Reaction Of Cinnamaldehyde Research Articles

Modification Structure of Cinnamaldehyde with Primary Amines by Reflux and Sonication Methods in the Presence of Sulfuric Acid as a Catalyst

Cinnamon is one of the most valuable natural resources that sustains life and exists freely in nature. Cinnamaldehyde is the primary compound in cinnamon oil. It has a unique structure that contains a benzene ring, an aldehyde group, and an unsaturated double bond. Cinnamaldehyde has been structurally modified to improve biological activity. In this research, cinnamaldehyde and nitrophenyl amines were reacted with sulfuric acid as a catalyst by refluxing and sonication. UV-Vis Spectroscopy, FT-IR, 1H-NMR, and 13C-NMR were used to validate the chemical structures. Thin-layer chromatography (TLC) revealed a new single spot formed by the reaction of cinnamaldehyde and 4-amino-2-nitrophenol. By refluxing for 2 hours or sonicating for 30 minutes, a novel imine chemical, 4-nitro-2-((3-phenylallylidene)amino)phenol, was effectively synthesized with a yield of 75.21% or 83.71%, respectively. This imine was obtained as a dark red powder with a melting point of 237 °C. Meanwhile, only sonication produced a novel product from the reaction of cinnamaldehyde and 4-nitroaniline. However, the structural elucidation has not yet been performed because the yield was so low. Surprisingly, there was no reaction between cinnamaldehyde and 2,4-dinitroaniline. It was most likely owing to the amine’s bulky structure and the presence of two nitro groups in the amine as electron-withdrawing groups that reduced the nucleophilicity of the amine. We demonstrated that sonication is a suitable approach for imine synthesis, as it is commonly utilized in organic compound synthesis protocols.

Construction of N-Doped Carbon-Modified Ni/SiO2 Catalyst Promoting Cinnamaldehyde Selective Hydrogenation.

At present, the selective hydrogenation of α, β-unsaturated aldehydes remains a challenge due to competition between unsaturated functional groups (C=C and C=O). In this study, N-doped carbon deposited on silica-supported nickel Mott-Schottky type catalysts (Ni/SiO2@NxC) was prepared for the selective hydrogenation of cinnamaldehyde (CAL) by using the respective hydrothermal method and high-temperature carbonization method. The prepared optimal Ni/SiO2@N7C catalyst achieved 98.9% conversion and 83.1% selectivity for 3-phenylpropionaldehyde (HCAL) in the selective hydrogenation reaction of CAL. By constructing the Mott-Schottky effect, the electron transfer from metallic Ni to N-doped carbon at their contact interface was promoted, and the electron transfer was demonstrated by XPS and UPS. Experimental results indicated that by modulating the electron density of metallic Ni, the catalytic hydrogenation of C=C bonds was preferentially performed to obtain higher HCAL selectivity. Meanwhile, this work also provides an effective way to design electronically adjustable type catalysts for more selective hydrogenation reactions.

Ultrasound-assisted multicomponent synthesis of pyrido[2,3-d]pyrimidine derivatives and their DFT calculations: A green approach

Pyrido[2,3-d]pyrimidines with their diverse biological potential became a highly significant class of N-containing heterocyclic compounds. They are prepared by the reaction of cinnamaldehyde and aminopyrimidine with 1,3-diketones (hydroxynaphthaquinone and hydroxycoumarin) by applying a knoevenagel condensation followed by a Michael addition multicomponent procedure. Although a few methods have been developed for synthesizing these compounds, they have advantages and disadvantages. Hence, developing a simple, efficient, and environmentally benign methodology for preparing these molecules in the presence of green reaction conditions is still in great demand. Therefore, this article describes an ultrasound-mediated multicomponent protocol to produce pyrido[2,3-d]pyrimidine under neat conditions. Further geometric optimizations, a frontier molecular orbital approach, and the molecular electrostatic potential for the synthesised chemical 4c and 5a were carried out using a computer density functional investigation. The DFT investigation was conducted using the B3LYP/6-311G (d,P) level of theory as the basis set.

