3854-80-6Relevant academic research and scientific papers
Organocatalytic Regiodivergent C?C Bond Cleavage of Cyclopropenones: A Highly Efficient Cascade Approach to Enantiopure Heterocyclic Frameworks
Cao, Jian,Fang, Ran,Liu, Jin-Yu,Lu, Hong,Luo, Yong-Chun,Xu, Peng-Fei
, p. 18863 - 18867 (2018)
Here a highly efficient cascade approach is reported that combines a cycloaddition reaction with a regioselective strain-release process to afford diverse heterocyclic frameworks through bifunctional catalysis. The cooperation of hydrogen-bonding network activation and a regiodivergent strain-assisted effect is the key to promoting this complex chemical transformation, leading to the generation of two different ring systems in high yields with excellent stereoselectivities. The reaction proceeded by a mechanism involving a “spring-loaded” intermediate with switchable C?C bond cleavages achieved by controllable ring-strain release. This reaction was also amenable to gram scale synthesis with only 0.1 mol % catalyst loading.
Fully Substituted Conjugate Benzofuran Core: Multiyne Cascade Coupling and Oxidation of Cyclopropenone
Yao, Liangliang,Hu, Qiong,Bao, Li,Zhu, Wenjing,Hu, Yimin
, p. 4971 - 4975 (2021/06/30)
An unprecedented C═C double bond cleavage of cyclopropenone and dioxygen activation by multiyne cascade coupling has been developed. This chemistry provides a novel, simple, and efficient approach to synthesize fully substituted conjugate benzofuran derivatives from simple substrates under mild conditions. The density functional theory (DFT) calculations reveal that the unique homolytic cleavages of cyclopropenone and molecular oxygen are crucial to the success of this reaction.
Lanthanide Silylamide-Catalyzed Synthesis of Pyrano[2,3- b]indol-2-ones
Chen, Qifa,Teng, Yue,Xu, Fan
, p. 4785 - 4790 (2021/06/28)
A lanthanide silylamide-catalyzed tandem reaction of isatins, diethyl phosphite, and 2,3-diarylcyclopropenones has been developed. A series of pyrano[2,3-b]indol-2-ones were synthesized in high yields. The cooperation of the Lewis acidity of the lanthanide center and the Bronsted basicity of the N(SiMe3)2 anion may be the key factor affecting the catalytic activity of lanthanide amides.
Cascade Ring-Opening Dual Halogenation of Cyclopropenones with Saturated Oxygen Heterocycles
Gao, Wen-Xia,Huang, Xiao-Bo,Liu, Miao-Chang,Miao, Wei-Hang,Wu, Hua-Yue,Zhou, Yun-Bing
supporting information, p. 9425 - 9430 (2021/12/14)
Represented is a CuX2- or I2-promoted ring-opening dual halogenation of cyclopropenones with saturated oxygen heterocycles, providing an efficient method for the synthesis of 3-haloacrylates. The ring-opening reaction enables the construction of two C–X (X = Cl, Br, or I) bonds and a C–O bond as well as the cleavage of two C–O bonds and a C–C bond in a single step. This protocol is highly atom economical, has an excellent substrate scope, and exhibits the ability for gram-scale reaction.
Iron-Catalyzed One-Step Synthesis of Isothiazolone/1,2-Selenazolone Derivatives via [3+1+1] Annulation of Cyclopropenones, Anilines, and Elemental Chalcogens
Wang, Hongchen,Yan, Rulong
, (2021/12/22)
Described herein is the one-step synthesis of isothiazolone/1,2-selenazolone derivatives via [3+1+1] cycloaddition of cyclopropenone derivatives, anilines, and elemental chalcogens. The cascade reaction involves the C?S, C?N, and N?S bond formation along with the cleavage of C?C bond. Both anilines and cyclopropenones are tolerated and give the corresponding products in 28–73% yields. (Figure presented.).
