Results 61 to 70 of about 21,746 (290)

Olefin Cyclopropanation via Carbene Transfer Catalyzed by Engineered Cytochrome P450 Enzymes [PDF]

, 2013
Transition metal–catalyzed transfers of carbenes, nitrenes, and oxenes are powerful methods for functionalizing C=C and C–H bonds. Nature has evolved a diverse toolbox for oxene transfers, as exemplified by the myriad monooxygenation reactions catalyzed ...
Arnold, Frances H., Brustad, Eric M., Coelho, Pedro S., Kannan, Arvind   +3 more
core  

Cyclopropyl and cyclobutylboronates and silanes: A stereo­selective approach [PDF]

, 2018
Chiral cyclopropyl- and cyclobutylboronic esters and -silanes have become attractive intermediates for the preparation of functionalized small rings.
Martín-Heras, Víctor, Parra, Alejandro, Tortosa Manzanares, Mariola   +2 more
core   +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

2-Diazoacetoacetic acid, an efficient and convenient reagent for the synthesis of alpha-diazo-beta-ketoesters [PDF]

, 2006
The formation of various alpha-diazo acetoacetic esters can be obtained in a single transformation with good to excellent yields using readily available 2-diazoacetoacetic ...
Ferreira, Eric M., Meyer, Michael E., Stoltz, Brian M.   +2 more
core  

Efficient preparation of TMSCCl2Br and its use in dichlorocyclopropanation of electron deficient alkenes [PDF]

, 2016
The reaction of excess TMSCl and LiCCl2Br at low temperature is a technically simple high yield route to TMSCCl2Br. The latter is a stable source of the dichlorobromomethide carbanion, which undergoes 1,4-addition with cyclic nitroalkenes and (E ...
Burroughs, Laurence, Durán-Peña, Maria Jesus, Lee, Darren S., Woodward, Simon   +3 more
core   +1 more source

Total synthesis of avenaol

Nature Communications, 2017
Avenaol is a potent germination stimulant that can be extracted from black oat. Here, the authors report the total synthesis of avenaol by developing a strategy to access all-cis-substituted cyclopropanes.
Motohiro Yasui, Rina Ota, Chihiro Tsukano, Yoshiji Takemoto   +3 more
doaj   +1 more source

Atom Transfer Radical Reactions as a Tool for Olefin Functionalization : On the Way to Practical Applications [PDF]

, 2011
Transition-metal-catalyzed atom transfer radical reactions of halogenated compounds with olefins constitute a versatile tool in organic synthesis within the area of C–C bond forming transformations.
Muñoz Molina, José María, Pérez Romero, Pedro José, Rodríguez Belderraín, Tomás   +2 more
core   +1 more source

Introducing the Cis‐2,3‐Bis(trifluoromethyl)cyclopropyl Chemotype: Late‐Stage Installation and Stereoelectronic Properties

ChemistryEurope, EarlyView.
The cis‐2,3‐bis(trifluoromethyl)cyclopropyl chemotype is introduced. The steric demand of this motif is intermediate between that of the heptafluoroisopropyl and prefluorotertbutyl groups; yet, it induces significantly less lipophilicity than these due to its facial polarity.
Daniel Gaviña, Zeyu Feng, David Herrero, Martin Simon, Christopher Golz, Manuel Alcarazo   +5 more
wiley   +1 more source

Diastereo- and enantioselective [3 + 3] cycloaddition of spirocyclopropyl oxindoles using both aldonitrones and ketonitrones

Nature Communications, 2017
Chiral spirocyclic compounds are important structural motifs for drug discovery. Here, the authors report a synthetic route to spirocycles based on enantioselective cycloaddition of activated spirocyclopropyl oxindoles, which act as donor-acceptor ...
Peng-Wei Xu, Jia-Kuan Liu, Lan Shen, Zhong-Yan Cao, Xiao-Li Zhao, Jun Yan, Jian Zhou   +6 more
doaj   +1 more source

Enantioselective Total Synthesis of (+)-Salvileucalin B [PDF]

, 2011
An enantioselective total synthesis of the diterpenoid natural product (+)-salvileucalin B is reported. Key findings include a copper-catalyzed arene cyclopropanation reaction to provide the unusual norcaradiene core and a reversible retro ...
Levin, Sergiy, Nani, Roger R., Reisman, Sarah E.   +2 more
core   +1 more source