The reaction of cinnamaldehyde and cinnam(o)yl derivatives with thiols

Spurred by the alleged relevance of the thia-Michael reaction in the bioactivity of various classes of cinnam(o)yl natural products and by the development of a quick NMR assay to study this reaction, we have carried out a systematic study of the “native” reactivity of these compounds with dodecanethiol and cysteamine as models, respectively, of simple thiols and reactive protein thiols that can benefit from iminium ion catalysis in Michael reactions. Cinnamoyl esters and amides, as well as cinnamyl ketones and oximes, did not show any reactivity with the two probe thiols, while cinnamaldehyde (1a) reacted with cysteamine to afford a mixture of a thiazoline derivative and compounds of multiple addition, and with aliphatic thiols to give a single bis-dithioacetal (6). Chalchones and their vinylogous C5-curcuminoid derivatives were the only cinnamoyl derivatives that gave a thia-Michael reaction. From a mechanistic standpoint, loss of conjugation in the adduct might underlie the lack of a native Michael reactivity. This property is restored by the presence of another conjugating group on the carbonyl, as in chalcones and C5-curcuminoids. A critical mechanistic revision of the chemical and biomedical literature on cinnamaldehyde and related compounds seems therefore required.

Synthesis and Structure of Low-valent η4 -Cinnamaldehyde Cobalt Complexes

Three η4-(C=C–C=O) coordination cobalt(I) complexes 1–3 were synthesized by the reactions of cinnamaldehyde, p-fluorocinnamaldehyde, and p-chlorocinnamaldehyde with CoMe(PMe3)4. Complex 4 as η2-(C=C) coordination was prepared by the reaction of chalcone with Co(PMe3)4. The structures of complexes 1–4 were confirmed by single-crystal X-ray diffraction. Although the reactions didn't undergo C–H bond activation and decarbonylation, the formation of complexes 1–4 deepens our understanding of the reactions between α,β-unsaturated aldehyde or ketone with low-valent central cobalt atom.

Intermediates and products in the reaction of cinnamaldehyde with (HOCH2)3P in methanol

GRAPHICAL ABSTRACT

Nucleophilicity Parameters of Stabilized Iodonium Ylides for Characterizing Their Synthetic Potential.

Kinetics and mechanisms of the reactions of the β-dicarbonyl-substituted iodonium ylides 1(a-d) with several π-conjugated carbenium and iminium ions have been investigated. All reactions proceed with rate-determining attack of the electrophile at the nucleophilic carbon center of the ylides to give iodonium ions, which rapidly expel iodobenzene and undergo different subsequent reactions. The second-order rate constants k2 for the reactions of the iodonium ylides with benzhydrylium ions correlate linearly with the electrophilicity parameters E of the benzhydrylium ions and thus follow the linear free energy relationship log k(20 °C) = sN(N + E) (eq 1), where electrophiles are characterized by one parameter (E), while nucleophiles are characterized by two parameters: the nucleophilicity N and the susceptibility sN. The nucleophilicity parameters 4 < N < 8 for iodonium ylides 1(a-d) derived from these correlations show that substituting hydrogen for Ph-I(+) at the carbanionic center of Meldrum's acid or dimedone, respectively, reduces the nucleophilicity by approximately 10 orders of magnitude. The iodonium ylides 1(a-d) thus have nucleophilicities similar to those of pyrroles, indoles, and silylated enol ethers and, therefore, should be suitable substrates in iminium-activated reactions. Good agreement of the measured rate constant for the cyclopropanation of the imidazolidinone-derived iminium ion 10a with the iodonium ylide 1a with the rate constant calculated by eq 1 suggests a stepwise mechanism in which the initial nucleophilic attack of the iodonium ylide at the iminium ion is rate-determining. The reaction of cinnamaldehyde with iodonium ylide 1a catalyzed by (5S)-5-benzyl-2,2,3-trimethyl-imidazolidin-4-one (11a, MacMillan's first-generation catalyst) gives the corresponding cyclopropane with an enantiomeric ratio of 70/30 and, thus, provides proof of principle that iodonium ylides are suitable substrates for iminium-activated cyclopropanations.

