201164-24-1Relevant academic research and scientific papers
Organocatalytic Enantioselective Selenosulfonylation of a C-C Double Bond to Form Two Stereogenic Centers in an Aqueous Medium
Chen, Zhili,Hu, Fangli,Huang, Shengli,Zhao, Zhengxing,Mao, Hui,Qin, Wenling
, p. 8100 - 8111 (2019/06/17)
Organocatalytic selenosulfonylation of the C-C double bond of α,β-unsaturated ketones to construct two contiguous stereogenic centers in an aqueous medium was described. A series of α-selenyl and β-sulfonyl ketones with various functional groups were synthesized in good yields and enantioselectivities with saturated NaCl solution as the solvent. In addition, this protocol had been successfully scaled up to a decagram scale via a simple workup procedure.
Decarboxylative allylation of glyoxylic acids with diallyl carbonate
Manjolinho, Filipe,Gruenberg, Matthias F.,Rodriguez, Nuria,Goossen, Lukas J.
supporting information; experimental part, p. 4680 - 4683 (2012/10/08)
A catalyst system consisting of Pd(PPh3)4 and P(pTol)3 was found to effectively promote the intermolecular decarboxylative coupling of α-oxocarboxylic acids with diallyl carbonate to give α,β-unsaturated ketones. The key advantage of the new reaction protocol is that preformation of the allyl esters is not required. The reaction is believed to proceed via phosphane-mediated decarboxylation of the α-oxocarboxylates, leading to acyl anion equivalents that are allylated within the coordination sphere of the palladium catalyst. Under the reaction conditions, the double bond then migrates into conjugation with the carbonyl group. Copyright
Synthesis of α,β-unsaturated ketones by Pd-catalyzed decarboxylative allylation of α-oxocarboxylates
Rodriguez, Nuria,Manjolinho, Filipe,Gruenberg, Matthias F.,Goossen, Lukas J.
, p. 13688 - 13691 (2012/01/15)
A palladium/p-tolylphosphine system has been developed that catalyzes the extrusion of carbon dioxide from α-oxocarboxylic acid allyl esters, leading to α,β-unsaturated ketones (see scheme). The palladium complex activates the substrate and mediates the carbon-carbon bond formation to give allyl ketones, and subsequent double bond shift to the α,β position. The actual decarboxylation step with formation of the acyl nucleophile is promoted by phosphine.
Asymmetric hydrocyanation of α,β-unsaturated ketones into β-cyano ketones with the [Ru(phgly)2(binap)]/C6H 5OLi catalyst system
Kurono, Nobuhito,Nii, Noriyuki,Sakaguchi, Yusuke,Uemura, Masato,Ohkuma, Takeshi
supporting information; experimental part, p. 5541 - 5544 (2011/07/08)
Enantioselective conjugate addition of HCN to α,β-unsaturated ketones catalyzed by the combined system of [Ru{(S)-phgly}2{(S)- binap}] and C6H5OLi has afforded β-cyano ketones in high yield (see scheme). No detectable amount of the corresponding 1,2-adduct was produced and tert-C4H9OCH3 was the solvent of choice. The cyanation was conducted with a substrate-to-catalyst molar ratio in the range of 200:1-1000:1 at -20-0°C. Copyright
Difluoro-λ3-bromane-induced oxidative carbon-carbon bond-forming reactions: Ethanol as an electrophilic partner and alkynes as nucleophiles
Ochiai, Masahito,Yoshimura, Akira,Mori, Takeshi,Nishi, Yoshio,Hirobe, Masaya
, p. 3742 - 3743 (2008/09/21)
Reported here for the first time are the oxidative couplings of alkynes and primary alcohols yielding conjugated enones. Although the BF3-catalyzed reaction of terminal alkynes with p-trifluoromethylphenyl(difluoro)-λ3-bromane results in the fluoro-λ3-bromanation of triple bonds to afford (E)-β-fluorovinyl-λ3-bromanes, reaction of an alkyne with the difluoro-λ3-bromane in the presence of an alcohol and BF3-Et2O affords directly conjugated enones in good yields. The reaction proceeds in a highly stereo- and regioselective manner under metal-free conditions. Interestingly, no formation of enones was detected, when difluoro-λ3-iodane p-CF3C6H4IF2 was used instead of the λ3-bromane. A mechanism involving a λ3-bromane-induced oxidation of an alcohol to an aldehyde, [2 + 2] cyclization with alkynes yielding 2H-oxetes, and finally the electrocyclic ring opening is discussed. Copyright
PYRIDINE AND PYRIMIDINE DERIVATIVES AS MGIUR2 ANTAGONISTS
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Page/Page column 33, (2010/11/29)
The present invention relates to compounds of formula (I), a process for the manufacture thereof, pharmaceutical compositions containing them, and their use for treating CNS disorders:wherein A, B, X, Y, R1, R2, R3 and R4 are as defined in the description and claims.
A Substituted Hypersensitive Radical Probe for Enzyme-Catalyzed Hydroxylations: Synthesis of Racemic and Enantiomerically Enriched Forms and Application in a Cytochrome P450-Catalyzed Oxidation
Toy, Patrick H.,Dhanabalasingam, Bhavani,Newcomb, Martin,Hanna, Imad H.,Hollenberg, Paul F.
, p. 9114 - 9122 (2007/10/03)
The syntheses of racemic and enantiomerically enriched trans-1-methyl-2-(4-(trifluoromethyl)phenyl)cyclopropane (3) and the possible oxidation products from enzyme-catalyzed hydroxylation of 3 at the methyl group are reported. The important intermediate in the production of 3 was the Weinreb amide of the 2-arylcyclopropanecarboxylic acid which could be prepared in diastereomerically pure form and which also served as an intermediate for production of the cyclic oxidation products of 3. Hydroxylation of 3 by the cytochrome P450 isozyme CYP2B1 gave cyclic and ring-opened products. The product ratios support an insertion mechanism for the enzyme-catalyzed hydroxylation reaction in which minor amounts of rearranged products are produced by radical fragmentation within the transition structure of the insertion and by a competing reaction involving a cationic species. Formation of cationic rearrangement products by a heterolytic fragmentation reaction of a first-formed protonated alcohol product is suggested on the basis of the apparent amounts of cationic products formed in the hydroxylation of 3. This pathway for cation production appears to require that the activated enzyme complex (equivalent to enzyme-substrate-H2O2) oxidizes substrate before water dissociates to give an iron-oxo species.
