20225-24-5Relevant academic research and scientific papers
Preparation method of 2-R1 valeric acid
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, (2021/07/24)
The invention discloses a preparation method for 2-R1 valeric acid. The preparation method comprises the following steps: step 1, with methyl cyanoacetate as a starting material, adding bromopropane and sodium methoxide, carrying out a catalytic reaction, and conducting purifying to obtain 2-cyanomethyl valerate; step 2, subjecting 2-cyanomethyl valerate to a reaction under the catalysis of iodoalkane and sodium methoxide, and conducting aftertreatment to obtain 2-cyano-2-R1 methyl valerate; step 3, enabling the 2-cyano-2-R1 methyl valerate to undergo a reaction in an aqueous solution of sulfuric acid at 120-160 DEG C for 15-40 hours so as to obtain a mixture of 2-R1 valeric acid and 2-R1 methyl valerate; and step 4, hydrolyzing the mixture by using an aqueous sodium hydroxide solution to obtain 2-R1 sodium valerate and methanol, and conducting acidifying by using inorganic acid to obtain 2-R1 valeric acid. Reagents adopted in the preparation method are relatively common, and the risk of the reagents is relatively low; and reaction conditions are mild, and the temperature is easier to control relatively. The invention develops a purification process of the key intermediate 2-cyanomethyl valerate, and the process flow is simple.
Ruthenium-catalysed hydroxycarbonylation of olefins
Dühren, Ricarda,Kucmierczyk, Peter,Jackstell, Ralf,Franke, Robert,Beller, Matthias
, p. 2026 - 2030 (2021/04/09)
State-of-the-art catalyst systems for hydroxy- and alkoxycarbonylations of olefins make use of palladium complexes. In this work, we report a complementary ruthenium-catalysed hydroxycarbonylation of olefins applying an inexpensive Ru-precursor (Ru3(CO)12) and PCy3as a ligand. Crucial for the success of this transformation is the use of hexafluoroisopropanol (HFIP) as the solvent in the presence of an acid co-catalyst (PTSA). Overall, moderate to good yields are obtained using aliphatic olefins including the industrially relevant substrate di-isobutene. This atom-efficient catalytic transformation provides straightforward access to various carboxylic acids from unfunctionalized olefins.
Mild C-H functionalization of alkanes catalyzed by bioinspired copper(ii) cores
Kirillova, Marina V.,Fernandes, Tiago A.,André, Vania,Kirillov, Alexander M.
supporting information, p. 7706 - 7714 (2019/08/30)
Three new copper(ii) coordination compounds formulated as [Cu(H1.5bdea)2](hba)·2H2O (1), [Cu2(μ-Hbdea)2(aca)2]·4H2O (2), and [Cu2(μ-Hbdea)2(μ-bdca)]n (3) were generated by aqueous medium self-assembly synthesis from Cu(NO3)2, N-butyldiethanolamine (H2bdea) as a main N,O-chelating building block and different carboxylic acids [4-hydroxybenzoic (Hhba), 9-anthracenecarboxylic (Haca), or 4,4′-biphenyldicarboxylic (H2bdca) acid] as supporting carboxylate ligands. The structures of products range from discrete mono- (1) or dicopper(ii) (2) cores to a 1D coordination polymer (3), and widen a family of copper(ii) coordination compounds derived from H2bdea. The obtained compounds were applied as bioinspired homogeneous catalysts for the mild C-H functionalization of saturated hydrocarbons (cyclic and linear C5-C8 alkanes). Two model catalytic reactions were explored, namely the oxidation of hydrocarbons with H2O2 to a mixture of alcohols and ketones, and the carboxylation of alkanes with CO/S2O82- to carboxylic acids. Both processes proceed under mild conditions with a high efficiency and the effects of different parameters (e.g., reaction time and presence of acid promoter, amount of catalyst and solvent composition, substrate scope and selectivity features) were studied and discussed in detail. In particular, an interesting promoting effect of water was unveiled in the oxidation of cyclohexane that is especially remarkable in the reaction catalyzed by 3, thus allowing a potential use of diluted, in situ generated solutions of hydrogen peroxide. Moreover, the obtained values of product yields (up to 41% based on alkane substrate) are very high when dealing with the C-H functionalization of saturated hydrocarbons and the mild conditions of these catalytic reactions (50-60 °C, H2O/CH3CN medium). This study thus contributes to an important field of alkane functionalization and provides a notable example of new Cu-based catalytic systems that can be easily generated by self-assembly from simple and low-cost chemicals.
