6443-92-1Relevant academic research and scientific papers
C-F activation reactions at germylium ions: Dehydrofluorination of fluoralkanes
Braun, Thomas,Mei?ner, Gisa,Rachor, Simon G.,Talavera, Maria
supporting information, p. 4452 - 4455 (2020/05/13)
Reactions of the trityl cations with germanes afford the germylium ions [R3Ge][B(C6F5)4] (1a: R = Et, 1b: R = Ph, 1c: R = nBu). These compounds react with germane or fluorogermane to give polynuclear species, which are sources of the mononuclear ions, The latter convert with phosphines to yield the [R3Ge-PR3]+ (4a: R = Et, 4b: R = Ph) cations. Catalytic dehydrofluorination reactions were observed for the C-F bond activation of fluoroalkanes when using germanes as hydrogen source.
CATALYSTS AND CATALYTIC PROCESSES
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Page/Page column 19, (2017/05/28)
A process for migrating C=C double bonds within an unsaturated organic compound is described. The process involves contacting an unsaturated organic compound starting material with a heteropoly acid catalyst in the presence of light having a wavelength of less than or equal to 700 nm. Also described is a process for the preparation of novel heteropoly acids having markedly increased surface area.
General catalyst control of the monoisomerization of 1-alkenes to trans -2-alkenes
Larsen, Casey R.,Erdogan, Gulin,Grotjahn, Douglas B.
supporting information, p. 1226 - 1229 (2014/02/14)
After searching for the proper catalyst, the dual challenges of controlling the position of the double bond, and cis/trans-selectivity in isomerization of terminal alkenes to their 2-isomers are finally met in a general sense by mixtures of (C5Me5)Ru complexes 1 and 3 featuring a bifunctional phosphine. Typically, catalyst loadings of 1 mol % of 1 and 3 can be employed for the production of (E)-2-alkenes at 40-70 C. Catalyst comprising 1 and 3 avoids more than any other known example the thermodynamic equilibration of alkene isomers, as the trans-2-alkenes of both nonfunctionalized and functionalized alkenes are generated.
Graphite oxide activated zeolite NaY: Applications in alcohol dehydration
Todd, Alexander D.,Bielawski, Christopher W.
, p. 135 - 139 (2013/03/29)
A mixture of graphite oxide (GO) and the zeolite NaY (Si/Al = 5.1) was used to dehydrate various alcohols to their respective olefinic products. Using conditions optimized for 4-heptanol (15 wt% GO-NaY (1 : 1 wt/wt), 150°C, 30 min), a series of secondary and tertiary aliphatic alcohols were cleanly dehydrated in moderate to excellent conversions (27.5-97.2%). Several primary alcohols were also dehydrated, although higher catalyst loadings (200 wt% GO-NaY (1 : 1) and longer reaction times (3 h) were required. The enhanced dehydration activity was attributed to the ability of GO to convert NaY to an acidic form and without the need for ammonium cation exchange and/or high temperature calcination. The Royal Society of Chemistry 2013.
METHOD OF RAPID METHYLATION, KIT FOR PREPARING PET TRACER AND METHOD OF PRODUCING PET TRACER
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Page/Page column 10, (2009/07/10)
It is intended to provide a method of rapid methylation of an aromatic compound or an alkenyl compound, which is capable of obtaining an aromatic compound or an alkenyl compound labeled with a methyl group or a fluoromethyl group under a mild condition rapidly in high yield using an organic boron compound whose toxicity is not so high as a substrate; a kit for preparing a PET tracer to be used in the same, and a method of producing a PET tracer using the same. In an aprotic polar solvent, methyl iodide or X-CH2F (wherein X is a functional group which can be easily released as an anion), an organic boron compound in which an aromatic ring or an alkenyl group is attached to boron are subjected to cross-coupling in the presence of a palladium(0) complex, a phosphine ligand, and a base.
