35234-87-8Relevant academic research and scientific papers
β,β'-Functionalized N,N-divinyl-N-trimethylsilyloxyamines via silylation of β-substituted aliphatic nitro compounds. The investigation of the mechanism of the process using selective trapping reagents
Ioffe, Sema L.,Lyapkalo, II'ya M.,Tishkov, Alexander A.,Danilenko, Vitaliy M.,Strelenko, Yuri A.,Tartakovsky, Vladimir A.
, p. 13085 - 13098 (1997)
Hitherto unknown N,N-divinyl-N-trimethylsilyloxyamines of the general formula |XC(R)=CH|2NOSiMe3 (X = CO2Me, CN, 5-methyloxycarbonylisoxazolin-3-yl; R = H, Me, CH(Me)CO2Me) were obtained with moderate to good yields by silylation of nitro compounds XCH(R)CH2NO2 with N,O-bis(trimethylsilyl)acetamide. The mechanism of this reaction was studied by the example of silylation of methyl-3-nitropropionate using selective trapping reagents. Trimethylsilyl ester of the starting aci-nitro compound and methyl 2-nitroso acrylate were intercepted as consecutive intermediates. Thus, the silylation of β-functionalized nitro compounds could be presented as a convenient route to practically unknown β-substituted nitroso-alkenes XC(R)=CHNO which behave as active 1,3-heterodienes towards ethyl vinyl ether used as trapping reagent.
Cycloadditions of two thiocarbonyl ylides with α,β-unsaturated esters and nitriles: Steric course and mechanism
Huisgen, Rolf,Mloston, Grzegorz,Giera, Henry,Langhals, Elke
, p. 507 - 519 (2002)
In the probably concerted cycloadditions of the sterically hindered thiocarbonyl ylide 1 with fumaronitrile, maleonitrile, and dimethyl fumarate, the dipolarophile configuration is retained whereas retention/inversion 99:1 for dimethyl maleate (51 times less reactive than fumarate) signals a small involvement of a two-step pathway. The latter becomes dominant when two acceptor groups stabilize the anionic terminus of a zwitterionic intermediate. Nonstereospecific cycloadditions of 1 with dimethyl 2,3-dicyanofumarate (16, retention/inversion 60:40) and dimethyl 2,3-dicyanomaleate (17, 76:24) were observed. Special conditions were required to avoid a preceding cis, trans isomerization, 16?17, catalyzed by thiadiazoline 4, the precursor of 1. In the case of the related thiocarbonyl ylide 37, this catalysis could not be suppressed and the same ratio of adducts (55:45) was obtained with 16 and 17.
1,3-CYCLOADDITIONS OF ALIPHATIC THIONE S-METHYLIDES TO DIMETHYL 2,3-DICYANOFUMARATE AND 2,3-DICYANOMALEATE; A TEST CASE FOR STERIC COURSE AND MECHANISM
Mloston, Grzegorz,Langhals, Elke,Huisgen, Rolf
, p. 5373 - 5376 (1989)
The 1,3-cycloadditions of thione S-methylides 2 and 9 to dimethyl 2,3-dicyanofumarate and 2,3-dicyanomaleate are nonstereospecific.A preceding cis,trans isomerization of the unsaturated dipolarophiles catalyzed by the thiadiazolines (precursors of the thione S-methylides) had to be suppressed in order to clarify the stereochemical leakage during the cycloaddition.
An unexpected reaction of diethyl phosphite with electron-deficient dialkyl dicyanofumarates
Mlostoń, Grzegorz,Celeda, Ma?gorzata,Heimgartner, Heinz
, p. 207 - 210 (2016)
Diethyl phosphite reacts with both dimethyl dicyanofumarate and dicyanomaleate in boiling 1,2-dichloroethane to yield, after chromatographic workup, a 1:1-mixture of the corresponding meso- and dl-dicyanosuccinates. The analogous transformation was observed in the cases of diethyl and diisopropyl dicyanofumarates. A reaction pathway via initial formation of a P-C bond followed by its hydrolytic cleavage is proposed.
Room temperature dynamic polymers based on Diels-Alder chemistry
Reutenauer,Buhler,Boul,Candau,Lehn
experimental part, p. 1893 - 1900 (2009/09/28)
Dynamers based on reversible Diels-Alder chemistry have been obtained and shown to undergo dynamic exchange at room temperature. Their study in solution by small-angle neutron scattering indicated the formation of long and highly flexible chains. Polydispersed molecules gave Tg values below room temperature, permitting the generation of a dynamic elastomer upon introduction of a dynamic cross-linking agent. The use of a system with a low equilibrium constant gives access to materials with interesting self-healing properties.
Reversible Diels-Alder reactions for the generation of dynamic combinatorial libraries
Boul, Peter J.,Reutenauer, Philippe,Lehn, Jean-Marie
, p. 15 - 18 (2007/10/03)
(Chemical Equation Presented) Condensation reactions between various dienes and dienophiles have been screened for reversibility. Functionalized fulvenes, bearing in particular biological groups, and cyanolefins have been found to react rapidly and reversibly, in the temperature range from -10 to +50°C. These results pave the way for the development of dynamic combinatorial libraries based on reversible Diels-Alder chemistry.
Chemical and Electrochemical Oxidative Dimerization of Carbonyl Compounds by Cerium(IV) Salts. A Comparative Study
Cho, Liu Yao,Romero, Jose Ricardo
, p. 8757 - 8760 (2007/10/02)
β-dicarbonyl and β-cyanocarbonyl compounds were dimerized chemically by CAN or by electrocatalysis using cerous nitrate as mediator.The saturated and unsaturated products of these oxidations are presented.
A Convenient Synthesis of Dialkyl (E)-2,3-Dicyanobutendioates
Yamada, Yoichi,Yasuda, Heinosuke
, p. 768 - 770 (2007/10/02)
Dialkyl (E)-2,3-dicyanobutendioates 4, potentially useful intermediates for the synthesis of a wide variety of heterocyclic compounds, are conveniently prepared by the reaction of alkyl bromocyanoacetates 2 with potassium thiocyanate in acetonitrile followed by treatment with water.The starting alkyl bromocyanoacetates are prepared by the photochemical reaction of the appropriate alkyl cyanoacetate with bromine in carbon tetrachloride.
