112970-69-1Relevant academic research and scientific papers
Synthesis of Functionalized Alkenes by a Transition-Metal-Free Zweifel Coupling
Armstrong, Roly J.,Niwetmarin, Worawat,Aggarwal, Varinder K.
, p. 2762 - 2765 (2017)
The Zweifel reaction is a powerful method for the synthesis of alkenes, serving as a transition-metal-free alternative to the Suzuki-Miyaura reaction. To date, the scope of the Zweifel coupling has been rather narrow and has focused mainly on the coupling of vinyllithium reagents to synthesize simple aryl- and alkyl-substituted olefins. Herein, the development of a general transition-metal-free coupling process enabling the coupling of Grignard reagents or organolithiums is described. This method enables the enantiospecific synthesis of a wide variety of functionalized acyclic and cyclic olefin products.
Copper-Catalyzed Transfer Hydrodeuteration of Aryl Alkenes with Quantitative Isotopomer Purity Analysis by Molecular Rotational Resonance Spectroscopy
Alansari, Isabella Y.,Clark, Joseph R.,Holdren, Martin S.,Neill, Justin L.,Pate, Brooks H.,Reyes, Albert,Sloane, Samantha E.,Sonstrom, Reilly E.,Vang, Zoua Pa
supporting information, p. 7707 - 7718 (2021/06/21)
A copper-catalyzed alkene transfer hydrodeuteration reaction that selectively incorporates one hydrogen and one deuterium atom across an aryl alkene is described. The transfer hydrodeuteration protocol is selective across a variety of internal and terminal alkenes and is also demonstrated on an alkene-containing complex natural product analog. Beyond using 1H, 2H, and 13C NMR analysis to measure reaction selectivity, six transfer hydrodeuteration products were analyzed by molecular rotational resonance (MRR) spectroscopy. The application of MRR spectroscopy to the analysis of isotopic impurities in deuteration chemistry is further explored through a measurement methodology that is compatible with high-throughput sample analysis. In the first step, the MRR spectroscopy signatures of all isotopic variants accessible in the reaction chemistry are analyzed using a broadband chirped-pulse Fourier transform microwave spectrometer. With the signatures in hand, measurement scripts are created to quantitatively analyze the sample composition using a commercial cavity enhanced MRR spectrometer. The sample consumption is below 10 mg with analysis times on the order of 10 min using this instrument - both representing order-of-magnitude reduction compared to broadband MRR spectroscopy. To date, these measurements represent the most precise spectroscopic determination of selectivity in a transfer hydrodeuteration reaction and confirm that product regioselectivity ratios of >140:1 are achievable under this mild protocol.
Direct α-Acylation of Alkenes via N-Heterocyclic Carbene, Sulfinate, and Photoredox Cooperative Triple Catalysis
Liu, Kun,Studer, Armido
supporting information, p. 4903 - 4909 (2021/05/04)
N-Heterocyclic carbene (NHC) catalysis has emerged as a versatile tool in modern synthetic chemistry. Further increasing the complexity, several processes have been introduced that proceed via dual catalysis, where the NHC organocatalyst operates in concert with a second catalytic moiety, significantly enlarging the reaction scope. In biological transformations, multiple catalysis is generally used to access complex natural products. Guided by that strategy, triple catalysis has been studied recently, where three different catalytic modes are merged in a single process. In this Communication, direct α-C-H acylation of various alkenes with aroyl fluorides using NHC, sulfinate, and photoredox cooperative triple catalysis is reported. The method allows the preparation of α-substituted vinyl ketones in moderate to high yields with excellent functional group tolerance. Mechanistic studies reveal that these cascades proceed through a sequential radical addition/coupling/elimination process. In contrast to known triple catalysis processes that operate via two sets of interwoven catalysis cycles, in the introduced process, all three cycles are interwoven.
Suzuki-Miyaura cross-coupling reactions of potassium vinyltrifluoroborate with aryl and heteroaryl electrophiles
Molander, Gary A.,Brown, Adam R.
, p. 9681 - 9686 (2007/10/03)
We have previously reported that the palladium-catalyzed cross-coupling reaction of potassium vinyltrifluoroborate with aryl electrophiles proceeds with good yields. Herein, we describe recent progress in optimizing the reaction, as well as outlining the scope and limitations of the reaction. The cross-coupling reaction can generally be effected using 2 mol % of PdCl2 and 6 mol % of PPh3 as a catalyst system in THF/H2O with Cs 2CO3 as a base. Moderate to good yields are obtained in the presence of a variety of functional groups.
Palladium-Catalyzed Coupling of 2-Bromoanilines with Vinylstannanes. A Regiocontrolled Synthesis of Substituted Indoles
Krolski, Michael E.,Renaldo, Alfred F.,Rudisill, Duane E.,Stille, J. K.
, p. 1170 - 1176 (2007/10/02)
The palladium-catalyzed cross-coupling reaction of aryl halides and triflates with vinylstannane reagents has been used to produce a variety of substituted indoles.The mild reaction conditions and selectivity inherent in the coupling reaction have been utilized to produce regiochemically pure 4-, 5-, and 6-substituted indoles.
