14114-05-7Relevant articles and documents
[C^N]-Alkenyl Gold(III) Complexes by Proximal Ring-Opening of (2-Pyridyl)alkylidenecyclopropanes: Mechanistic Insights
González, Jorge A.,López, Fernando,Mascare?as, José Luis,Nevado, Cristina,Verdugo, Felipe
, p. 20049 - 20054 (2020)
Pyridine-substituted alkylidenecyclopropanes (Py-ACPs) react with gold(III) salts under mild reaction conditions through an unprecedented, proximal ring-opening pathway, to generate highly appealing, catalytically active pyridine alkenyl [C^N]-gold(III) species. Mechanistic studies reveal that the activation of the C?C bond of the ACP takes place through an unusual concerted, σ-bond metathesis type-process.
Reaction of Vinylphosphonium Salts with Sulfoxonium Ylides. Synthesis of Cyclopropylphosphonium Salts
Okuma, Kentaro,Ikari, Komei,Ono, Masaaki,Sato, Yasunari,Kuge, Seiji,et al.
, p. 2313 - 2318 (1995)
Reactions of (dimethylamino)phenylsulfoxonium mathylide with triphenylvinylphosphonium salts gave the corresponding cyclopropyltriphenylphosphonium salts (E-form) in high yields, when 1,8-diazabicycloundec-7-ene was used as a base.Reactions of cyclopropyltriphenylphosphonium salts with sodium hydride in the presence of trisamine afforded the corresponding ylides, which further reacted with aldehydes to give alkylidenepropanes in high yields.
Process for the Preparation of (3E, 7E)-Homofarnesol
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Paragraph 0095-0097, (2013/10/22)
The present invention relates to new types of processes for the improved preparation of homofarnesol, in particular of (3E,7E)-homofarnesol and homofarnesol preparations with an increased content of (3E,7E)-homofarnesol (also referred to as all E-homofarnesol).
Ni-catalyzed intramolecular cycloaddition of methylenecyclopropanes to alkynes
Yao, Bangben,Li, Yong,Liang, Zunjun,Zhang, Yuhong
supporting information; experimental part, p. 640 - 643 (2011/04/16)
Ni-catalyzed intramolecular cycloaddition of methylenecyclopropanes (MCPs) to arkylalkynes via proximal bond cleavage is reported. The reaction provides a facile route for the preparation of cyclopenta[a]indene derivatives.
Polylithiumorganic compounds -19. Regioselective carbon-carbon σ-bond scission followed by a 1,6-proton shift upon the reductive metalation of benzylidenecyclopropane derivatives with lithium metal
Maercker, Adalbert,Daub, Volker E. E.
, p. 2439 - 2458 (2007/10/02)
Depending on the substituent α-substituted benzylidenecyclopropanes (32) react more or less readily with lithium dust (2% sodium) in diethyl ether whereby a regioselective scission of only the cyclopropane σ-bond cis to the phenyl ring takes place. Upon raising the temperature the primarily formed 1,3-dilithiumorganic compound due to an agostic interaction rearranges by a 1,6-proton shift into a doubly bridged 1,4-dilithio compound. With α-methylbenzylidenecyclopropane (32c) this rearrangement was shown to occur intermolecularly via a trilithiumorganic compound 56. The suggested mechanism of these reductive metalation reactions via a bisected radical anion 87 where the lithium is mainly bound to the cyclopropyl carbon atom and oriented syn to the phenyl ring, was supported by MNDO (geometries) and ab initio (energies) calculations.
1,2-Hydrogen migration and alkene formation in the photoexcited states of alkylphenyldiazomethanes
?elebi, Sol,Leyva, Soccoro,Modarelli, David A.,Platz, Matthew S.
, p. 8613 - 8620 (2007/10/02)
Laser flash photolysis of alkylphenyldiazomethanes in the presence of pyridine produces easily detected ylides. The data indicate that photolysis of alkylphenyldiazomethanes leads to both carbene formation and direct formation of rearrangement products which do not derive from relaxed carbene intermediates.
On the Influence of Substituents on the Cope Rearrangement of 1,5-Hexadienes: Cyclopropyl- and Methyl-substituted Model Systems
Kaufmann, Dieter,Meijere, Armin de
, p. 1128 - 1138 (2007/10/02)
The new 1,5-hexadiene derivatives 1 and 2 are obtained along with all other conceivable products upon methylenation of 1,2,6,7-octatetraene (5); 2 is also accessible from succindialdehyde and cyclopropylidenetriphenylphosphorane.The thermal rearrangements of 1 and 2 both proceed like that of 5 in two steps via 1,4-cyclohexadiyls, 1 yielding 3 and 19, 2 only 4.The distinct differences in the gas phase kinetic parameters for 2 and 15 (ln k(2) = 22.0-26200/RT and ln k(15) = 29.1-33300/RT, respectively) indicate the change in mechanism of the Cope rearrangement from concerted (for 15) to stepwise (for 2), apparently due to the cyclopropyl substituent effects.Upon sensitized irradiation of 2 the new hydrocarbons 24, 25, and 27 are formed, whereas nickel(0)-catalyzed rearrangement of 2 yields 25 exclusively.
