827-53-2Relevant academic research and scientific papers
Nickel complex catalyzed efficient activation of sp3and sp 2c-h bonds for alkylation and arylation of oxygen containing heterocyclic molecules
Gartia, Yashraj,Ramidi, Punnamchandar,Jones, Darin E.,Pulla, Sharon,Ghosh, Anindya
, p. 507 - 515 (2014/06/24)
A nickel(II) complex (1) of N,N'-bis(2,6-diisopropylphenyl)-2,6- pyridinedicarboxamido (L) ligand was examined for catalytic coupling of Grignard reagents with the C-H bond of oxygen containing heterocyclic compounds such as tetrahydrofuran and furan. The nickel( II) complex showed excellent activity in catalyzing C-H activation and further coupling with various Grignard reagents. The effective activation of the C-H bond proceeded under ambient reaction conditions with a short reaction time (1-2 h). The catalyst (1) displays high turnover frequency of 4,130 h-1with catalyst loading as low as 0.01 mol%. This catalytic route could prove to be an efficient mode of activation of sp3and sp2C-H bonds in various heterocycles for the preparation of synthetically and pharmaceutically relevant molecules. Springer Science+Business Media New York 2013.
Activation of sp3 and sp2 C-H bonds of oxygen containing heterocyclic molecules for alkylation and arylation reactions catalyzed by an iron complex
Gartia, Yashraj,Ramidi, Punnamchandar,Cheerla, Sreevishnu,Felton, Charlette M.,Jones, Darin E.,Das, Bhaskar C.,Ghosh, Anindya
, p. 253 - 259 (2014/07/07)
Activation of both sp3 and sp2 CH bonds is reported using an efficient iron(III) complex (1) of a ligand (N2,N6-bis(2,6- diisopropylphenyl)pyridine-2,6-dicarboxamide: L). The iron(III) complex showed catalytic activity of CC coupling reaction of oxygen containing heterocycles, e.g. tetrahydrofuran (THF), with various alkyl, allyl and aryl Grignard reagents under ambient reaction conditions. Complex 1 demonstrated excellent activity and reactions were completed within 30 min to 1 h. A high turnover frequency (TOF) of 1700 h-1 using a low catalyst loading of 0.02 mol% was obtained for the reaction. Interestingly, the catalyst was selective in activation of the CH bond adjacent to the oxygen in various oxygen containing heterocyclic molecules to yield 2-substitituted products.
Direct functionalization of tetrahydrofuran and 1,4-dioxane: Nickel-catalyzed oxidative C(sp3)-H arylation
Liu, Dong,Liu, Chao,Li, Heng,Lei, Aiwen
supporting information, p. 4453 - 4456 (2013/05/21)
CHoose nickel: The nickel-catalyzed oxidative arylation of C(sp 3)-H bonds has been achieved. Several substituted arylboronic acids and various C(sp3)-H bonds were found to be suitable substrates for this novel transformation, which is likely to proceed through a radical pathway. This method allows the introduction of simple ether derivatives to construct α-arylated ethers. FG=functional group. Copyright
New-quanidino-thiazol compounds, their preparation, and use as intermediates of famotidine process
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, (2008/06/13)
New 2-guanidino-thiazol compounds with the general formulas where R° represents an hydrogen atom or an alkyl group of low molecular weight, m = 2 to 7, n = 2 to 4, and being R an alkyl group of low molecular weight and that may contain from one N-alkylsilyl group, that are important intermediates for the famotidine preparation, medically used as inhibitor of the gastric secretion.
MODIFICATION OF SINGLET CARBENE REACTIVITIES BY SOLVENT
Tomoika, H.,Ozaki, Y.,Izawa, Y
, p. 4987 - 4994 (2007/10/02)
The solvent effect on the reactivity of singlet carbenes has been investigated.Competition reactions between pairs of alcohols for arylcarbenes in various solvents indicates that the O-H insertion selectivity is influenced only by 1,4-dioxane.Thus, phenylcarbene is some 33 times more reactive toward methanol relative to t-butyl alcohol in 90 molpercent dioxane than without solvent.Similar competition reactions between alcohol and olefin indicate that the O-H insertion-addition selectivities of arylcarbenes are considerably altered by dioxane.These results are interpreted as indicating that dioxane stabilizes singlet carbenes by complexing with its ione pairs of electrons.
The Photo-cycloaddition of Enol Ethers to Benzene
Gilbert, Andrew,Taylor, Grahame N.,Samsudin, Mohd. Wahid bin
, p. 869 - 876 (2007/10/02)
The photo-reactions of benzene with ethyl vinyl ether, n-butyl vinyl ether, 1,1-dimethoxyethylene, 2,3-dihydropyran, 2,3-dihydrofuran, 2,3-dihydro-1,4-dioxin, and 1,3-dioxole are described.The meta-photo-cycloaddition of ethyl vinyl ether and n-butyl vinyl ether to benzene shows little selectivity, and regio- and stereo-isomers are isolated. ortho-Cycloaddition is observed from all systems but only with 2,3-dihydrofuran as addend are both stereoisomers of the adduct formed, and although the exo-isomer is very photolabile, the endo-product is essentially stable under its conditions of formation.The ortho-cycloaddition of 1,1-dimethoxyethylene to benzene provides the first step in a convenient synthesis of cyclo-octatrienone.Contrary to previous proposals there is little correlation between the stereochemistry of the ortho-cycloaddition and preferred orientation of the addends in the ground state.The relationship between the relative efficiency of the two addition modes and ionisation potential of the ethylene is discussed.