ChemInform Abstract: Enantio‐ and Diastereoselective Cross‐Annulation of Enal and Ketone with New Chiral Bicyclic N‐Heterocyclic Carbene Catalysts.

AbstractA series of 17 new chiral bicyclic imidazolium salts are tested as catalysts for the enantio‐ and diastereoselective cross‐annulation reaction of cinnamaldehyde (I) and trifluoroacetophenone (II).

Investigating the mechanism of the selective hydrogenation reaction of cinnamaldehyde catalyzed by Ptn clusters.

Cinnamaldehyde (CAL) belongs to the group of aromatic α,β-unsaturated aldehydes; the selective hydrogenation of CAL plays an important role in the fine chemical and pharmaceutical industries. Using Ptn clusters as catalytic models, we studied the selective hydrogenation reaction mechanism for CAL catalyzed by Ptn (n = 6, 10, 14, 18) clusters by means of B3LYP in density functional theory at the 6-31+ G(d) level (the LanL2DZ extra basis set was used for the Pt atom). The rationality of the transition state was proved by vibration frequency analysis and intrinsic reaction coordinate computation. Moreover, atoms in molecules theory and nature bond orbital theory were applied to discuss the interaction among orbitals and the bonding characteristics. The results indicate that three kinds of products, namely 3-phenylpropyl aldehyde, 3-phenyl allyl alcohol and cinnamyl alcohol, are produced in the selective hydrogenation reaction catalyzed by Ptn clusters; each pathway possesses two reaction channels. Ptn clusters are more likely to catalyze the activation and hydrogenation of the C = O bond in CAL molecules, eventually producing cinnamic alcohol, which proves that Ptn clusters have a strong reaction selectivity to catalyze CAL. The reaction selectivity of the catalyzer cluster is closely related to the size of the Ptn cluster, with Pt14 clusters having the greatest reaction selectivity. Graphical Abstract The reaction mechanism for the selective hydrogenation reaction ofcinnamaldehyde catalyzed by Ptn clusters was studied by densityfunctional theory. The reactionselectivity of cluster catalyzer was concluded to be closely related to the size of Ptn clusters, with Pt14 clusters having the greatest reaction selectivity.

ChemInform Abstract: Two Reaction Mechanisms via Iminium Ion Intermediates: The Different Reactivities of Diphenylprolinol Silyl Ether and Trifluoromethyl‐Substituted Diarylprolinol Silyl Ether.

AbstractThe reaction of cinnamaldehyde with cyclopentadiene in the presence of DPPL as catalyst leads to substituted cyclopentadiene Michael‐type adducts (III) and (IV), whilst the reaction with DTFP catalyst affords Diels—Alder adducts (V) and (VI).

Synthesis, characterization and crystal structures of new organic compounds containing cyanoacrylic acid

New organic compounds, cin-aa (1) and mecin-aa (2), containing cyanoacrylic acid as an acceptor were synthesized by the reaction of cinnamaldehyde or α-methylcinnamaldehyde with cyanoaceticacid in acetonitrile. The compounds 1 and 2 were characterized by elemental analyses (CHN), FT-IR, UV–Vis and 1H NMR spectroscopy, and their monoclinic centrosymmetric structures were determined by single crystal X-ray diffraction. In addition, they were tested for their potential use as photosensitizers in dye-sensitized solar cells (DSSC). Overall conversion efficiencies of 1 and 2 were determined as 0.04 and 0.09, respectively, under full sunlight irradiation. To get further insight into the molecular structure of 1 and 2, their geometry and energies of HOMO and LUMO were optimized by density functional theory calculation at the B3LYP/6-31G(d) level with Gaussian 03.

Synthesis and crystal structure of {Ru2(CO)6-μ2-η3-[(Ph)CC(H)C(H)NC(H)C(H)C(H)(Ph)]} — The first structurally characterized iminoallyl ruthenium carbonyl complex

The dinuclear ruthenium carbonyl cluster {Ru 2 (CO) 6 -μ 2 -η 3 -[(Ph)C C(H) C(H) N C(H) C(H) C(H)(Ph)]} is produced from the reaction of cinnamaldehyde and Ru 3 (CO) 12 in a 2.0 M solution of ammonia in ethanol. From the crystal structure it gets obvious that ammonia reacted with two molecules of cinnamaldehyde. The resulting ligand may best be described as a formally dianionic ruthenium coordinated imino-allyl-system with one exocyclic 3-phenylallylidene unit that shows no interaction with the transition metals whereas the second one is bound to ruthenium via a C H activation step in γ-position with respect to the nitrogen atom.