Three-component 1D and 2D metal phosphonates: structural variability, topological analysis and catalytic hydrocarboxylation of alkanes
Demadis, Konstantinos D.,Anagnostou, Zafeiria,Panera, Aggeliki,Mezei, Gellert,Kirillova, Marina V.,Kirillov, Alexander M.
, p. 17788 - 17799 (2017/03/30)
Herein, we report the use of diphosphonate building blocks and chelating auxiliary N,N-ligands to generate novel polymeric architectures. Specifically, we report new 1D and 2D coordination polymers incorporating three components: transition metal ions (Co2+, Cu2+, Mn2+ or Zn2+), diphosphonate ligands (methane-diphosphonate, MDPA, or 1,2-ethanediphosphonate, EDPA) and N,N-heterocyclic chelators (1,10-phenanthroline, phen, or 2,2′-bipyridine, bpy). Six compounds were isolated under mild synthesis (ambient temperature) conditions: [Cu2(phen)2(EDPA)2(H2O)4]∞ (1), [Co(phen)(EDPA)(H2O)2]∞ (1a), {[Cu(phen)(MDPA)]·H2O]}∞ (2), [Mn(bpy)(EDPA)(H2O)2]∞ (3), [Zn(bpy)(EDPA)]∞ (4), and, lastly, a discrete Ni2+ molecular derivative [Ni(phen)(H2O)4](EDPA) (5). Synthetic details, crystal structures, and intermolecular interactions (π-π stacking and hydrogen bonding) in 1-5 are discussed. Topological analyses and classification of the underlying metal-organic networks in 1-4 were performed, revealing the uninodal 1D chains with the 2C1 topology in 1-3 and the binodal 2D layers with the 3,4L13 topology in 4. In 1-3 and 5, multiple hydrogen bonds lead to the extension of the structures to give 3D H-bonded nets with the seh-4,6-C2/c topology in 1 and 3, 2D H-bonded layers with the 3,5L52 topology in 2, and a 3D H-bonded net with the 6,6T1 topology in 5. The catalytic activity of compounds 1 and 1a was evaluated in a single-step hydrocarboxylation of cyclic and linear C5-C8 alkanes to furnish the carboxylic acids with one more carbon atom. These reactions proceed in the presence of CO, K2S2O8, and H2O at 60 °C in MeCN/H2O medium. Compound 1 showed higher activity than 1a and was studied in detail. Substrate scope was investigated, revealing that cyclohexane and n-pentane are the most reactive among the cyclic and linear C5-C8 alkanes, and resulting in the total yields of carboxylic acids (based on substrate) of up to 43 and 36%, respectively. In the case of cycloalkane substrates, only one cycloalkanecarboxylic acid is produced, whereas a series of isomeric monocarboxylic acids is generated when using linear alkanes; an increased regioselectivity at the C(2) position of the hydrocarbon chain was also observed.
