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101.
Jakub Iwanejko Elżbieta Wojaczyńska Justyna Trynda Magdalena Maciejewska Joanna Wietrzyk Andrzej Kochel Jacek Wojaczyński 《Tetrahedron》2017,73(16):2276-2282
Tests of antiproliferative activity of Mannich adducts of aromatic nucleophiles and a chiral bicyclic imine revealed a di-tert-butylphenol derivative as a promising compound for further exploration. To study the influence of substitution pattern and a configuration of stereogenic centers on the inhibition of cancer cell growth, a series of Mannich bases were obtained with a good to high diastereoselectivity from the reaction of the imine and three isomeric di-tert-butylphenols. Six new enantiopure adducts were isolated and fully characterized. Selected derivatives were shown to exhibit an interesting antiproliferative activity comparable to cisplatin. 相似文献
102.
Vittorio Saggiomo 《Tetrahedron letters》2009,50(32):4663-1961
The reaction of aniline with aryl aldehydes in water has been investigated in the past, but contradictory results have been published. While only small amounts of imines 3 were detected by NMR analysis, isolation afforded high imine yields. A reinvestigation of the reaction of benzaldehyde (1a) and salicylaldehyde (1b) with aniline (2) revealed two important factors which explain the putative contradiction: (i) NMR only reveals the fraction of products which is soluble in water, and (ii) imines 3 form during or after workup. 相似文献
103.
《Tetrahedron letters》2004,45(4):719-722
A stereodivergent synthesis of 1,4-dideoxy-1,4-imino-d-mannitol I and d-allitol III from an (S)-glyceraldimine, which is easily prepared from d-mannitol, has been achieved with overall yields of 62% and 49%, respectively. The synthesis is based on the addition of vinylmagnesium bromide to N-benzylimine 1, derived from readily available (R)-2,3-O-isopropylideneglyceraldehyde, followed by N-allylation or N-acryloylation, ring-closing metathesis and asymmetric dihydroxylation. 相似文献
104.
Anna Rozycka Michal Filapek Natalia Gorska Krzysztof Artur Bogdanowicz Paweł Dabczynski 《Liquid crystals》2018,45(6):831-843
Two bent-shaped imines (9E)-N-(3-((E)-(4-hexadecylphenylimino)methyl)benzylidene)-4-hexadecylbenzenamine (SL1) and (10E)-N-(3-((E)-(4-(perfluorooctyl)phenylimino)methyl)benzylidene)-4-(perfluorooctyl)benzenamine (SL2) were prepared by condensation reaction in N,N-dimethylacetamide to study their thermal, structural and electrochemical properties, as well as their mixtures with titanium dioxide. Chemical structure, temperature and TiO2 influences on the phase transition temperatures, enthalpy, texture and molecular dynamics of both imines were investigated by differential scanning calorimetry, polarising optical microscopy and Fourier transform middle-infrared absorption spectroscopy during heating and cooling. Changes in the surface morphology of the imines and their mixtures with TiO2 were registered by atomic force microscopy. X-ray study showed the tendency to form lamellas in the case of SL2 as an effect of the presence of two terminal perfluorinated alkyl chains connected to a polar mobile aromatic core, which resulted in microsegregation. Additionally, TiO2 influences the energy gap and HOMO–LUMO levels of imines as was detected by cyclic voltammetry. Finally, devices with two types of architectures, such as ITO/TiO2/SL1(or P3HT)/Au and ITO/TiO2/SL1:P3HT/Au were constructed and investigated under irradiation intensity of 97.7 mW/cm2. 相似文献
105.
The simple thermal addition product of N,N-dimethyltrimethylsilylamine with 2,2,2-trifluoroacetophenone provides a shelf-stable reagent for nucleophilic trifluoromethylation of both the carbonyl and the imine group. 相似文献
106.
Cycloaddition Reactions of Trifluoromethyl Isocyanide with Diphosphenes. Synthesis and Structure of the new 2-Phosphinidene-1,3-azaphospholidine Derivative [2 + 1] Cycloaddition reactions of trifluoromethyl isocyanide 1 and methylisocyanide 2 with the diphosphene R? P?P? R 3a ( a R ? C[Si(CH3)3]3) yield the three membered heterocyclic diphosphirane imines 4 and 5 , respectively. Whereas the trifluoromethyl substituted compound 4 is thermally very stable, the methylsubstitued derivative 5 slowly looses methyl isocyanide reforming the diphosphene 3a . In the reaction of 1 with R? P?P? R 3b [ b R = 2,4,6-(t-Bu)3C6H2] no evidence for the formation of a three membered ring compound could be obtained. The five membered heterocycle 3-(2,4,6-Tri-t-butylphenyl)-2-[2,4,6-tri-t-butylphenyl)-phosphinidene]-1-trifluoromethyl-4, 5-bis(trifluoromethylimin)-1,3-azaphospholidine 6 was isolated as the only product together with unreacted 3b . The structure of 6 , triclinic, P1 , a = 1081.1(8), b = 1463.1(11), c = 1643.6(5)pm, α = 64.01(6), β = 81.22(4), γ = 74.04(5)°, Z = 2, R = 0.080, Rw = 0.085, has been elucidated by X-ray diffraction. 相似文献
107.
Christiane M. Bode 《Tetrahedron》2006,62(49):11499-11505
Cinchona alkaloid-derived thiourea catalysts promote nucleophilic additions to acyl imines for the asymmetric synthesis of secondary amine adducts. The hydroquinine-derived thiourea catalyst efficiently promotes the aza-Henry reaction of nitroalkane with acyl imines, affording β-nitroamines in good yields with enantioselectivities of 90-98% ee and diastereoselectivities up to 97%. The scope of the reaction also includes dimethyl malonate as a nucleophile to access β-amino esters in high enantiopurity. Under the optimized reaction conditions, secondary amine adducts of high enantiopurity are generated based on various aromatic and α,β-unsaturated acyl imines. 相似文献
108.
A CAN-initiated aza-Diels-Alder reaction for a facile synthesis of 4-amido-N-yl tetrahydroquinolines
Cycloaddition of N-arylimines with N-vinylpyrrolidin-2-one or N-methyl-N-vinylacetamide was efficiently initiated by cerium(IV) ammonium nitrate (CAN), and produced stereoselectively the corresponding 2,4-cis-4-amido-N-yl tetrahydroquinoline derivatives in good yields. 相似文献
109.
A novel catalytic system, silane/MoO2Cl2 (10 mol %), for the reduction of imines in excellent to moderate yields and chemoselectivity was designed. These results extend the scope of the use of MoO2Cl2 as an effective catalyst for reduction reactions. 相似文献
110.
Manabu Yasumoto 《Journal of fluorine chemistry》2007,128(7):736-739
This paper describes a synthesis of α-(trifluoromethyl)benzylamine via a novel base-free biomimetic reductive amination of α,α,α-trifluoroacetophenone with benzylamine. When the corresponding imine, derived from α,α,α-trifluoroacetophenone and benzylamine was heated at 200 °C under N2 for 1 day, the thermal 1,3-proton shift reaction took place giving rise to the N-(benzylidene)-α-(trifluoromethyl)benzylamine in quantitative yield. This thermal 1,3-proton shift reaction was used a key step in the development of new and substantially simplified, practical and operationally convenient procedure for preparation of the target α-(trifluoromethyl)benzylamine on large scale. 相似文献