Results 111 to 120 of about 83,038 (344)

A concise enantioselective synthesis of the guaiane sesquiterpene (−)-oxyphyllol

Beilstein Journal of Organic Chemistry, 2013
(−)-Oxyphyllol was prepared in only 4 steps from an epoxy enone that already served as an intermediate for the total synthesis of the anticancer guaiane (−)-englerin A.
Martin Zahel, Peter Metz
doaj   +1 more source

Diastereoselective Synthesis of Spirocyclopropanes under Mild Conditions via Formal [2 + 1] Cycloadditions Using 2,3-Dioxo-4-benzylidene-pyrrolidines

Molecules, 2017
A highly diastereoselective cyclopropanation of cyclic enones with sulfur ylides was developed under catalyst-free conditions, producing multifunctional spirocyclopropanes in generally excellent yields (up to 99% yield and >99:1 d.r.).
Yi Li, Qing-Zhu Li, Li Huang, Hong Liang, Kai-Chuan Yang, Hai-Jun Leng, Yue Liu, Xu-Dong Shen, Xiao-Jun Gou, Jun-Long Li   +9 more
doaj   +1 more source

Towards energetically viable asymmetric deprotonations : selectivity at more elevated temperatures with C2-symmetric magnesium bisamides [PDF]

, 2011
A novel chiral magnesium bisamide has enabled the development of effective asymmetric deprotonation protocols at substantially more elevated temperatures.
Aggarwal, Alexakis, Allan, Allan J. B. Watson, Anderson, Aoki, Aoki, Aoki, Aoki, Bassindale, Blümke, Brownbridge, Brownbridge, Bunn, Bunn, Bunn, Busch-Petersen, Carswell, Clegg, Conway, Corey, Cousins, Eaton, Eaton, Graf, Graf, Gronnow, Hama, Henderson, Henderson, Henderson, Henderson, Henderson, Hodgson, Ila, Kerr, Kerr, Kerr, Knochel, Leitner, Linsey S. Bennie, Melzig, Michael Middleditch, Mulvey, Navarro, Netherton, Sato, Shirai, Shirai, Simpkins, Simpkins, Westerhausen, William J. Kerr, Wunderlich, Çalimsiz   +54 more
core   +1 more source

Easier, Safer, and Greener: Unlocking the Power of Solid Reagents in Organic Reactions by Mechanochemistry

ChemistryEurope, EarlyView.
This review highlights the powerful synergy between mechanochemistry and solid reagents to replace hazardous substances traditionally used in organic synthesis. Such an approach offers a safer and more sustainable pathway for conducting organic reactions, with potential benefits in both reactivity and selectivity. The use of solid bases, acids, and gas
Adrien Gallego, Nicolas Pétry, Julien Pinaud, Olivia Giani, Frédéric Lamaty   +4 more
wiley   +1 more source

Formal Synthesis of (±)-Coriolin by Diastereocontrolled Nickel(0)-Catalyzed 'Metallo-ene-type' Cyclization/Methoxycarbonylation

CHIMIA, 1992
Bicyclooctanone (±)-2, an advanced intermediate for the synthesis of (±)-coriolin, has been synthesized in ten steps starting from 2,2-dimethylpent-4-enal (7). The key step 6 ?
Wolfgang Oppolzer, Akira Ando
doaj   +2 more sources

Concise total synthesis of (+)-bionectins A and C [PDF]

, 2013
The concise and efficient total synthesis of (+)-bionectins A and C is described. Our approach to these natural products features a new and scalable method for erythro-β-hydroxytryptophan amino acid synthesis, an intramolecular Friedel–Crafts reaction of
Adams, Timothy C., Coste, Alexis, Kim, Justin, Movassaghi, Mohammad   +3 more
core   +1 more source

Synthesis of α‐Pentafluorosulfanylated‐β2,3‐Amino Esters

ChemistryEurope, EarlyView.
De novo α‐SF5‐β2,3‐amino esters are now accessible through a straightforward aza‐Michael reaction using a series of newly developed (E)‐α‐SF5‐α,β‐unsaturated esters. Two new, highly functionalized, contiguous tertiary stereocenters are formed with diastereodivergence governed by the choice of solvent and/or base.
Thi Mo Nguyen, Guilhem Colomer, Oscar Maugue‐Sauze, Nicolas Blanchard, Vincent Bizet, Dominique Cahard   +5 more
wiley   +1 more source

CuH‐Catalyzed Asymmetric Desymmetrization of Cyclobutenes via Stereodivergent Hydroamination

ChemistryEurope, EarlyView.
The CuH‐catalyzed stereodivergent hydroamination through asymmetric desymmetrization of cyclobutenes has been achieved, yielding a range of trisubstituted aminocyclobutanes with excellent results. A series of subsequent transformations, including the first asymmetric synthesis of two pharmaceutically active molecules, have been realized, and density ...
Xiang Lei, Peng Luo, Shouang Lan, Wennan Dong, Chao Xu, Jinggong Liu, Shuang Yang, Qi Zhang, Xinqiang Fang   +8 more
wiley   +1 more source

Total Synthesis and Complete Stereochemical Assignment of Amphirionin‐5, a Potent Natural Osteoblasts Proliferator

ChemistryEurope, EarlyView.
The convergent total synthesis of a candidate diastereomer of amphirionin‐5 was accomplished in 22 steps via the coupling of the C1‐C16 enone segment and the C17‐C28 aldehyde segment using Stetter reaction. The overall stereochemistry of amphirionin‐5 was fully assigned, based on the comparison of spectroscopic and chiroptical data between the ...
Yusuke Ogura, Kenji Nemoto, Tadafumi Fujita, Yuta Inori, Daisuke Abe, Hironori Okamura, Hirosato Takikawa, Shigefumi Kuwahara   +7 more
wiley   +1 more source

Scope and mechanism of the highly stereoselective metal-mediated domino aldol reactions of enolates with aldehydes

Beilstein Journal of Organic Chemistry, 2016
A one-pot transformation, which involves the reaction of ketones with aldehydes in the presence of metal halides to furnish tetrahydro-2H-pyran-2,4-diols in a highly diastereoselective manner, is investigated thoroughly by experiments and computations ...
M. Emin Cinar, Bernward Engelen, Martin Panthöfer, Hans-Jörg Deiseroth, Jens Schlirf, Michael Schmittel   +5 more
doaj   +1 more source