26127-08-2Relevant articles and documents
Biochemical Responses of Wheat Seedlings on the Introduction of Selected Chiral Ionic Liquids to the Soils
Pawlowska, Barbara,Feder-Kubis, Joanna,Telesiński, Arkadiusz,Biczak, Robert
, p. 3086 - 3095 (2019/03/19)
In this study, new chiral ionic liquids (CILs) were obtained from the natural-origin material (1R,2S,5R)-(-)-menthol. The physicochemical characteristics of the studied imidazolium salts were investigated. The obtained 3-ethyl-1-[(1R,2S,5R)-(-)-menthoxy-m
Chiral protic imidazolium salts with a (-)-menthol fragment in the cation: Synthesis, properties and use in the Diels-Alder reaction
Janus, Ewa,Gano, Marcin,Feder-Kubis, Joanna,So?nicki, Jacek
, p. 10318 - 10331 (2018/03/26)
New chiral protic imidazolium salts containing a (1R,2S,5R)-(-)-menthol substituent in the cation and four different anions (chloride, hexafluorophosphate, trifluoromethanesulfonate and bis(trifluoromethylsulfonyl)imide) were efficiently prepared and exte
Synthesis and spectroscopic properties of symmetrical ionic liquids based on (?)-menthol
Feder-Kubis, Joanna
, p. 63 - 70 (2017/01/14)
Several symmetrical imidazolium salts were obtained from the natural chiral pool of (1R,2S,5R)-(?)-menthol. First 1,3-bis[(1R,2S,5R)-(?)-menthoxymethyl]imidazolium chloride, which is a prototype for ionic liquids, was prepared with the use of two different methods. Furthermore, metathesis of this symmetrical imidazolium chloride with various salts was carried out. The ion exchange reaction goes smoothly, with the satisfactory yield of 97.5 to 99.5%. Obtained 1,3-bis[(1R,2S,5R)-(?)-menthoxymethyl]imidazolium salts are stable in the air, in contact with water and in commonly used organic solvents. Moreover they are non-volatile and non-flammable. Discussed symmetrical salts belong to chiral ionic liquids (CILs) where the chirality resided in the cation and is associated with the presence of optically active (1R,2S,5R)-(?)-menthol. The diastereotopic protons in the 1H NMR were thoroughly described. Moreover, the 1H NMR and 13C NMR spectra indicated notable differences in the chemical shifts depending on the anion used. Comparing the differences between values of the chemical shifts, the anions were ordered according to their increasing shielding capacities. The changing of the electron density surrounding the imidazolium ring was discussed.
Influence of the alkyl side chain length on the thermophysical properties of chiral ionic liquids with a (1R,2S,5R)-(–)-menthol substituent and data analysis by means of mathematical gnostics
Andresová, Adéla,Bendová, Magdalena,Schwarz, Jaroslav,Wagner, Zdeněk,Feder-Kubis, Joanna
, p. 336 - 348 (2017/07/22)
A comprehensive physico-chemical characterization of the chiral ionic liquids of a 3-alkyl-1-[(1R,2S,5R)-(–)-menthoxymethyl]imidazolium bis(trifluoromethylsulfonyl)imides homologous series with a linear alkyl substituent ranging from the methyl up to the
Synthesis of inexpensive chiral half-sandwich nickel N-heterocyclic carbene complexes: X-ray diffraction study of the D-menthyl-functionalized complex [Ni(iPr2Ph-NHC-CH2OMent)ClCp]
Rocquin, Mansuy,Ritleng, Vincent,Barroso, Sónia,Martins, Ana M.,Chetcuti, Michael J.
, p. 57 - 62 (2018/03/27)
The imidazolium salts, 1-(2,4,6-trimethylphenyl)-3-[(1R,2S,5R)-(?)-menthoxymethyl]imidazolium chloride (Mes-NHC-CH2OMent·HCl) (1a) and 1-(2,6-diisopropylphenyl)-3-[(1R,2S,5R)-(?)-menthoxymethyl]imidazolium chloride (iPr2Ph-NHC-CH2OMent·HCl) (1b), are readily accessible from inexpensive (1R,2S,5R)-(?)-menthol. They react with nickelocene to give two new chiral nickel-N-heterocyclic carbene (NHC) complexes, [Ni(Mes-NHC-CH2OMent)ClCp] (2a) and [Ni(iPr2Ph-NHC-CH2OMent)ClCp] (2b), in good yields. The new complexes were fully characterized by standard spectroscopic techniques and by a single crystal X-ray diffraction study on complex 2b. Complex 2b crystallizes in the chiral spacegroup P1, with two independent molecules in the unit cell, which are slightly different from each other. Preliminary studies show that these complexes are effective catalysts for the hydrosilylation of ketones. However no chiral induction was observed.
