Results 31 to 40 of about 5,806 (187)

Access to cyclopropanes with geminal trifluoromethyl and difluoromethylphosphonate groups

Beilstein Journal of Organic Chemistry, 2023
A synthetic route to the bench-stable fluorinated masked carbene reagent diethyl 2-diazo-1,1,3,3,3-pentafluoropropylphosphonate, bearing a trifluoromethyl and a difluoromethyl group is reported for the first time.
Ita Hajdin, Romana Pajkert, Mira Keßler, Jianlin Han, Haibo Mei, Gerd-Volker Röschenthaler   +5 more
doaj   +1 more source

Biosynthesis of the Fully Saturated C16 Homosesquiterpene Descartane Through Deprotonation With Cyclopropanation

Angewandte Chemie International Edition, EarlyView.
A non‐canonical C16 sesquiterpene synthase from Morganella morganii produces the unusual scaffold descartane. Its cyclisation mechanism was rationalised by isotopic labelling experiments and DFT calculations. Site‐directed mutagenesis altered enzyme function, resulting in alternative products, including voltairene, which requires a different ...
Kexin Yang, Philip Troycke, Bernd Goldfuss, Michael Groll, Jeroen S. Dickschat   +4 more
wiley   +1 more source

Transforming cyclopropanes to enamides via σ-C–C bond eliminative borylation

Nature Communications
Recent strides in C–H borylation have significantly expanded our toolkit for the preparation of organoboronates. Nevertheless, avenues alternative to obtain these compounds via σ-C–C cleavage, thereby facilitating molecular scaffold editing, remain ...
Shuyu Kang, Jiahang Lv, Tianhang Wang, Bingcheng Wu, Minyan Wang, Zhuangzhi Shi   +5 more
doaj   +1 more source

Photogenerated Oxetanes as a Gateway to Uphill Cyclopropanation

Angewandte Chemie International Edition, EarlyView.
An atom‐economical route to densely functionalized cyclopropanes from furans and photochemically activated aldehydes is enabled by a unique oxetane‐to‐cyclopropane rearrangement. These cyclopropanes can be used to access complex bioactive scaffolds and serve as a platform for asymmetric cyclopropane synthesis.
Tim Köglmeier, Thomas J. Tiefel, Oliver Reiser   +2 more
wiley   +1 more source

Dirhodium(II)-catalyzed [3 + 2] cycloaddition of N-arylaminocyclopropane with alkyne derivatives

Beilstein Journal of Organic Chemistry, 2019
Dirhodium(II) complex-catalyzed [3 + 2] reactions between N-arylaminocyclopropanes and alkyne derivatives are described. The cycloaddition products proved to be versatile synthetic intermediates.
Wentong Liu, Yi Kuang, Zhifan Wang, Jin Zhu, Yuanhua Wang   +4 more
doaj   +1 more source

Scalable synthesis of (1-cyclopropyl)cyclopropylamine hydrochloride

Beilstein Journal of Organic Chemistry, 2011
1-Cyclopropylcyclopropanecarboxylic acid (2), which is accessible on a large scale (900 mmol) from 1-bromo-1-cyclopropylcyclopropane (1) in 64% yield (89% on a 12.4 mmol scale), has been subjected to a Curtius degradation employing the Weinstock protocol
Sergei I. Kozhushkov, Alexander F. Khlebnikov, Rafael R. Kostikov, Dmitrii S. Yufit, Armin de Meijere   +4 more
doaj   +1 more source

Catalytic Generation of Cationic Gold Carbene Complexes From 7‐Alkynylnorbornadienes and Their Intermolecular Cyclopropanation With Alkenes

Chemistry – A European Journal, EarlyView.
Efficient cationic gold(I)‐catalyzed intermolecular cyclopropanation of 7‐alkynylnorbornadiene derivatives has been developed. This methodology offers the synthesis of a new class of norbornene derivatives in high yield with excellent diastereoselectivity.
Kento Ishida, Kenta Toei, Fumiaki Tomi, Norio Sakai   +3 more
wiley   +1 more source

(2R,1'S,2'R)- and (2S,1'S,2'R)-3-[2-Mono(di,tri)fluoromethylcyclopropyl]alanines and their incorporation into hormaomycin analogues

Beilstein Journal of Organic Chemistry, 2014
Efficient and scalable syntheses of enantiomerically pure (2R,1'S,2'R)- and (2S,1'S,2'R)-3-[2-mono(di,tri)fluoromethylcyclopropyl]alanines 9a–c, as well as allo-D-threonine (4) and (2S,3R)-β-methylphenylalanine (3), using the Belokon' approach with (S ...
Armin de Meijere, Sergei I. Kozhushkov, Dmitrii S. Yufit, Christian Grosse, Marcel Kaiser, Vitaly A. Raev   +5 more
doaj   +1 more source

Studien zur Biidung von Cyclopropan- und Oxiran-Derivaten in der Dreikomponentenreaktion von Basen, α-Halogen-acrylsäure-derivaten und Carbonylverbindungen

CHIMIA, 1975
The competitive formation of oxiranes 1 and cyclopropanes 2 in the reaction of 2-halogeno-acrylic acid-derivatives, carbonyl-compounds and bases is discussed.
R. Scheffold, P. Bissig, K.L. Ghatak, B. Granwehr, B. Patwardhan   +4 more
doaj   +1 more source

Oxidative Generation and Reactivity of the Cyclopropyl Radical From a Martin Silicate

Chemistry – A European Journal, EarlyView.
A photoredox strategy employing Martin silicates enables the oxidative generation and controlled capture of cyclopropyl radicals, including the naked one, long considered challenging intermediates. The method affords functionalized cyclopropanes through both Giese‐type additions and dual nickel/photoredox C(sp3)−C(sp2) cross‐couplings.
Amal Lakhal, Alexandre Millanvois, Louis Fensterbank, Cyril Ollivier   +3 more
wiley   +1 more source