70090-76-5Relevant academic research and scientific papers
Copper(ii)-catalyzed protoboration of allenes in aqueous media and open air
Nekvinda, Jan,Santos, Webster L.,Snead, Russell F.
supporting information, p. 14925 - 14931 (2021/09/04)
A method has been developed for the facile Cu(ii)-catalyzed protoboration of monosubstituted allenes in aqueous media under atmospheric conditions. The reaction occurs site selectively, favoring internal alkene protoboration to afford 1,1-disubstituted vinylboronic acid derivatives (up to 93?:?7) with modest to good yields. The method has been applied to a variety of phenylallene derivatives as well as alkyl-substituted allenes. This journal is
Trifluoromethylation of Allenes: An Expedient Access to α-Trifluoromethylated Enones at Room Temperature
Brochetta, Massimo,Borsari, Tania,Gandini, Andrea,Porey, Sandip,Deb, Arghya,Casali, Emanuele,Chakraborty, Arka,Zanoni, Giuseppe,Maiti, Debabrata
supporting information, p. 750 - 753 (2019/01/04)
A silver(I) catalyzed regioselective trifluoromethylation of allenes using Langlois's salt (NaOSOCF3) is demonstrated. This transformation enables direct expedient access to α-trifluoromethylated acroleins, which are valuable synthons for a number of pharmaceuticals and agrochemicals containing vinyl-CF3 moieties. Versatility of this trifluoromethylation method has been established with good yield and excellent regioselectivity. Preliminary experiments and computational studies were carried out to elucidate the mechanistic insight of this protocol.
Copper-Catalyzed Difunctionalization of Allenes with Sulfonyl Iodides Leading to (E)-α-Iodomethyl Vinylsulfones
Lu, Ning,Zhang, Zhiguo,Ma, Nana,Wu, Conghui,Zhang, Guisheng,Liu, Qingfeng,Liu, Tongxin
supporting information, p. 4318 - 4322 (2018/07/29)
A highly regioselective iodosulfonylation of allenes in the presence of CuI and 1,10-phenanthroline has been developed for the synthesis of various useful (E)-α-iodomethyl vinylsulfones in moderate to excellent yields. This practical reaction is fast, operationally simple, and in particular, proceeds under very mild conditions to afford the target products with high regio- and stereoselectivity. The selectivity was illustrated by a conceptual DFT analysis.
Palladium-catalyzed insertion of an allene into an aminal: Aminomethylamination of allenes by C-N bond activation
Hu, Jianhua,Xie, Yinjun,Huang, Hanmin
supporting information, p. 7272 - 7276 (2014/07/21)
A new and atom-economic palladium-catalyzed aminomethylamination of allenes with aminals by C-N bond activation is described. This direct and operationally simple method provides a fundamentally novel approach for the synthesis of 1,3-diamines. Mechanistic studies suggest that a unique cationic π-allylpalladium complex containing an aminomethyl moiety is generated as a key intermediate through the carbopalladation of the allene with a cyclometalated palladium-alkyl species.
Regioselective silylzincation of phenylallene derivatives
Yonehara, Mitsuhiro,Nakamura, Shinji,Muranaka, Atsuya,Uchiyama, Masanobu
supporting information; experimental part, p. 452 - 455 (2010/09/08)
This paper deals with our new approach for regio-controlled synthesis of exo/endo-vinylsilanes through silylzincation as a key reaction, using newly developed silylzinc reagents. In this system, by choosing appropriate zinc reagents, either exo-vinylsilane or endo-vinylsilane can be synthesized with good regioselectivity, using the same phenylallene substrates. (Chemical equation presented).
Acid-catalyzed conversion of 7-ethynyl- and 7-vinyleyclohepta-1,3, 5-trienes to substituted benzene derivatives
Minegishi, Shinya,Kamada, Jun,Takeuchi, Ken'ichi,Komatsu, Koichi,Kitagawa, Toshikazu
, p. 3497 - 3504 (2007/10/03)
The acid-catalyzed rearrangement in THF/TFA (5:1, v/v) of cyclohepta-1,3,5-trienes containing an α,β-unsaturated substituent at C-7 was investigated. 7-Ethynylcyclohepta-1,3,5-triene (1a) and its 1,4-di-tert-butyl (1b), 1,5-di-tert-butyl (1c), and 2,5-di-tert-butyl (1d) derivatives underwent isomerization to phenylallenes 2, 3, 7, and 3, respectively. 2,5-Di-tert-butyl-7-vinylcyclohepta-1,3,5-triene (17) gave a mixture (66:34) of (E)- and (Z)-1,4-di-tert-butyl-2-(1-propenyl)benzene (20). A mechanism involving the protonation of the norcaradiene tautomer (NCD), which is in equilibrium with cycloheptatriene (CHT) 1 or 17, followed by the cleavage of a three-membered ring to give an arenium ion, is proposed. In contrast, 2,5-di-tert-butyl-7-cyanocyclohepta-1,3,5-triene (12) and bis(cyclohepta-2,4,6-trien-1-yl)ethyne (21) did not give the expected products, probably due to the unfavorable energetics of the ring-opening step. A thermal 1,5-hydrogen shift predominates in these cases. Kinetic studies indicated that the rearrangement of 1a is significantly accelerated by the presence of tert-butyl groups on the seven-membered ring. The order of reactivity, 1a 〈 1b 〈 1c 〈 1d, is in agreement with the population of NCD forms at equilibrium, as estimated by the calculated CHT-NCD energy-difference and the 13C NMR chemical shifts of 1a-d, indicating the importance of the equilibrium concentration of the norcaradiene form as a rate-controlling factor. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
