3395-81-1Relevant academic research and scientific papers
Practical acetalization and transacetalization of carbonyl compounds catalyzed by recyclable PVP-I
Cao, Fu-Rong,Lu, Guangying,Ren, Jiangmeng,Wang, Di,Zeng, Bu-Bing
, (2021/06/21)
A novel PVP-I catalyzed acetalizations/transacetalizations of carbonyl compounds has been developed processing with a mild and easy handling fashion. Different types of Acyclic and cyclic acetals were prepared from carbonyl compounds or their acetals successfully. Further applications of newly developed catalytic combination were testified. This protocol featured with simplicity of operation, mild reaction condition, short reaction time, recyclable of catalyst and broad substrates scope with excellent yields.
Thiol-initiated photocatalytic oxidative cleavage of the C=C bond in olefins and its extension to direct production of acetals from olefins
Wang, Xinglin,Li, Yuanyuan,Li, Zhaohui
, p. 1000 - 1006 (2021/02/26)
The oxidative cleavage of olefins to produce aldehydes/ketones is an important reaction in organic syntheses. In this manuscript, a mild and operationally simple protocol for the aerobic oxidation of olefins to produce carbonyl compounds was realized over ZnIn2S4under visible light, using air as the oxidant and a thiol as the initiator. It was proposed that the photogenerated holes over ZnIn2S4attack the thiol to produce thiyl radicals, which initiate the oxidative cleavage of the C=C bond in olefins to produce aldehydes/ketones. By further coupling with the condensation between the as-obtained aldehydes/ketones and alcohols, this strategy can also be applied to the production of different acetals directly from the olefins. This study demonstrates a new pathway to realize the oxidative cleavage of olefins to produce aldehydes/ketones, and also provides a new protocol for the production of acetals directly from the olefins.
Systematic Study of Regioselective Reductive Ring-Opening Reactions of 4,6- O-Halobenzylidene Acetals of Glucopyranosides
Mez?, Erika,Herczeg, Mihály,Demeter, Fruzsina,Bereczki, Ilona,Csávás, Magdolna,Borbás, Anikó
, p. 12973 - 12987 (2021/09/18)
Reductive openings of cyclic acetals are widely used in modern synthetic organic chemistry for the regioselective introduction of protecting groups. A systematic study was performed on the applicability and efficacy of various hydride donor and protic or Lewis acid reagent combinations in the reductive ring opening of glucosidic 4,6-halobenzylidene acetals bearing an ortho-, meta-, and para-chloro- or -bromo substituent on the benzene ring. Most of the reagent combinations tested cleaved the 4,6-O-halobenzylidene acetal rings at O4 or O6 efficiently and with the expected regioselectivity. The LiAlH4-AlCl3 and the BH3·THF-TMSOTf combinations produced the 4-O-halobenzyl ether/6-OH products with complete regioselectivity and high yields. The use of Me3N·BH3-AlCl3 reagent system in toluene was also effective in cleaving the acetal ring at O6 but was accompanied by Al-chelation-assisted debenzylation side reactions. The NaCNBH3-HCl and the Et3SiH-BF3·Et2O combinations were highly effective in yielding the 6-halobenzyl ether/4-OH derivatives. Et3SiH, in combination with TfOH, produced the 6-O-ether/4-OH products in rapid reactions but also triggered silylation and reductive halobenzylation as secondary transformations. Reductive opening of the 1,3-dioxane ring of pyranosidic 4,6-O-halobenzylidene acetals by the proper reagent combination was found to be an efficient method for the regioselective introduction of versatile halobenzyl protecting groups onto the pyranose ring.
Photochemical synthesis of acetals utilizing Schreiner's thiourea as the catalyst
Kokotos, Christoforos G.,Nikitas, Nikolaos F.,Spiliopoulou, Nikoleta
supporting information, p. 3539 - 3545 (2020/06/25)
Acetalization of aldehydes is an area of great importance in Organic Chemistry for both synthetic and biological puproses. Herein, we report a mild, inexpensive and green photochemical protocol, where Schreiner's thiourea (N,N′-bis[3,5-bis(trifluoromethyl)-phenyl]-thiourea) is utilized as the catalyst and cheap household lamps as the light source. A variety of aromatic and aliphatic aldehydes were converted into acetals in good to high yields (23 examples, 36-96% yield) and an example of the synthesis of a cyclic acetal is provided. The reaction mechanism was also studied.
Synthesis, structural determination and catalytic study of a new 2-D chloro-substituted zinc phosphate, (C8N2H20)[ZnCl(PO3(OH))]2
Rayes, Ali,Herrera, Raquel P,Moncer, Manel,Ara, Irene,Calestani, Gianluca,Ayed, Brahim,Mezzadri, Francesco
, (2019/11/03)
A novel chloro-substituted zinc-phosphate, (C8N2H20)[ZnCl(PO3(OH))], has been synthesized by a slow evaporation method in the presence of 1,3-cyclohexanebis- (methylamine), which acts as a template. The structure consists of vertex linked ZnO3Cl and PO3(OH) tetrahedral, assembled into corrugated porous layers [ZnCl(PO3(OH))2]∞ with (4.82) topology. The optical properties were also investigated using Diffuse Reflecting Spectroscopy (DRS), showing that the title compound has semiconducting properties. In addition, the catalytic activity of (C8N2H20)[ZnCl(PO3(OH))]2 has been tested in the acetalisation reaction of aldehydes. The title compound displayed a high catalytic activity with practically total conversion in many examples using MeOD as solvent and as the sole source of acetalisation. More importantly, the reaction crudes are very clean and only the preferred products are found in the NMR spectra.
