104367-49-9Relevant academic research and scientific papers
Silica Support-Enhanced Pd-Catalyzed Allylation Using Allylic Alcohols
Motokura, Ken,Ikeda, Marika,Kim, Minjune,Nakajima, Kiyotaka,Kawashima, Sae,Nambo, Masayuki,Chun, Wang-Jae,Tanaka, Shinji
, p. 4536 - 4544 (2018)
Although allylation using allylic alcohol is an environmentally-friendly method because of water being the sole byproduct in such reactions, allylic alcohol is one of the most difficult allylating agents in Pd-catalyzed allylation of nucleophiles. In this study, we successfully developed a mesoporous silica-supported Pd complex as an efficient catalyst for the allylation of nucleophiles using allylic alcohols as allylating agents. The allylic alcohol is activated by the silanol group on the support surface, which easily undergoes a π-allylpalladium intermediate formation. The catalytic activity of the supported Pd complex was ca. 9 times higher than that of its homogeneous precursor Pd complex. A highest turnover number of 4500 based on Pd was achieved. Various nucleophiles and allylic alcohol derivatives could be used as substrates. Not only the detailed catalyst structure but also the reaction mechanism including the concerted activation of allylic alcohol by the Pd complex and silanol were investigated by several spectroscopic techniques, such as Pd K-edge XAFS, solid-state NMR, and in-situ FT-IR measurements.
Efficient and Clean Nickel Catalyzed α-Allylation Reaction of Nitriles
Mouhsine, Bouchaib,Karim, Abdallah,Dumont, Clément,Suisse, Isabelle,Sauthier, Mathieu
supporting information, p. 1457 - 1462 (2021/02/16)
A clean method has been developed for the α-allylation of phenyl and alpha alkyl phenyl acetonitrile with allylic alcohols. The reaction is catalyzed by nickel complexes in situ generated from a combination of Ni(cod)2 and the dppf ligand and performed at 80 °C in methanol as reaction solvent.Accordingly to this simple and base-free protocol that only yields water as a side-product, many allylic nitriles were synthetized with good yields. (Figure presented.).
Copper-Catalyzed Carbonylative Synthesis of β-Homoprolines from N-Fluoro-sulfonamides
Wu, Xiao-Feng,Yin, Zhiping,Zhang, Youcan
supporting information, p. 1889 - 1893 (2020/03/24)
A new methodology for the carbonylative transformation of N-fluoro-sulfonamides into N-sulfonyl-β-homoproline esters has been described. In the presence of a catalytic amount of Cu(OTf)2, a range of β-homoproline derivatives were prepared in moderate to good yield. The reaction proceeds via the intramolecular cyclization and intermolecular carbonylation of a free carbon radical. Notably, this procedure offers the possibility to build potential functionalized bioactive molecules.
Palladium(II)-Catalyzed Aminotrifluoromethoxylation of Alkenes: Mechanistic Insight into the Effect of N-Protecting Groups
Chen, Chaohuang,Chen, Pinhong,Hou, Chuanqi,Liu, Guosheng
supporting information, p. 346 - 350 (2020/05/25)
An efficient palladium-catalyzed regioselective 5-exo aminotrifluoromethoxylation of alkenes has been established herein, which provides a practical route towards the synthesis of OCF3-containing pyrrolidines. tert-Butyloxycarbonyl (Boc) as an amino protecting group plays a significant role in both the chemo- and regioselectivities. In addition, preliminary mechanistic studies reveal that the amino protecting group of substrates and the counter anion of palladium catalyst play critical roles in reaction efficiency presumably due to an isomerization of alkyl- Pd(II) intermediates. Moreover, the asymmetric 5-exo aminotrifluoromethoxylation reaction has also been achieved by introducing a sterically bulky pyridinyl-oxazoline ligand.
Pd-Catalyzed Intramolecular Aminoalkylation of Unactivated Alkenes: Access to Diverse N-Heterocycles
Ye, Liu,Lo, Kai-Yip,Gu, Qiangshuai,Yang, Dan
supporting information, p. 308 - 311 (2017/04/21)
A highly efficient palladium-catalyzed intramolecular aminoalkylation of unactivated alkenes in the absence of an external ligand and oxidant is described. New C-N and C(sp3)-C(sp3) bonds are formed simultaneously. This general transformation allows for construction of diverse N-heterocycles. Mechanistic studies show that the process may involve a four-membered Pd(alkyl)amido intermediate.