Reaction of cinnamaldehyde and derivatives with Raney Ni–Al alloy and Al powder in water. Reduction or oxido-reduction?

A series of experiments dealing with the reduction of cinnamaldehyde and parent compounds was carried out in completely aqueous media in order to assess the character of this process. We wish to show that the treatment of these substrates in water with Raney catalysts is an oxido-reductive process.

ChemInform Abstract: Radical Reduction of Passerini 3CR Adducts by SmI2/HMPA.

Abstractβ,γ‐Unsaturated amides are synthesized from crude Passerini 3CR adducts, generated by reaction of cinnamaldehydes, isocyanides and acetic acid, via radical reduction.

Solvent-free reductive amination of aromatic aldehydes catalyzed by CeCl3·7H2O

CeCl3·7H2O is found to be an efficient catalyst in the one-pot reductive amination of aromatic aldehydes under solvent-free conditions. Selectivity is observed in the reaction of cinnamaldehyde with aromatic amines, providing an alternative green route to the synthesis of N-cinnamyl anilines. The reaction conditions are mild and the desired product is obtained in good yields.

Reversible decomposition of mono(α-hydroxy)phosphines and their reaction with α,β-unsaturated aldehydes

The mono(α-hydroxy)phosphines R2PCH(OH)R′ (R = Ph, R′ = H, Et, CH2Ph, Ph, p-X-C6H4; R = cyclohexyl, R′ = Ph) are prepared under solvent-free conditions by a 1:1 reaction of Ph2PH with the appropriate aldehyde, and their stabilities (with respect to reversible dissociation into reactants), studied in DMSO, Et2O, and MeOH, increase with decreased basicity of the hydroxyphosphine; for example, for the Ph2PCH(OH)C6H4-p-X phosphines, stability decreases in the order: X = CN &gt; Cl &gt; F &gt; H &gt; Me &gt; OMe. A 1:1 room-temperature reaction of the (α-hydroxy)phosphines (except for R′ = H) with cinnamaldehyde in DMSO slowly yields the known mono- and di-phosphines Ph2PCH(Ph)CH2CHO (4a) and Ph2PCH(Ph)CH2CH(PPh2)OH (10a), and the corresponding R′CHO aldehyde. In MeOH, the sequentially formed intermediates, PhCH=CHCH(OH)PPh2, PhCH(OH)CH=CHPPh2, and Ph2PCH(Ph)CH=CHOH, were detected en route to 4a and 10a. Reaction of cinnamaldehyde with Ph2PCH2OH gives 4a and the hemiacetal Ph2PCH2OCH2OH formed from the reactant hydroxyphosphine with the co-product formaldehyde. Reactions carried out in MeOH are faster because of the formation of hemiacetals from the phosphine-containing aldehyde products; thus, 4a is seen as Ph2PCH(Ph)CH2CH(OMe)(OH), which on dissolution in Et2O, reverts to the aldehyde. The reaction rates and equilibrium concentrations of the various species depend on the R′ group of the reactant phosphine; the rates of consumption of the hydroxyphosphines in the reactions with cinnamaldehyde decrease in the order: Ph2PCH(OH)Ph &gt; Ph2PCH(OH)Et &gt; Ph2PCH(OH)CH2Ph &gt;&gt; Ph2PCH2OH. The reactivity pattern of Ph2PCH(OH)Ph with sinapaldehyde [3,5-(OMe)2-4-OH-cinnamaldehyde] in DMSO follows that seen for cinnamaldehyde. Reaction of Ph2PH with cinnamaldehyde in DMSO affords 4a and 10a via the same intermediates seen with the Ph2PCH(OH)R′ reagents, but these latter reactions are thought to occur via direct attack on cinnamaldehyde by the hydroxyphosphine rather than via Ph2PH.

