4888-39-5Relevant academic research and scientific papers
Nucleophilic Reactivities of Bis-Acceptor-Substituted Benzyl Anions
Puente, ángel,Ofial, Armin R.,Mayr, Herbert
supporting information, p. 1196 - 1202 (2017/03/11)
The kinetics of the reactions of bis-acceptor-substituted benzyl anions (PhCXY–, X,Y = CN, CO2Et, COPh, SO2Ph) with benzhydrylium ions and quinone methides (reference electrophiles) have been determined in dimethyl sulfoxide solution at 20 °C. The reactions follow second-order kinetics, first order with respect to the electrophile and first order with respect to the carbanion. The addition of 18-crown-6 ether, which efficiently coordinates to the anions' counter ions K+, did not affect the kinetics, which indicates that the measured rate constants refer to the reactivities of the nonpaired carbanions. Comparison with the reactivities of the structurally analogous secondary carbanions HCXY– shows that replacement of H at the carbanionic center by Ph reduces the nucleophilic reactivities towards a reference benzhydrylium ion by factors in the range of only 1.2 (X,Y = SO2Ph) to 6 (X,Y = CO2Et). The plots of lg k2 versus the electrophilicity parameters E of the reference electrophiles are linear, thereby indicating that the correlation lg k2(20 °C) = sN(E + N), which characterizes nucleophiles by the two solvent-dependent parameters sN and N and electrophiles by the parameter E, is applicable. In this way, it becomes possible to integrate these carbanions into our comprehensive nucleophilicity scale, which provides a direct comparison of the nucleophilic reactivities of different families of compounds.
Aryl(chloro)methyl 4-tolyl sulfoxides: Synthesis and application to the synthesis of α-aryl ketones
Fukuda, Shigehiko,Tsuji, Kazuhito,Musashi, Jun,Nonaka, Ryo,Kimura, Tsutomu,Satoh, Tsuyoshi
, p. 3615 - 3626 (2011/12/16)
Aryl(chloro)methyl 4-tolyl sulfoxides were synthesized from arylmethyl 4-tolyl sulfoxides in moderate-to-good yields by sequential treatment with lithium diisopropylamide and tosyl chloride at low temperatures. Treatment of the lithium α-sulfinyl carbanion of the aryl(chloro)methyl 4-tolyl sulfoxides with aldehydes or ketones resulted in the formation of adducts in good-to-high yields. Treatment of these adducts with tert-butylmagnesium chloride gave the corresponding magnesium alkoxides. On treatment with isopropylmagnesium chloride, the alkoxides gave the corresponding magnesium β-oxido carbenoids, which rearranged to give α-aryl ketones in good-to-high yields. The magnesium enolate intermediates generated by rearrangement of the -oxido carbenoids could also be trapped with electrophiles to give α-aryl α-substituted ketones. These procedures offer a good method for the synthesis of a variety of α-aryl ketones from aldehydes and ketones. Georg Thieme Verlag Stuttgart. New York.
Reactions of copper(II) β-diketonates under free radical conditions. II. Diazonium salts as aryl radicals source in the arylation of β-diketones
Lorris, Maria E.,Abramovitch, Rudolph A.,Marquet, Jorge,Moreno-Manas, Marcial
, p. 6909 - 6916 (2007/10/02)
Copper complexes of 2,2,6,6-tetramethylheptane-3,5-dione and other β-diketones afford α-aryl-β-diketones when treated with arenediazonium tetrafluoroborates and copper powder in dichloromethane.
Photochemical Reaction of Phenyliodonium Ylides of β-Dicarbonyl Compounds with Terminal Alkynes
Kalogiannis, Stavros,Spyroudis, Spyros
, p. 5041 - 5044 (2007/10/02)
The photochemical reaction of phenyliodonium ylides of acyclic β-dicarbonyl compounds bearing at least one benzoyl group with terminal alkynes leads to the formation of 4-substituted-2-acyl-1-naphthol derivatives, probably through iodanes and ethynylated
Reaction of Aryl Aldehydes with Thiocyanates in the Presence of Tributylphosphine
Yokoyama, Masataka,Ohteki, Hiroko,Kurauchi, Masahiko,Hoshi, Kazuko,Yanagisawa, Eizaburo,et al.
, p. 2635 - 2640 (2007/10/02)
Aryl aldehydes react with methyl thiocyanate in the presence of tributylphosphine to afford S-methyl thiobenzoates and arylacetonitriles in good yields.This is a novel disproportionation reaction involving carbon-carbon bond formation.These compounds thus obtained are easily converted into deoxybenzoins using sodium hydride.On the other hand, p-dialkylaminobenzaldehydes react with methyl thiocyanate under the same conditions to furnish both the corresponding trans-dicyanostilbenes and succinonitriles in moderate yields.Finally, the reaction was carried out with aryl thiocyanates resulting in the formation of addition products.
DEOXYBENZOINS FROM AROMATIC ALDEHYDES
Yokoyama, Masataka,Hoshi, Kazuko,Imamoto, Tsuneo
, p. 1615 - 1616 (2007/10/02)
Aromatic aldehydes were easily converted into the corresponding deoxybenzoins by treatment with methyl thiocyanate in the presence of tributylphosphine, followed by addition of sodium hydride.