I2-Mediated oxidative bicyclization of 4-pentenamines to prolinol carbamates with CO2 incorporating oxyamination of the C=C bond
Wang, Sheng,Zhang, Xiaowei,Cao, Chengyao,Chen, Chao,Xi, Chanjuan
supporting information, p. 4515 - 4519 (2017/10/13)
A metal-free oxyamination reaction of alkenes with ambient CO2 is reported. In the presence of I2 and DBU, CO2 is applied in situ as a protecting group to regulate the nucleophilicity of the amino group and facilitate the bicyclization of 4-pentenamines with high chemoselectivity. Moreover, this reaction provided a feasible approach to prepare prolinol carbamates with good tolerance of functional groups and high efficiency under mild conditions.
Activation of alcohols with carbon dioxide: Intermolecular allylation of weakly acidic pronucleophiles
Lang, Simon B.,Locascio, Theresa M.,Tunge, Jon A.
supporting information, p. 4308 - 4311 (2014/11/08)
The direct coupling of allyl alcohols with nitroalkanes, nitriles, and aldehydes using catalytic Pd(PPh3)4 has been accomplished via activation of C-OH bonds with CO2. The in situ formation of carbonates from alcohols and CO2 facilitates oxidative addition to Pd to form reactive π-allylpalladium intermediates. In addition, the formation of a strong base activates nucleophiles toward the reaction with the π-allylpalladium electrophile. Overall, this atom economical reaction provides a new C-C bond without the use of an external base and generates water as the only byproduct.
Deacylative allylation: Allylic alkylation via retro-Claisen activation
Grenning, Alexander J.,Tunge, Jon A.
supporting information; experimental part, p. 14785 - 14794 (2011/11/04)
A new method for allylic alkylation of a variety of relatively nonstabilized carbon nucleophiles is described herein. In this process of "deacylative allylation", the coupling partners, an allylic alcohol and a ketone pronucleophile, undergo in situ retro-Claisen activation to generate an allylic acetate and a carbanion. In the presence of palladium, these reactive intermediates undergo catalytic coupling to form a new C-C bond. In comparison to unimolecular decarboxylative allylation, a commonly utilized method for allylation of carbon anions, deacylative allylation is an intermolecular process. Moreover, deacylative allylation allows the direct coupling of readily available allylic alcohols. Lastly, the full utility of deacylative allylation is demonstrated by the rapid construction of a variety 1,6-heptadienes via 3-component couplings.
Regiospecific decarboxylative allylation of nitriles
Recio III, Antonio,Tunge, Jon A.
supporting information; scheme or table, p. 5630 - 5633 (2010/03/02)
[Chemical Equation Presented] Palladium-catalyzed decarboxylative α-allylation of nitriles readily occurs with use of Pd2(dba) 3 and rac-BINAP. This catalyst mixture also allows the highly regiospecific α-allylation of nitriles in the presence of much more acidic α-protons. Thus, the reported method provides access to compounds that are not readily available via base-mediated allylation chemistries. Lastly, mechanistic investigations indicate that there is a competition between C- and N-allylation of an intermediate nitrile-stabilized anion and that N-allylation is followed by a rapid [3,3]-sigmatropic rearrangement.
Metalated nitriles: Organolithium, -magnesium? and -copper exchange of α-halonitriles
Fleming, Fraser F.,Zhang, Zhiyu,Liu, Wang,Knochel, Paul
, p. 2200 - 2205 (2007/10/03)
(Chemical Equation Presented) α-Halonitriles react with alkyllithium, organomagnesium, and lithium dimethylcuprate reagents generating reactive, metalated nitriles. The rapid halogen-metal exchange with alkyllithium and Grignard reagents allows selective exchange in the presence of reactive carbonyl electrophiles, including aldehydes, providing a high-yielding alkylation protocol. Lithiated and magnesiated nitriles react with propargyl bromide by SN2 displacement whereas organocopper nitriles react by S N2′ displacement, correlating with the formation of a C-metalated nitrile.