Amino acid derivative, feed composition and application thereof
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Paragraph 0121-0125, (2020/05/14)
The invention provides an amino acid derivative, a feed composition and application thereof, and belongs to the technical field of animal feed additives. The amino acid derivative is a compound with astructure shown as a formula (I), and a stereoisomer, a tautomer, a solvate, a metabolite, a feed acceptable salt or a prodrug thereof. In formula (I) shown in the specification, Z is a C1-C3 alkylene group. X is an indole ring group with a structure shown as a formula (II). The formula (II) is shown in the specification, wherein Y is phenyl with the structure shown in the formula (III) shown inthe specification. The amino acid derivative is used as an animal feed additive, and can promote the growth of animals and improve the feed conversion.
Photo-organocatalytic synthesis of acetals from aldehydes
Nikitas, Nikolaos F.,Triandafillidi, Ierasia,Kokotos, Christoforos G.
supporting information, p. 669 - 674 (2019/02/14)
A mild and green photo-organocatalytic protocol for the highly efficient acetalization of aldehydes has been developed. Utilizing thioxanthenone as the photocatalyst and inexpensive household lamps as the light source, a variety of aromatic and aliphatic aldehydes have been converted into acyclic and cyclic acetals in high yields. The reaction mechanism was extensively studied.
Nickel-Catalyzed Chemoselective Acetalization of Aldehydes With Alcohols under Neutral Conditions
Subaramanian, Murugan,Landge, Vinod G.,Mondal, Akash,Gupta, Virendrakumar,Balaraman, Ekambaram
supporting information, p. 4557 - 4562 (2019/08/30)
A molecularly defined NiII-complex catalyzing the chemoselective acetalization of aldehydes with alcohols under neutral conditions is reported. The reaction is general, efficient and showed a wide substrate scope (including aliphatic aldehydes) as well as excellent functional group tolerance. Reusability of the present nickel catalyst is also demonstrated.
Ce(III)-Based frameworks: From 1d chain to 3d porous metal-organic framework
Derakhshandeh, Parviz Gohari,Abednatanzi, Sara,Leus, Karen,Janczak, Jan,Van Deun, Rik,Van Der Voort, Pascal,Van Hecke, Kristof
, p. 7096 - 7105 (2019/11/19)
The reaction of pyridine-2,4-dicarboxylic acid (2,4-H2 pydc) with Ce(NO3)36H2O, by applying only minor changes to the reaction conditions, generated a series of new one-, two-, and three-dimensional (1D, 2D, and 3D) coordination polymers, namely, [Ce(pydc)(Hpydc)(H2O)4]n (1), [Ce(pydc)(Hpydc)(H2O)2]n (2), and {[Ce3(pydc)4(H2O)2NO3]4H2O}n (3). The ancillary ligand interaction as well as the reaction conditions determine the specific coordination modes for the Hpydc- and pydc2- ligands and, in turn, discriminate between 1D, 2D, and 3D frameworks. Characterization of the prepared materials was performed using single-crystal and powder X-ray diffraction analysis, Fourier transform infrared spectroscopy, CHN elemental analysis, thermogravimetric analysis, and nitrogen adsorption/desorption techniques. Compound 1 consists of 1D chains, that compose of Ce3+ ions bridged by Hpydc- and pydc2- ligands, which further link via noncovalent interactions to form a 3D supramolecular architecture. Compound 2 assembles into 2D sheets with 1D channels. Similarly, via hydrogen-bonding interactions between two adjacent sheets, the 2D layers are further stacked into the final 3D supramolecular structure. Compound 3 is a 3D metal-organic framework (MOF), showing 1D helical channels. The progressive skeletal variation from the 1D chains (1) to 2D sheets (2) and 3D framework (3) is attributed to the flexibility of both the Ce(III) coordination sphere and coordination modes of the Hpydc- and pydc2- ligands under different reaction conditions. The three compounds illustrate how the tuning of the coordination geometry of Ce(III) translates into different dimensionality, which is readily influenced by reaction temperature and ancillary ligand presence. Moreover, the porosity of MOF 3 was confirmed by N2 and CO2 gas adsorption/desorption. Finally, the catalytic activity of MOF 3 was examined in acetalization reactions in a series of aromatic aldehydes with methanol.
Remote ‘Imidazole’ Based Ruthenium(II) p-Cymene Precatalyst for Selective Oxidative Cleavage of C?C Multiple Bonds
Dutta, Manali,Bania, Kusum Kumar,Pratihar, Sanjay
, p. 2683 - 2694 (2019/05/24)
The dual role of remote ‘imidazole’ attached with the precatalyst [(p-cymene)RuII(L)Y]+ (L=2-(4-substituted-phenyl)-1H-imidazo[4,5-f][1,10] phenanthroline, Y=chloride/solvent) was explored for the selective oxidative cleavage of C?C multiple bonds to acetals/aldehydes. The presence of ‘imidazole’ in the precatalysts was found to be useful for the activation of oxidant and release of p-cymene from the precatalysts, which in turn was not effective without the ‘imidazole’ moiety. The mechanistic aspects of the precatalyst were evaluated from spectroscopic, kinetic, and few other controlled experiments. The loss of p-cymene is the key step for the reaction and found to be faster in solvated precatalyst, [(p-cymene)RuII(L)(MeOH)]++ and thus showed 3–4-fold more effective as compared to [(p-cymene)RuII(L)Cl]+.