Structurally well-characterized new multinuclear Cu(II) and Zn(II) clusters: X-ray crystallography, theoretical studies, and applications in catalysis
Ansari, Istikhar A.,Sama, Farasha,Raizada, Mukul,Shahid,Ahmad, Musheer,Siddiqi, Zafar A.
supporting information, p. 9840 - 9852 (2016/11/11)
Two new trinuclear Cu(ii) and dinuclear Zn(ii) clusters are crystallized out by reacting the metal salts with the triethanolamine (H3tea) ligand in the presence of benzoic acid (Hba). The complexes are characterized by elemental, thermal, magnetic, spectral (FTIR, UV-Visible, EPR, and photoluminescence) and single crystal X-ray studies. Single crystal X-ray crystallography reveals the composition of the complexes to be [Cu3(H2tea)2(ba)2(NO3)2] (1) and [Zn2(H2tea)(ba)3]H2O (2). FTIR ascertains the binding modes of H2tea-, ba- and NO3-. Triethanolamine binds in both the complexes in the monoanionic (H2tea-) mode. ba- is present as an anchoring auxiliary to generate di- and trinuclear clusters. The Cu(ii) ion is present as a distorted octahedral center in the Cu3 cluster (1), while the two Zn(ii) ions in 2 have been reported for the first time to possess distorted octahedral as well as tetrahedral geometry in the same molecule. The intriguing features of the non-covalent supramolecular interactions have been investigated and supported theoretically by using Hirshfeld surface analysis and ab initio methods. The solid state photoluminescence (PL) spectra of 1 and 2 disclose the luminescence property of the complexes. Due to the closed or nearly closed shell configuration (d9 or d10), the present complexes are screened for catalytic properties in the hydrocarboxylation of alkanes and cycloalkanes. The catalytic activity data are indicative of the potential catalytic properties of 1 and 2.
Enzyme cascade reactions: Synthesis of furandicarboxylic acid (FDCA) and carboxylic acids using oxidases in tandem
McKenna, Shane M.,Leimkühler, Silke,Herter, Susanne,Turner, Nicholas J.,Carnell, Andrew J.
supporting information, p. 3271 - 3275 (2015/06/25)
A one-pot tandem enzyme reaction using galactose oxidase M3-5 and aldehyde oxidase PaoABC was used to convert hydroxymethylfurfural (HMF) to the pure bioplastics precursor FDCA in 74% isolated yield. A range of alcohols was also converted to carboxylic acids in high yield under mild conditions.
Palladium Complexes with Bulky Diphosphine Ligands as Highly Selective Catalysts for the Synthesis of (Bio-) Adipic Acid from Pentenoic Acid Mixtures.
Low, Choon Heng,Nobbs, James D.,Van Meurs, Martin,Stubbs, Ludger P.,Drent, Eite,Aitipamula, Srinivasulu,Pung, Michelle H. L.
, p. 4281 - 4292 (2015/09/22)
A series of sterically bulky diphosphines have been prepared, including P2 = trans-1,2-bis[(di-tert-butylphosphino)methyl]cyclohexane (4), (2-methylenepropane-1,3-diyl)bis(di-tert-butylphosphine) (5), bis[(di-tert-butylphosphino)methyl]dimethylsilane (6), and cis- and trans-11,12-bis[(di-tert-butylphosphino)methyl]-9,10-dihydro-9,10-ethanoanthracene (10 and 11). The corresponding palladium complexes of these ligands, P2Pd(CF3CO2)2, have been synthesized and characterized. The solid-state structures of [Pd(4)(CF3CO2)2], [Pd(5)(CF3CO2)2], [Pd(6)(CF3CO2)2], and [Pd(11)(CF3CO2)2] were obtained by single-crystal X-ray diffraction and confirm the bidentate binding mode of the ligand and a square-planar coordination geometry with a minor distortion from the ideal. The diphosphines in combination with Pd(OAc)2 have been applied in the hydroxycarbonylation of a mixture of pentenoic acid isomers to produce adipic acid with high selectivity (in several cases >95%). The (regio)selectivity of the hydroxycarbonylation reaction is highly dependent on the P2 diphosphine ligand structure, particularly the steric bulk of the substituents on the diphosphine donor and the P-Pd-P bite angle in the complexes, with respectively tertiary alkyl phosphine substituents (tert-butyl, adamantyl) and a C4 backbone P-Pd-P bite angle >100° being the common features of highly adipic acid selective systems. It is suggested that the regioselectivity of hydroxycarbonylation becomes largely driven by the chelation of the carboxylic acid functionality of pentenoic acid substrates, when smaller size P substituents and/or when P2 ligands with smaller bite angles (100°) are applied.
