19714-73-9Relevant articles and documents
Regioselective Metalation of Phenylcyclopropane and Smooth Addition of 1-Phenylcyclopropyl Potassium onto Ethylene
Schlosser, Manfred,Schneider, Philippe
, p. 2404 - 2410 (1980)
Whereas pentyl sodium in pentane mainly promotes a hydrogen/metal exchange reaction at the m- and p-position of phenylcyclopropane, both the butyllithium/potassium t-butoxide reagent and trimethylsilylmethyl potassium in tetrahydrofuran convert phenylcyclopropane exclusively into 1-phenylcyclopropyl potassium.The latter organometallic derivative adds smoothly onto the double bond of ethylene at temperatures around -40 deg.
Silylium-Ion-Promoted Ring-Opening Hydrosilylation and Disilylation of Unactivated Cyclopropanes
Bonetti, Vittorio,Klare, Hendrik F. T.,Oestreich, Martin,Roy, Avijit,Wang, Guoqiang,Wu, Qian
supporting information, (2020/02/04)
A silylium-ion-promoted ring-opening hydrosilylation of unactivated cyclopropanes is reported. The reaction is facilitated by the γ-silicon effect, and the regioselectivity is influenced by various stabilizing effects on the carbenium-ion intermediates, including the β-silicon effect. The experimental observations are in accord with the computed reaction mechanism. The work also showcases the ability of silylium ions to isomerize cyclopropyl to allyl groups, and the resulting α-olefins engage in a silylium-ion-mediated disilylation with hexamethyldisilane.
Lewis Base-Promoted Ring-Opening 1,3-Dioxygenation of Unactivated Cyclopropanes Using a Hypervalent Iodine Reagent
Gieuw, Matthew H.,Ke, Zhihai,Yeung, Ying-Yeung
supporting information, p. 3782 - 3786 (2018/03/13)
A facile and effective system has been developed for the regio- and chemoselective ring-opening/electrophilic functionalization of cyclopropanes through C?C bond activation by [bis(trifluoroacetoxy)iodo]benzene with the aid of the Lewis basic promoter p-toluenesulfonamide. The p-toluenesulfonamide-promoted system works well for a wide range of cyclopropanes, resulting in the formation of 1,3-diol products in good yields and regioselectivity.
Aminofluorination of Cyclopropanes: A Multifold Approach through a Common, Catalytically Generated Intermediate
Pitts, Cody Ross,Ling, Bill,Snyder, Joshua A.,Bragg, Arthur E.,Lectka, Thomas
supporting information, p. 6598 - 6609 (2016/06/09)
We have discovered a highly regioselective aminofluorination of cyclopropanes. Remarkably, four unique sets of conditions-two photochemical, two purely chemical-generated the same aminofluorinated adducts in good to excellent yields. The multiple, diverse ways in which the reaction could be initiated provided valuable clues that led to the proposal of a "unifying" chain propagation mechanism beyond initiation, tied by a common intermediate. In all, the proposed mechanism herein is substantiated by product distribution studies, kinetic analyses, LFERs, Rehm-Weller estimations of ΔGET, competition experiments, KIEs, fluorescence data, and DFT calculations. From a more physical standpoint, transient-absorption experiments have allowed direct spectroscopic observation of radical ion intermediates (previously only postulated or probed indirectly in photochemical fluorination systems) and, consequently, have provided kinetic support for chain propagation. Lastly, calculations suggest that solvent may play an important role in the cyclopropane ring-opening step.
IMPROVEMENTS IN OR RELATING TO ORGANIC COMPOUNDS
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Page/Page column 19-20; 25; 26-27, (2015/05/06)
A process of converting a carbon-carbon multiple bond to a cyclopropane ring, comprising the addition of a N-alkyl-N-nitroso compound to a mixture of alkene precursor, aqueous base and Pd(II)-catalyst, with the N-alkyl-N-nitroso compound obtained directly from an alkyl amine derivative, NaNO2 and an acid via phase separation of the N-alkyl-N-nitroso compound from the aqueous phase.
Diels-Alder reactions for the construction of cyclopropylarenes
Arndt, Marion,Hilt, Gerhard,Khlebnikov, Alexander F.,Kozhushkov, Sergei I.,De Meijere, Armin
experimental part, p. 3112 - 3121 (2012/07/14)
The straightforward synthesis of new bicyclopropyl-substituted alkynes and 1,3-dienes and their application in cobalt-catalyzed Diels-Alder reactions are described. The cycloaddition processes generated the desired bicyclopropyl-substituted arene derivatives in moderate to good yields, depending on the steric congestion of the reaction partners. The regioselectivity of the cycloaddition was controlled by the ligand coordinated to the cobalt center. The cyclopropyl moiety remained unchanged over the course of the Diels-Alder reaction, indicating that no radical type intermediates were formed. Only in a single case did the DDQ oxidation of the primarily formed dihydroaromatic product lead to ring opening of a cyclopropyl subunit. In all of the other cases, cyclopropyl-modified arenes with various functionalities were obtained. Copyright
Indium-mediated, highly efficient cyclopropanation of olefins using CH 2I2 as methylene transfer reagent
Virender,Jain, Suman L.,Sain, Bir
, p. 37 - 38 (2007/10/03)
The indium-mediated, one-pot cyclopropanation of a variety of olefins with methylene iodide proceeds smoothly with excellent yields of products.
Aryl and vinyl cyclopropanes through the in situ generation of B- cyclopropyl-9-BBN and its Suzuki-Miyaura coupling
Soderquist, John A.,Huertas, Ramon,Leon-Colon, Gisela
, p. 4251 - 4255 (2007/10/03)
Dihydroboration of propargyl bromide with 9-BBN-H followed by treatment of the adduct with aqueous sodium hydroxide affords the hydroxy(cycloropropyl)borate complex (1), which undergoes efficient palladium-catalyzed cross-coupling to produce a variety of aryl and vinyl cyclopropanes (2) in good to excellent yields. (C) Elsevier Science Ltd.
