97455-11-3Relevant academic research and scientific papers
Photoinduced copper-catalyzed dual decarboxylative coupling of α,β-unsaturated carboxylic acids with redox-active esters
Lu, Xiao-Yu,Gao, Ang,Liu, Qi-Le,Xia, Ze-Jie
supporting information, (2021/06/15)
The first photoinduced copper-catalyzed dual decarboxylative cross-coupling of α,β-unsaturated carboxylic acids and redox-active esters has been developed. This reaction enabled C(sp2)–C(sp3) bond formation, which afforded a variety of synthetically valuable alkene derivatives. Many α,β-unsaturated carboxylic acids and redox-active ester derivatives were tolerant to this reaction. The reaction also tolerated many common functional groups.
Alkene homologation: via visible light promoted hydrophosphination using triphenylphosphonium triflate
Levin, Vitalij V.,Dilman, Alexander D.
supporting information, p. 749 - 752 (2021/02/03)
A hydrophosphination reaction of alkenes with triphenylphosphonium triflate under photocatalytic conditions is described. The reaction is promoted by naphthalene-fused N-acylbenzimidazole and is believed to proceed through intermediate formation of a phosphinyl radical cation. The resulting phosphonium salts are directly involved in the Wittig reaction leading to homologated alkenes.
Iron-Catalyzed Tunable and Site-Selective Olefin Transposition
Yu, Xiaolong,Zhao, Haonan,Li, Ping,Koh, Ming Joo
supporting information, p. 18223 - 18230 (2020/12/04)
The catalytic isomerization of C-C double bonds is an indispensable chemical transformation used to deliver higher-value analogues and has important utility in the chemical industry. Notwithstanding the advances reported in this field, there is compelling demand for a general catalytic solution that enables precise control of the C═C bond migration position, in both cyclic and acyclic systems, to furnish disubstituted and trisubstituted alkenes. Here, we show that catalytic amounts of an appropriate earth-abundant iron-based complex, a base and a boryl compound, promote efficient and controllable alkene transposition. Mechanistic investigations reveal that these processes likely involve in situ formation of an iron-hydride species which promotes olefin isomerization through sequential olefin insertion/β-hydride elimination. Through this strategy, regiodivergent access to different products from one substrate can be facilitated, isomeric olefin mixtures commonly found in petroleum-derived feedstock can be transformed to a single alkene product, and unsaturated moieties embedded within linear and heterocyclic biologically active entities can be obtained.
Cobalt-Catalyzed Migrational Isomerization of Styrenes
Zhao, Jiajin,Cheng, Biao,Chen, Chenhui,Lu, Zhan
supporting information, p. 837 - 841 (2020/01/31)
An efficient cobalt-catalyzed migrational isomerization of styrenes was developed using the thiazoline iminopyridine (TIP) ligand. This reaction is operationally simple and atom-economical using readily available starting materials to access trisubstituted alkenes. Even when using a 0.1 mol % catalyst loading, the reaction could be conducted in neat and completed in 1 h with excellent conversion and high E stereoselectivity.
Switch in Selectivity for Formal Hydroalkylation of 1,3-Dienes and Enynes with Simple Hydrazones
Li, Chao-Jun,Lv, Leiyang,Qiu, Zihang,Yu, Lin
supporting information, p. 6466 - 6472 (2020/03/13)
Controlling reaction selectivity is a permanent pursuit for chemists. Regioselective catalysis, which exploits and/or overcomes innate steric and electronic bias to deliver diverse regio-enriched products from the same starting materials, represents a powerful tool for divergent synthesis. Recently, the 1,2-Markovnikov hydroalkylation of 1,3-dienes with simple hydrazones was reported to generate branched allylic compounds when a nickel catalyst was used. As part of the effort, shown here is that a complete switch of Markovnikov to anti-Markovnikov addition is obtained by changing to a ruthenium catalyst, thus providing direct and efficient access to homoallylic products exclusively. Isotopic substitution experiments indicate that no reversible hydro-metallation across the metal-π-allyl system occurred under ruthenium catalysis. Moreover, this protocol is applicable to the regiospecific hydroalkylation of the distal C=C bond of 1,3-enynes.
