122948-45-2Relevant academic research and scientific papers
Design, synthesis, and structure of alkyl 1H-pyrazolecarboxylates from a raspberry ketone methyl ether
Campos, Patrick T.,Cargnelutti, Roberta,Flores, Alex F. C.,Goulart, Taís B.,Moura, Sidnei,Neves, Adriana M.,Soares, Mayara S. P.,Stefanello, Francieli M.
, p. 1314 - 1320 (2020)
[Figure not available: see fulltext.] This paper reports a one-pot synthesis of 5-[2-(4-methoxyphenyl)ethyl]-1H-pyrazole-3-carboxylates via cyclocondensation of 1,1,1-trichloro-4-methoxy-6-(4-methoxyphenyl)hex-3-en-2-one with hydrazine hydrochloride in RO
An acetal acylation methodology for producing diversity of trihalomethyl-1,3-dielectrophiles and 1,2-azole derivatives
Bare?o, Valéria D.O.,Santos, Daiane S.,Frigo, Leandro M.,de Mello, Debora L.,Malavolta, Juliana L.,Blanco, Rogerio F.,Pizzuti, Lucas,Flores, Darlene C.,Flores, Alex F.C.
, p. 244 - 264 (2020/01/03)
A series of functionalized 1,1,1-trihalo-4-methoxy-3-alken-2-ones [CX3C(O)CR1=CROMe, where X = F or Cl; R = n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-tridecyl, (CH2)2CH=C(Me)2, (CH2)2Ph, (CH2)2-(4-HOC6H4), (CH2)2-(4-MeOC6H4), (CH2)2CO2Me, (CH2)3CO2Me, CH(SMe)CH3, CH2(2-MeOC6H4), and R1 = H, and R = H and R1 = n-decyl] were synthesized from respective alkyl methyl ketones or aldehyde via acetal acylation using trifluoroacetic anhydride and trichloroacetyl chloride. 1,1,1-Trihalo-4-methoxy-3-alken-2-ones with acid-compatible substituents were easily hydrolyzed to respective trihalomethyl-1,3-diketones. The 1,1,1-trihalo-4-methoxy-3-alken-2-ones and/or respective trihalomethyl-1,3-diketones were reacted regiospecifically with hydroxylamine hydrochloride, leading to isoxazole derivatives, and with hydrazines, leading to respective 1H-pyrazole derivatives. The structures of all compounds were assigned based on nuclear magnetic resonance (NMR) and mass spectrometric data. This method represents an efficient pathway for the regioselective trihaloacetylation of asymmetrically substituted alkyl methyl ketones and highly self-condensing aldehydes. Moreover, this approach allows the introduction of biologically recognizable moieties, such as those from levulinic acid, sulcatone (prenyl), benzylacetone, anisylacetone, and raspberry ketone, as synthetic molecular targets.
An efficient protection of carbonyls and deprotection of acetals using decaborane
Lee, Seung Hwan,Lee, Ji Hee,Yoon, Cheol Min
, p. 2699 - 2703 (2015/10/07)
Carbonyls were efficiently converted to the corresponding dimethyl acetals at room temperature using trimethyl orthoformate and 1 mol% of decaborane under a nitrogen atmosphere. In turn, acetals were deprotected to the corresponding carbonyls using 1 mol% of decaborane in aqueous THF chemoselectively.
Lifetimes of Oxocarbenium Ions in Aqueous Solution from Common Ion Inhibition of the Solvolysis of α-Azido Ethers by Added Azide Ion
Amyes, Tina L.,Jencks, William P.
, p. 7888 - 7900 (2007/10/02)
Rate constants for hydration of the oxocarbenium ions derived from a series of carbonyl compounds have been determined from common ion inhibition of the solvolysis of the corresponding α-azido ethers by trapping of the oxocarbenium ion intermediate with added azide ion, assuming kaz = 5E9 M-1s-1: acetophenone, kHOH = 5E7; acetone, 1E9; 4-methoxybutanone, 2E9; methoxyacetone, 4E9; benzaldehyde, 2E9; propionaldehyde, 2E10 s-1.Substitution on the reacting carbon atom affects log kHOH 0.4 as much as log Keq.Resonance effects are much larger than polareffects of substituents on kHOH, compared with Keq; this represents imbalance in the expression of these effects in the transition state.Use of these substituent effects to estimate the lifetime of glycosyl and methoxymethyl oxocarbenium ions gives values of kHOH ca. 1E12 s-1 for the glycosyl cation and 1E12-1E15 s-1 for the methoxymethyl cation.It is concluded that the glycosyl cation has a short but significant lifetime in aqueous solution and that there is little or no barrier for hydration of the methoxymethyl cation.The effects of substituents on the rate constants for addition to oxocarbenium ions are smaller than those for addition to the corresponding carbonyl compounds.The decrease in reactivity toward water of protonated acetone compared with the corresponding oxocarbenium ion by ca. 1E5 suggests that the proton occupies an intermediate position between the carbonyl group and water.The dependence of log kROH on pKROH for the addition of alcohols to oxocarbenium ions derived from derivatives of butanone and propionaldehyde in aqueous alcohol mixtures follows slopes of 0.5 and 0.1, respectively.
