396717-20-7Relevant academic research and scientific papers
Weak coordinated nitrogen functionality enabled regioselective C-H alkynylationviaPd(ii)/mono-N-protected amino acid catalysis
Liu, Bifu,Ouyang, Wensen,Nie, Jianhong,Gao, Yang,Feng, Kejun,Huo, Yanping,Chen, Qian,Li, Xianwei
, p. 11255 - 11258 (2020/10/06)
The exploration of weak coordinated amine derivative enabled regioselective C-H functionalization remains challenging due to the elusive achievement of reactivity and selectivity simultaneously. Herein, regioselective C-H alkynylation of various readily transformable nitrogen functionalities was developed with great efficiency, with the assistance of the mono-N-protected amino acid (MPAA) ligandviaPd(ii) catalysis proceedingvia5, 6 and 7-membered palladacycle intermediates.
Nickel-catalyzed direct alkynylation of C(sp2)-H bonds of amides: An "inverse Sonogashira strategy" to ortho-alkynylbenzoic acids
Landge, Vinod G.,Shewale, Chinmay H.,Jaiswal, Garima,Sahoo, Manoj K.,Midya, Siba P.,Balaraman, Ekambaram
, p. 1946 - 1951 (2016/04/05)
Nickel-catalyzed direct alkynylation of C(sp2)-H bonds of amides using commercially available, inexpensive 8-aminoquinoline as a removable bidentate directing group is described. The present ortho-alkynylation has a broad substrate scope, funct
N-Iodosuccinimide-Promoted Rapid Access to Indeno[1,2-c]pyrroles via [3+2] Annulation of Enamine-alkynes
Santhi, Jampani,Baire, Beeraiah
supporting information, p. 3817 - 3823 (2016/12/16)
We have developed a metal-free, N-iodosuccinimide (NIS)-promoted, cascade strategy for the efficient synthesis of biologically important indeno[1,2-c]pyrroles via a [3+2] annulation process of enamine-alkynes. This methodology had shown a very broad scope
Fluoro-ene reaction versus [2+2] cycloaddition in the thermal C 2-C6 cyclization of enyne-allenes: An experimental and theoretical investigation
Cinar, M. Emin,Vavilala, Chandrasekhar,Jaquet, Ralph,Bats, Jan W.,Schmittel, Michael
, p. 5166 - 5177 (2014/10/15)
A series of fluoroalkyl-substituted enyne-allenes have been synthesized by a new route with the aim of elucidating the possibility of a fluoro-ene reaction via an intermediate fulvenyl diradical generated in the thermal C 2-C6 (Schmittel) cyclization reaction. As a result of the strong C-F bond, fluorine atom transfer was not observed. Instead, 1H-cyclobuta[a]indenes were formed in good yields despite the high strain energy. DFT calculations at the B3LYP level of theory indicated that although the fluoro-ene reaction is the most exothermic reaction available, cyclobutene formation is kinetically favored over the [1,5]-fluorine shift by 5-15 kcal mol-1 in various model compounds. Copyright
Photochemical C2-C6 cyclization of enyne-allenes: Detection of a fulvene triplet diradical in the laser flash photolysis
Bucher, Goetz,Mahajan, Atul A.,Schmittel, Michael
supporting information; experimental part, p. 8815 - 8828 (2009/04/11)
(Chemical Equation Presented) A series of enyne-allenes, with and without benzannulation at the ene moiety and equipped with aromatic and carbonyl groups as internal triplet sensitizer units at the allene terminus, was synthesized. Both sets, the cyclohexenyne-allenes and benzenyne-allenes, underwent thermal C2-C6 cyclization exclusively to formal ene products. In contrast, the photochemical C2-C6 cyclization of enyne-allenes provided formal Diels-Alder and/or ene products, with higher yields for the benzannulated systems. A raise of the temperature in the photochemical cyclization of enyne-allene 1b′ led to increasing amounts of the ene product in relation to that of the formal Diels-Alder product. Laser flash photolysis at 266 and 355 nm as well as triplet quenching studies for 1b,b′ indicated that the C2-C6 cyclization proceeds via the triplet manifold. On the basis of a density functional theory (DFT) study, a short-lived transient (r = 30 ns) was assigned as a triplet allene, while a long-lived transient (τ = 33 μs) insensitive to oxygen was assigned as fulvene triplet diradical. An elucidation of the reaction mechanism using extensive DFT computations allowed rationalization of the experimental product ratio and its temperature dependence.