Alcohol, Aldehyde, and Ketone Liberation and Intracellular Cargo Release through Peroxide-Mediated α-Boryl Ether Fragmentation
Hanna, Ramsey D.,Naro, Yuta,Deiters, Alexander,Floreancig, Paul E.
supporting information, p. 13353 - 13360 (2016/10/22)
α-Boryl ethers, carbonates, and acetals, readily prepared from the corresponding alcohols that are accessed through ketone diboration, react rapidly with hydrogen peroxide to release alcohols, aldehydes, and ketones through the collapse of hemiacetal intermediates. Experiments with α-boryl acetals containing a latent fluorophore clearly demonstrate that cargo can be released inside cells in the presence of exogenous or endogenous hydrogen peroxide. These experiments show that this protocol can be used for drug activation in an oxidative environment without generating toxic byproducts.
Synthesis of chiral menthoxymethyl ether of phenol and substituted phenol and their use in directed ortho metalation
Mumtaz, Salma,Khan, Sher Wali,Zaidi, Javid H.,Iqbal, Anila,Cheema, Zain Maqsood,Khan, Khalid Mohammed,Perveen, Shahnaz
, p. 578 - 583 (2014/01/06)
Synthesis of chiral acetals of phenol and bromophenol was carried out using (-) menthol as a pure chiral auxiliary. Metalation of these chiral acetals, followed by nucleophilic attack on different aromatic and aliphatic aldehydes produced chiral products through directed ortho metalation (DoM). Chiral menthoxymethyl (OMen) is developed as a new oxygen based chiral directed metalation group (DMG) for benzene and substituted benzene.
Imidazolium chiral ionic liquid derived carbene-catalyzed conjugate umpolung for synthesis of γ-butyrolactones
Yu, Feng-Li,Jiang, Jia-Jia,Zhao, Dong-Mei,Xie, Cong-Xia,Yu, Shi-Tao
, p. 3996 - 4000 (2013/04/24)
A serial of imidazolium chiral ionic liquids starting from commercially available (-)-menthol as a chiral pool have been synthesized and successfully used for catalyzing conjugate umpolung of α,β-unsaturated aldehydes to stereoselectively synthesize γ-butyrolactones. The catalytic activities of these ionic liquids are examined and compared. The reaction of trans-cinnamaldehyde and p-methoxycarbonyl benzaldehyde as a model has been investigated in detail, and the reaction conditions have been optimized. Under the selected conditions, the ionic liquid catalyst can catalyze the annulations of trans-cinnamaldehyde with different aromatic aldehydes to afford differently substituted γ-butyrolactones. The recyclability of the ionic liquid catalyst is investigated, and the results have indicated that the catalyst can be recycled six times without obvious activity decreasing.
Expanded substrate scope and improved reactivity of ether-forming cross-coupling reactions of organotrifluoroborates and acetals
Vo, Cam-Van T.,Mitchell, T. Andrew,Bode, Jeffrey W.
supporting information; experimental part, p. 14082 - 14089 (2011/10/12)
Mixed acetals and organotrifluoroborates undergo BF3· OEt2-promoted cross-couplings to give dialkyl ethers under simple, mild conditions. A survey of reaction partners identified a hydroxamate leaving group that improves the regioselectivity and product yield in the BF 3·OEt2-promoted coupling reaction of mixed acetals and potassium alkynyl-, alkenyl-, aryl- and heteroaryltrifluoroborates to access substituted dialkyl ethers. This leaving group enables the reaction to proceed rapidly under mild conditions (0 °C, 5-60 min) and permits reactions with electron-deficient potassium aryltrifluoroborates that are less reactive with other acetal substrates. A study of the reaction mechanism and characterization of key intermediates by NMR spectroscopy and X-ray crystallography identified a role for the hydroxamate moiety as a reversible leaving group that serves to stabilize the key oxocarbenium intermediate and the need for a slight excess of organodifluoroborane to serve as a catalyst. A secondary role for the boron nucleophile as an activating ligand was also considered. These studies provide the basis for a general class of reagents that lead to dialkyl ethers by a simple, predictable cross-coupling reaction.
3-Alkoxymethyl-1-(1R,2S,5R)-(-)-menthoxymethylimidazolium salts-based chiral ionic liquids
Feder-Kubis, Joanna,Kubicki, MacIej,Pernak, Juliusz
experimental part, p. 2709 - 2718 (2011/02/16)
A new group of imidazolium salt-based chiral ionic liquids have been prepared and characterized. The chiral ionic liquids obtained are stable in air, in contact with water and popular organic solvents. Their physicochemical properties, single-crystal X-ray structures, antimicrobial activities, and antielectrostatic effects have been determined. The chiral ionic liquids synthesized have proven to represent not only potential new solvents in asymmetric synthesis but also effective disinfectants with antielectrostatic activity.
