Reduction Of Cinnamaldehyde Research Articles

Comparison of Catalytic Properties of the Easily Interconvertible, Water-Soluble [RuHCl(CO)(mtppms-Na)3] and [RuH(H2O)(CO)(mtppms-Na)3][BF4

The effect of the mobile interconversion of [RuHCl(CO)(mtppms-Na)3] 1, and [RuH(H2O)(CO)(mtppms-Na)3]+ 2, was studied in hydrogenation of phenylacetylene and cinnamaldehyde in aqueous–organic biphasic systems, as a function of the chloride concentration and the pH of the aqueous phase. Catalytic activity of the two complexes was also determined in homogeneous organic solvents without any additives. In the biphasic system, the rate of selective hydrogenation of phenylacetylene to styrene was strongly increased upon addition of NaCl, while the reaction of cinnamaldehyde slowed, with no change in product distribution. Both reactions responded with a rate decrease upon increasing the pH of the aqueous phase. It was concluded that hydrogenation of phenylacetylene was catalyzed by 1 with no chloride dissociation, while in the reduction of cinnamaldehyde, the aquo-complex 2 was the active catalytic species. Catalytic cycles were suggested to rationalize these findings.

TiO2/(1-butyl-3-methylimidazolium hexafluorophosphate) Based Sensor: A Strategy for the Detection of Cinnamaldehyde

An ultrasensitive voltammetric sensor has been developed for selective determination of cinnamaldehyde (CNN) based upon electrocatalytic properties of titanium oxide and (1-butyl-3-methylimidazolium hexafluorophosphate). The fabricated sensor was characterized by transmission electron microscopy (TEM) and electron impedance spectroscopy (EIS). The electrochemical behavior of cinnamaldehyde at the modified sensor was studied using square wave voltammetry as a function of concentration of cinnamaldehyde. This titanium oxide and ionic liquid based sensor displayed excellent electrocatalytic activity toward reduction of cinnamaldehyde. Under optimized experimental conditions, the reduction peak current was linear over the concentration range from 0.02 μM to 0.14 μM, with limit of detection (LOD) and limit of quantification of 2.6 nM and 8.0 nM respectively. The fabricated sensor was also successfully employed for the analysis of cinnamaldehyde in real samples.

Insight into the Meerwein-Ponndorf-Verley reduction of cinnamaldehyde over MgAl oxides catalysts

The Meerwein-Ponndorf-Verley (MPV) reduction of cinnamaldehyde with 2-propanol to cinnamyl alcohol over MgAl oxide catalysts originated from hydrotalcites was systematically studied. By investigating the influence of calcination temperature and Mg/Al molar ratio on alkaline density and catalytic performance, the relationship between alkaline density and catalytic performance had been established. It was well confirmed that there was an optimal W/M alkaline density ratio for cinnamaldehyde reduction, which lay in the synergetic effect of weak base sites and moderate base sites. In addition, the reaction parameters, reaction pathway, and stability of catalyst were also investigated. Interestingly, the formation of 5-methyl-3-phenylcyclopent-2-en-1-one (1-ONE) was observed for the first time by condensation of cinnamaldehyde and 2-propanol, which was promoted by increasing total alkaline density. And 1-cinnamyl 2-propyl ether (CPE) was detected just under high starting cinnamaldehyde concentration. In the recycling, the used MgAl oxide catalyst exhibited poor activity due to the strong adsorption of organic molecular on active sites, while its reactivity was recovered by calcining simply.

A better model for the mechanism of Lithal (LAH) reduction of cinnamaldehyde?

A better model for the mechanism of Lithal (LAH) reduction of cinnamaldehyde?

Synthesis of Cinnamyl Alcohol from Cinnamaldehyde with Bacillus stearothermophilus Alcohol Dehydrogenase as the Isolated Enzyme and in Recombinant E. coli Cells

The synthesis of the aroma chemical cinnamyl alcohol (CMO) by means of enzymatic reduction of cinnamaldehyde (CMA) was investigated using NADH-dependent alcohol dehydrogenase from Bacillus stearothermophilus both as an isolated enzyme, and in recombinant Escherichia coli whole cells. The influence of parameters such as reaction time and cofactor, substrate, co-substrate 2-propanol and biocatalyst concentrations on the bioreduction reaction was investigated and an efficient and sustainable one-phase system developed. The reduction of CMA (0.5 g/L, 3.8 mmol/L) by the isolated enzyme occurred in 3 h at 50 °C with 97% conversion, and yielded high purity CMO (≥98%) with a yield of 88% and a productivity of 50 g/genzyme. The reduction of 12.5 g/L (94 mmol/L) CMA by whole cells in 6 h, at 37 °C and no requirement of external cofactor occurred with 97% conversion, 82% yield of 98% pure alcohol and a productivity of 34 mg/gwet cell weight. The results demonstrate the microbial system as a practical and efficient method for larger-scale synthesis of CMO.

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.