Palladium(0)-mediated rapid methylation and fluoromethylation on carbon frameworks by reacting methyl and fluoromethyl iodide with aryl and alkenyl boronic acid esters: Useful for the synthesis of [11C]CH 3-C-and [18F]FCH2-C-containing PET tracers (PET = positron emission tomography)
Doi, Hisashi,Ban, Ikuya,Nonoyama, Akihito,Sumi, Kengo,Kuang, Chunxiang,Hosoya, Takamitsu,Tsukada, Hideo,Suzuki, Masaaki
experimental part, p. 4165 - 4171 (2009/12/01)
The rapid methylation and fluoromethylation on aryl and alkenyl carbon frameworks by reacting methyl and fluoromethyl iodide with aryl and alkenyl boronates have been studied with the focus on the realization of the synthesis of [11C]CH3- and [18F]FCH2-labeled positron emission tomography (PET) tracers. The coupling of methyl iodide and pinacol phenylboronate (40 equiv) is accomplished in > 91% yield within 5 min at 60 °C under the conditions of [Pd2(dba)3]/P(o- CH3C6H4)3/K2CO 3 (0.5:2:2; dba = di-benzylideneacetone) in DMF. The reaction shows a high generality and is applicable to various types of aryl and alkenyl boronates, giving the corresponding methylated derivatives in high yields (80-99). This reaction is also useful for the rapid incorporation of the fluoromethyl group. Thus, this boron protocol provides a firm chemical basis for the synthesis of 11C- and 18F-incorporated PET tracers and can be used as a complementary method for [11C]methylation together with our previous and ongoing processes using organotributylstannanes.
METHOD OF RAPID METHYLATION OF ALKENE COMPOUND AND KIT FOR PET TRACER PREPARATION USING THE SAME
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Page/Page column 7, (2008/12/07)
To provide a method of rapid methylation of alkenes, which is applicable to the preparation of a PET tracer and which enables alkenes to be methylated through cross coupling between SP2 (alkenyl) and SP3 (alkyl) carbon atoms rapidly and in a high yield. Methyl iodide and an alkenyltrialkylstannane are subjected to cross coupling in an aprotic polar solvent in the presence of a palladium complex having a valence of 0, a phosphine ligand, a cuprous halide, and a carbonate and/or alkali metal fluoride.
Synthesis of metal complexes of polyalkylene(arylene) phosphorous amides
Teleshev,Te, Van,Mishina,Abrashina,Nifant'ev
experimental part, p. 1334 - 1337 (2009/02/07)
Reactions of phosphorous triamides with symmetrical diols in equimolar ratio were studied. These reactions result in formation of unique poly(oligo)amidophosphorous systems. The products obtained are used as ligands for the synthesis of metal complexes of a new type.
Pt/[Fe]ZSM-5 modified by Na and Cs cations: An active and selective catalyst for dehydrogenation of n-alkanes to n-alkenes
Li, Xuebing,Iglesia, Enrique
, p. 594 - 596 (2008/09/21)
Pt clusters within [Fe]ZSM-5 channels provide active and stable sites for the selective catalytic dehydrogenation of n-alkanes to n-alkenes. Cs and Na cations titrate acid sites and inhibit skeletal isomerization and cracking side reactions. The Royal Soc
Rapid methylation on carbon frameworks useful for the synthesis of 11CH3-incorporated PET tracers: Pd(0)-mediated rapid coupling of methyl iodide with an alkenyltributylstannane leading to a 1-methylalkene
Hosoya, Takamitsu,Sumi, Kengo,Doi, Hisashi,Wakao, Masahiro,Suzuki, Masaaki
, p. 410 - 415 (2007/10/03)
The Pd(0)-mediated rapid coupling of methyl iodide with an excess of alkenyltributylstannane was examined with the aim of incorporating a short-lived 11C-labeled methyl group into a biologically significant organic compound with a 1-methylalkene unit for the synthesis of a PET tracer. Four sets of reaction conditions (A-D) were used, all performed in DMF at 60 °C for 5 min. Condition B, using CH3I/stannane/Pd2(dba) 3/P(o-tolyl)3/CuCl/K2CO3 (1: 40: 0.5: 4-6: 2: 5), works well in almost all cases. Condition D, using CH 3I/stannane/Pd2(dba)3/P(o-tolyl) 3/CuX (X = Br, Cl, or I)/CsF (1: 40: 0.5-5: 2-20: 2-20: 5-50), shows the best results with regard to general applicability to tin substrates, affording the corresponding methylated product in >90% yield based on consumption of methyl iodide. P(t-Bu)2Me was less effective than P(o-tolyl)3, particularly for α,β-unsaturated carbonyl substrates. No regio- or stereoisomerization occurred under these reaction conditions. The efficiency of the protocol was demonstrated by synthesis of an 11C-methylated compound. The Royal Society of Chemistry 2006.