Organocatalyzed [3 + 2] Annulation of Cyclopropenones and β-Ketoesters: An Approach to Substituted Butenolides with a Quaternary Center
Li, Xuanyi,Han, Chunhua,Yao, Hequan,Lin, Aijun
, p. 778 - 781 (2017/03/01)
An unprecedented organocatalyzed [3 + 2] annulation of cyclopropenones and β-ketoesters has been developed. This reaction provides a direct approach to highly substituted butenolides with a quaternary center in moderate to good yields. The preliminary mechanism study verified that the enol intermediate is crucial to the reaction outcome and the intermolecular esterification and intramolecular Michael addition process were involved.
Cyclopropenylidene carbene ligands in palladium catalysed coupling reactions: Carbene ligand rotation and application to the Stille reaction
Chotima, Ratanon,Dale, Tim,Green, Michael,Hey, Thomas W.,McMullin, Claire L.,Nunns, Adam,Guy Orpen,Shishkov, Igor V.,Wass, Duncan F.,Wingad, Richard L.
experimental part, p. 5316 - 5323 (2011/06/27)
Reaction of [Pd(PPh3)4] with 1,1-dichloro-2,3- diarylcyclopropenes gives complexes of the type cis-[PdCl2(PPh 3)(C3(Ar)2)] (Ar = Ph 5, Mes 6). Reaction of [Pd(dba)2] with 1,1-dichloro-2,3-diarylcyclopropenes in benzene gave the corresponding binuclear palladium complexes trans-[PdCl2(C 3(Ar)2)]2 (Ar = Ph 7, p-(OMe)C 6H48, p-(F)C6H49). Alternatively, when the reactions were performed in acetonitrile, the complexes trans-[PdCl2(NCMe)(C3(Ar)2)] (Ar = Ph 10, p-(OMe)C6H411 and p-(F)C6H4) 12) were isolated. Addition of phosphine ligands to the binuclear palladium complex 7 or acetonitrile adducts 11 and 12 gave complexes of the type cis-[PdCl 2(PR3)(C3(Ar)2)] (Ar = Ph, R = Cy 13, Ar = p-(OMe)C6H4, R = Ph 14, Ar = p-(F)C 6H4, R = Ph 15). Crystal structures of complexes 6·3.25CHCl3, 10, 11·H2O and 12-15 are reported. DFT calculations of complexes 10-12 indicate the barrier to rotation about the carbene-palladium bond is very low, suggesting limited double bond character in these species. Complexes 5-9 were tested for catalytic activity in C-C coupling (Mizoroki-Heck, Suzuki-Miyaura and, for the first time, Stille reactions) and C-N coupling (Buchwald-Hartwig amination) showing excellent conversion with moderate to high selectivity.
Development of a catalytic platform for nucleophilic substitution: Cyclopropenone-catalyzed chlorodehydration of alcohols
Vanos, Christine M.,Lambert, Tristan H.
supporting information; experimental part, p. 12222 - 12226 (2012/02/02)
Cyclopropenone makes the switch: 2,3-Bis-(p-methoxyphenyl)cyclopropenone is a highly efficient catalyst for the chlorodehydration of 20 diverse alcohol substrates (see scheme; X=Cl). With oxalyl chloride as catalytic activator, this nucleophilic substitution proceeded through cyclopropenium-activated intermediates and resulted in complete stereochemical inversion in substrates with chiral centers.
Synthesis of 2-methyl-4, 6-diaryl-1, 2, 3-triazinones via diarylcyclopropenones
Matsumoto, Kiyoshi,Okada, Akihiro,Girek, Tomasz,Ikemi, Yukio,Kim, Jong Chul,Hayashi, Naoto,Yoshida, Hiroshi,Kakehi, Akikazu
, p. 325 - 328 (2007/10/03)
2-Methyl-4,6-bis(4-substituted-phenyl)-1,2,3-triazin-5(2H)-ones 9a-d were prepared from the coressponding cyclopropenones 4a-d in a similar fashion as described by us previously. One of the the structure of 9b was established by an X-ray analysis.