Studies on high chemical reactivity of nano-NaH

A comparison between the initial reaction rates of nanometric and commercial NaH has been studied in four test reactions: 1) hydrogenolysis of chlorobenzene; 2) selective reduction of cinnamaldehyde to cinnamyl alcohol; 3) metallation of dimethyl sulfoxide; and 4) catalytic hydrogenation of olefins. The experimental results indicate that when NaH is used as a chemical reagent in the first three reactions, the initial reaction rates of nano-NaH is 230, 120 and 110 times higher than those of the commercial ones respectively, and it is in agreement with the difference in specific surface areas between these two forms of NaH. When NaH is used as a catalyst component together with Cp2TiCl2 in the fourth reaction, catalyst with nano-NaH gives extremely high activity in the hydrogenation of olefins, while the one with commercial NaH gives no activity at all even if a large amount of the commercial NaH is used to make the total surface area equivalent to that of nano-NaH. Thus, it is evident that although large specific surface area is important for nano-NaH to be used as a catalyst component, high surface energy with surface defects seems to be more important. The large specific surface and the activated surface of nano-NaH with high surface energy should be the main factors for their extremely high chemical reactivity, while whether the former or the latter one plays a leading role depends on the type of reactions involved.

Reduction of Carbonyl Compounds to the Corresponding Alcohols with Isopropanol on Dehydrated Alumina under Microwave Irradiation.

AbstractFor Abstract see ChemInform Abstract in Full Text.

REDUCTION OF CARBONYL COMPOUNDS TO THE CORRESPONDING ALCOHOLS WITH ISOPROPANOL ON DEHYDRATED ALUMINA UNDER MICROWAVE IRRADIATION

ABSTRACT The reduction of different types of aldehydes and ketones were performed in the presence of isopropylalcohol (as solvent and hydride source) under microwave irradiation. It is proved that dehydrated Woelm chromatographic alumina supported KOH catalyses these transformations. Regioselectivity was observed in the reduction of cinnamaldehyde and chemoselectivity was observed in the reduction of carbonyl in the presence of nitro group.

Kinetics of reduction of cinnamaldehyde by means of hydrido- and deuteridocobalt tetracarbonyl

The reaction of HCo(CO)4 (HT) or DCo(CO)4 (DT) with excess cinnamaldehyde (CA) in methylcyclohexane (RH) at 22.2° and under 1 atm of CO follows pseudo-first-order kinetics in HT or DT with an inverse isotopic effect of 0.54. Identified products of the reaction are hydrocinnamaldehyde (HCA) and styrene (STY). The STY is believed to be an artifact of the thermal decomposition of the true product PhCH2CH2C( (DOUBLE BOND) O)Co(CO)4 (X) or its isomer. Reduction of the carbon-carbon double bond in CA is effected by hydrogen from both the cobalt compound and RH. It is proposed that the reaction involves a free-radical chain mechanism in which the rate of the slow step is proportional to [CA], the initial molar concentration of CA raised to a power of 1.5− 1.8. Additionally the rate of conversion of CA to HCA and X meets the criteria of a homocompetitive reaction with [CA], [HCA], and [STY] simple functions of t0.5 (where t is reaction time) for use of DT or (in a single case) a function of (t0.5 + t) for use of HT. © 1997 John Wiley & Sons, Inc. Int J Chem Kinet 29: 473–481, 1997.

Reduction of cinnamaldehyde and unsaturated acids byBotrytis cinerea

The bio-transformation of cinnamaldehyde (1), (E)-3-hexenoic acid (5) and (E)-3-octenoic acid (10) was studied with four strains ofBotrytis cinerea in two different media. In all cases, predominant microbial reduction of (1), (5) and (10) was observed leading to (E)-cinnamic alcohol (2) and dihydrocinnamic alcohol (4) as well as (E)-3-hexen-l-ol (6) and (E)-3-octen-l-ol (11) respectively. Moreover, minor amounts of the by-products (Z)-cinnamic alcohol (3), (E)-2-(7), (Z)-3- (8) and (Z)-2-hexen-l-ol (9) as well as (E)-2-(12) and (Z)-3-octen-l-ol (13) and 1-octen-3-ol (14) were found. The bio-conversion products were identified by capillary gas chromatography (HRGC) and coupled capillary gas chromatography-mass spectrometry (HRGC-MS) after extraction and sample preparation.

Stereochemical course of the reduction of cinnamaldehyde and cinnamyl alcohol to 3-phenylpropanol by fermenting Baker's yeast

Reduction of cinnamyl alcohol by fermenting baker's yeast proceeds with formal trans addition of hydrogen across the double bond, a pro-R hydrogen atom being introduced at position 2; (1S)-3-phenyl[1-2H1]pro- panol is obtained from [formyl-2H]cinnamaldehyde and from [1-2H2]cinnamyl alcohol under the same conditions.

Polarographic Studies in Acetonitrile and Dimethylformamide: IX . Behavior of α,β‐Unsaturated Carbonyl Compounds

Benzalacetophenone, benzalacetone, cinnamaldehyde, and crotonaldehyde were reduced stepwise at the dropping mercury electrode in anhydrous dimethylformamide. Large‐scale electrolytic reductions were performed on the compounds in the presence and absence of carbon dioxide. Carbonation of the dianions of benzalacetophenone and benzalacetone gave α‐phenyl‐β‐benzoyl propionic acid and α‐phenyllevulinic acid, respectively. In the absence of carbon dioxide, the dianion of benzalacetophenone gave a polymer. The anion‐free radical of benzalacetophenone in the presence of carbon dioxide gave a monomeric dicarboxylic acid and a dimeric monocarboxylic acid. In the absence of carbon dioxide a trimer was obtained. The reduction of cinnamaldehyde and crotonaldehyde gave tars.