How to force a classical chelating ligand to a metal non-chelating bridge: The observation of a rare coordination mode of diethanolamine in the 1D complex {[Cu2(Piv)4(H3tBuDea)](Piv)}n
Nesterova, Oksana V.,Kirillova, Marina V.,Guedes Da Silva, M. Fatima C.,Boca, Roman,Pombeiro, Armando J. L.
, p. 775 - 783 (2014/01/17)
The novel chain coordination polymer {[Cu2(Piv) 4(H3tBuDea)](Piv)}n (1) has been prepared through the self-assembly reaction of copper(ii) nitrate with pivalic acid (HPiv) and N-tert-butyldiethanolamine (H2tBuDea) in acetonitrile solution. Crystallographic analysis revealed the extremely rare non-chelating bridging coordination mode of diethanolamine ligand in 1, observed for the first time in transition metal complexes, as well as in complexes of diethanolamine having a non-coordinating aliphatic group at the N atom. Possible reasons for such a coordination and analysis of the main coordination modes of diethanolamine-based ligands are discussed. Variableerature (1.8-300 K) magnetic susceptibility measurements showed that 1 represents a rare example of dicopper(ii) tetracarboxylate that is a diamagnetic solid at room temperature. This behaviour is compared with literature examples and discussed on the basis of DFT calculations. Furthermore, 1 acts as an efficient catalyst for the mild hydrocarboxylation of linear and cyclic C5-C8 alkanes into the corresponding carboxylic acids.
Carbon dioxide as a C1 building block for the formation of carboxylic acids by formal catalytic hydrocarboxylation
Ostapowicz, Thomas G.,Schmitz, Marc,Krystof, Monika,Klankermayer, Juergen,Leitner, Walter
, p. 12119 - 12123 (2013/12/04)
A happy marriage of two processes: An effective catalytic system was identified for the direct synthesis of carboxylic acids from non-activated olefins or alcohols, CO2, and H2. Detailed analysis together with labeling studies indicated that the overall hydrocarboxylation of simple olefins results from a combination of the reverse water-gas shift (rWGS) reaction and a hydroxycarbonylation step, each promoted by a rhodium catalyst (see scheme). Copyright
Tautomeric effect of hydrazone Schiff bases in tetranuclear Cu(ii) complexes: Magnetism and catalytic activity towards mild hydrocarboxylation of alkanes
Sutradhar, Manas,Kirillova, Marina V.,Guedes Da Silva, M. Fatima C.,Liu, Cai-Ming,Pombeiro, Armando J. L.
, p. 16578 - 16587 (2013/12/04)
Three new tetranuclear copper(ii) complexes [Cu(HL1)] 4·4EtOH (1·4EtOH), [Cu(HL2)]4 (2) and [Cu(H2L3)]4(NO3) 4·2H2O (3·2H2O) have been synthesized using three different hydrazone Schiff base ligands derived from the condensation of the aromatic acid hydrazides 2-hydroxybenzo-, 2-aminobenzo- or benzo-hydrazide, with 2,3-dihydroxybenzaldehyde. Complexes 1 and 3 have been characterized by single crystal X-ray diffraction analysis. The coordinating behaviour of the ligand depends on the nature of the ortho substituent present in the hydrazide moiety. The ligands bearing a strong electron donating group (by resonance) in the ortho position undergo complexation via enolization and deprotonation, whereas the absence of such an effect leads to complexation via the keto form, and two different types of tetranuclear Cu(ii) clusters, viz. open-cubane and cubane, are obtained. Variable temperature magnetic susceptibility measurements of complexes 1 and 3 have been carried out to examine the nature of magnetic interaction between the Cu(ii) centres. All the three complexes (1-3) act as good catalyst precursors towards mild hydrocarboxylation of linear and cyclic alkanes into carboxylic acids in water-acetonitrile medium.