Visible Light-Driven, Room Temperature Heck-Type Reaction of Alkyl Halides with Styrene Derivatives Catalyzed by B12 Complex
Chen, Li,Hisaeda, Yoshio,Shimakoshi, Hisashi
, p. 2877 - 2884 (2019/04/03)
A visible light driven Heck-type coupling reaction of alkyl halides with styrene and its derivatives catalyzed by the cobalamin derivative (B12) with the [Ru(bpy)3]Cl2 photosensitizer at room temperature is reported. The catalytic efficiencies of the B12 catalyst were compared to that of other cobalt complexes such as cobaloxime. Various control experiments supported a radical-based mechanism similar to those for typical B12 model reactions. A unique coupling reaction combined with 1,2-migration of the functional group is also reported. Mild reaction conditions using an environmentally benign cobalt catalyst derived from the natural B12 provided a practical protocol for the synthetic organic chemistry of the B12 catalyzed reaction system. (Figure presented.).
Method for synthesizing cis-olefin by catalyzing decarboxylation coupling reaction of NHP ester and aryl-terminated alkyne with iridium
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Paragraph 0085-0086; 0099; 0101, (2019/02/13)
The invention provides a method for synthesizing Z-selective olefin by catalyzing a decarboxylation coupling reaction of an NHP ester and aryl-terminated alkyne with iridium. The aryl-terminated alkyne and its derivative and the NHP ester undergo a one-po
Iron-Catalyzed Vinylic C?H Alkylation with Alkyl Peroxides
Ge, Liang,Jian, Wujun,Zhou, Huan,Chen, Shaowei,Ye, Changqing,Yu, Fei,Qian, Bo,Li, Yajun,Bao, Hongli
supporting information, p. 2522 - 2528 (2018/08/01)
A variety of alkyl peresters and alkyl diacyl peroxides, which are readily accessible from carboxylic acids, are utilized as general primary, secondary, and tertiary alkylating reagents for iron-catalyzed vinylic C?H alkylation of vinyl arenes, dienes, and 1,3-enynes. This transformation affords olefinic products in up to 98 % yield with high E/Z values. A broad range of functionalities, including carboxyl, boronic acid, methoxy, ester, amino, and halides, are tolerated. This protocol provides a facile approach to some olefins that are difficult to access, and hence, offers an alternative to existing systems. The synthetic utility of this method is demonstrated by late-stage functionalization of selected natural-product derivatives.
Irradiation-Induced Palladium-Catalyzed Decarboxylative Heck Reaction of Aliphatic N-(Acyloxy)phthalimides at Room Temperature
Wang, Guang-Zu,Shang, Rui,Fu, Yao
, p. 888 - 891 (2018/02/10)
It is reported that Pd(PPh3)2Cl2 in combination with 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (Xantphos) under irradiation of blue LEDs efficiently catalyzes a decarboxylative Heck reaction of vinyl arenes and vinyl heteroarenes with aliphatic N-(acyloxy)phthalimides at room temperature. A broad scope of secondary, tertiary, and quaternary carboxylates, including α-amino acid derived esters, can be applied as amenable substrates with high stereoselectivity. The experimental observation was explained by excitation-state reactivity of the palladium complex under irradiation to induce single-electron transfer to activate N-(acyloxy)phthalimides, and to suppress undesired β-hydride elimination of alkyl palladium intermediates.
Photoredox catalysis enabled alkylation of alkenyl carboxylic acids with: N -(acyloxy)phthalimide via dual decarboxylation
Xu, Kun,Tan, Zhoumei,Zhang, Haonan,Liu, Juanli,Zhang, Sheng,Wang, Zhiqiang
supporting information, p. 10719 - 10722 (2017/10/06)
A ruthenium based photoredox catalyst in combination with a substoichiometric amount of 1,4-diazabicyclo[2.2.2]octane (DABCO) efficiently catalyzed dual decarboxylative couplings between alkenyl carboxylic acids and N-(acyloxy)phthalimides derived from aliphatic carboxylic acids, delivering alkylated styrene derivatives in a high regio- and stereo-selective manner under mild reaction conditions. Various types of secondary, tertiary, and quaternary aliphatic carboxylic acids as well as α-amino acids can be used as suitable substrates. Mechanistic analysis suggested that the reaction proceeds through a radical mechanism mediated by a Ru(i)/Ru(ii) catalytic cycle with DABCO acting both as the base and the co-catalyst for single electron transfer.
