluation [PDF]

, 2009
. In digital libraries semantic techniques are often deployed to reduce the expensive manual overhead for indexing documents, maintaining metadata, or caching for future search.
A. Hotho, D. Vrandečić, H. Halpin, J. Diederich, K. Bischoff, K. Razikin, M. Sanderson, N. Fuhr, P. Cimiano, R. Krestel, S. Bao, S. Chan, S.R. Kruk   +12 more
core   +2 more sources

Visible Light‐Mediated Preparation of a Key Intermediate Employed in the Synthesis of Zolpidem and Several Analogs

Chemistry – An Asian Journal, EarlyView.
A new visible light‐induced method is reported for the C3‐alkylation of imidazo[1,2‐a]pyrimidines and ‐pyridines with aryldiazoacetates. This protocol can be performed in open air and serves as a convenient entry to several known and new molecules. A formal synthesis of zolpidem is achieved by changing the alkylating agent to an appropriate hypervalent
Ronei M. S. Souza, Tales A. C. Goulart, Roberto do C. Pinheiro, Felipe F. do C. Sonaglio, Deborah de A. Simoni, Rodrigo A. Cormanich, Igor D. Jurberg   +6 more
wiley   +1 more source

Stereoselective Lewis Acid Mediated (3+2) Cycloadditions of N-H- and N-Sulfonylaziridines with Heterocumulenes [PDF]

, 2014
Alkyl and aryl isothiocyanates and carbodiimides are effective substrates in (3+2) cycloadditions with N-sulfonyl-2-substituted aziridines and 2-phenylaziridine for the synthesis of iminothiazolidines and iminoimidazolidines.
Craig, Robert A., II, Goldberg, Alexander F. G., O'Connor, Nicholas R., Stoltz, Brian M.   +3 more
core   +2 more sources

First Row Transition Metals in Olefin Metathesis: The Role of Iron and Manganese

ChemCatChem, EarlyView.
Olefin metathesis is primarily a love story with molybdenum and ruthenium, but the dream is to transition to first‐row transition metals, such as manganese and especially iron. Will this be feasible? This work discusses some challenges associated with this migration.
Artur Brotons Rufes, Juan Pablo Martínez, Nicolas Joly, Sylvain Gaillard, Jean Luc Renaud, Sergio Posada Pérez, Albert Poater   +6 more
wiley   +1 more source

Borane catalysed ring opening and closing cascades of furans leading to silicon functionalized synthetic intermediates

Nature Communications, 2016
Furans are attractive staring materials in organic chemistry, due to the ease of functionalisation and sourcing from renewable feedstocks. Here the authors show the ring opening of furans to silane intermediates, followed by further conversion to ...
Chinmoy K. Hazra, Narasimhulu Gandhamsetty, Sehoon Park, Sukbok Chang   +3 more
doaj   +1 more source

Asymmetric one-pot synthesis of cyclopropanes

Macedonian Journal of Chemistry and Chemical Engineering, 2016
Cycloaddition of the diazoalkanes to electron-deficient olefins (in situ) affords polysubstituted cyclopropanes in high yields (up to 85%). Deprotection of the ketal protecting group provided water-soluble cyclopropane-bearing carbohydrate in good yields.
Naoufel Ben Hamadi, Ahlem Guesmi, Wided Nouira   +2 more
doaj   +1 more source