Structure of Polymeric Polyphenols of Cinnamon Bark Deduced from Condensation Products of Cinnamaldehyde with Catechin and Procyanidins

Structures of two condensation products obtained by the reaction of cinnamaldehyde with (+)-catechin were determined by spectroscopic methods. One had two phenylpropanoid units at the C-6 and C-8 positions of the catechin skeleton. The other product had a dimeric structure with two catechin and two phenylpropanoid units. Matrix-assisted laser desorption time-of-flight mass spectrometric analysis of the reaction products of cinnamaldehyde with procyanidin B1 suggested that procyanidins were oligomerized in a manner similar to the reaction with catechin. Furthermore, (13)C NMR spectral comparison of the condensation products with the polymeric procyanidins obtained from commercial cinnamon bark strongly suggested that the procyanidins in the cinnamon bark also were polymerized by reaction with cinnamaldehyde.

Tris(2,4,6-Trimethoxyphenyl)phosphine: Base Catalyst in the Transformation of α,β-Unsaturated Aldehydes to Saturated Carboxylic-Acid Derivatives

We have focused on the basicity of Tris(2,4,6-trimethoxyphenyl)phosphine (TTMPP) in organic synthesis. To extend the utility of TTMPP, we examined the reaction of α,β-unsaturated aldehydes with trimethylsilyl cyanide in the presence of TTMPP. Furthermore, to clarify the basic character of TTMPP, we measured 31P NMR of TTMPP and related compounds. First, the reaction of cinnamaldehydes with trimethylsilyl cyanide in the presence of a catalytic amount of TTMPP afforded the corresponding saturated carboxylic acids after hydrolysis with 1M HCl. Treatment of the reaction mixture with alcohols or amines instead of 1M HCl gave the corresponding saturated esters and amides, respectively. As a result of studies of the reaction mechanism, it was revealed that the reaction proceeded via silylcyanation of α,β-unsaturated aldehydes with trimethylsilyl cyanide to produce trimethylsilyl ethers of cyanohydrin and subsequent isomerization that formed α-trimethylsiloxy vinyl cyanides, which were hydrolyzed to give saturated carboxylic acids.

Kinetic Analysis of Hydrogenation of Cinnamaldehyde with a Ruthenium Complex Catalyst in Several Solvents.

Hydrogenation of cinnamaldehyde (CAL) with a ruthenium-triphenylphosphine complex was carried out under various conditions in several solvents such as N, N-dimethylformamide (DMF), 1-methyl-2-pyrrolidone (NMP) and ethyl acetate (AcEt). In this reaction, cinnamyl alcohol (COL), hydrocinnamaldehyde (HCAL) and hydrocinnamyl alcohol (HCOL) are formed. Among the solvents used, DMF gives the highest reaction rate and the highest selectivity for COL. The reaction order of the substrate consumption also changes with the solvent. The rate of CAL consumption is of the first order with respect to its concentration in DMF, while those in the other solvents are of the zeroth order. Hydrogenation of COL to HCOL was found to be negligible under the present reaction conditions. By simulation for the concentration–time profiles of the substrate and the products obtained in DMF, rate constants for the elemental reactions involved in the title reaction, i.e. the hydrogenation reactions of CAL to COL, of CAL to HCAL and of HCAL to HCOL, were determined. These rate constants increase linearly with H2 pressure below 4 MPa. Above this pressure, they remain practically constant. Effect of the ligand/metal ratio on these rate constants was also investigated.

Interaction of cinnamaldehyde (a sensitizer in fragrance) with protein.

Formation of a cinnamaldehyde-protein conjugate in the skin by reaction of cinnamaldehyde with nucleophilic groups in proteins is considered to be responsible for the observed immunogenicity. The kinetics of the reaction of bovine serum albumin with cinnamaldehyde in aqueous solution at 30 degrees C have been investigated, and the rate of formation of conjugate over the pH range 6.4-10.5 showed a first-order dependence on cinnamaldehyde concentration. The cinnamaldehyde binding sites on the protein appeared mostly or exclusively to be the thiol groups of cysteine residues.