Parallel consecutive reactions in a fluidized catalyst bed

1984 ◽  
Vol 28 (2) ◽  
pp. 79-86 ◽  
Author(s):  
M. Perrier ◽  
W. Bauer ◽  
W.Ian Patterson ◽  
C. Chavarie ◽  
D. Jutras
Keyword(s):  
Consecutive Reactions ◽  
Fluidized Catalyst Bed

Possible application of approximate models for calculation of selectivity of consecutive reactions under the effect of mass transfer

1982 ◽  
Vol 47 (5) ◽  
pp. 1301-1309 ◽  
Author(s):  
František Kaštánek ◽  
Marie Fialová
Keyword(s):  
Mass Transfer ◽  
Numerical Method ◽  
Analytical Method ◽  
Approximate Analytical Method ◽  
Approximate Models ◽  
Consecutive Reactions ◽  
The Difference

The possibility of use of approximate models for calculation of selectivity of consecutive reactions is critically analysed. Simple empirical criteria are proposed which enable safer application of approximate analytical reactions. A more universal modification has been formulated by use of which the difference of selectivity calculated by the exact numerical method and by the approximate analytical method is at maximum 12%.

Kinetics of the reaction between hexamethylenediisocyanate and 1-pentanol

1983 ◽  
Vol 48 (11) ◽  
pp. 3279-3286
Author(s):  
Slavko Hudeček ◽  
Miloslav Bohdanecký ◽  
Ivana Hudečková ◽  
Pavel Špaček ◽  
Pavel Čefelín
Keyword(s):  
Liquid Chromatography ◽  
Rate Constants ◽  
Reversed Phase ◽  
Order Reaction ◽  
Second Order ◽  
Second Order Reaction ◽  
Reversed Phase Liquid Chromatography ◽  
Consecutive Reactions ◽  
Phase Liquid ◽  
Kinetics Of

The reaction between hexamethylenediisocyanate and 1-pentanol in toluene was studied by means of reversed-phase liquid chromatography. By employing this method, it was possible to determine all components of the reaction mixture including both products, i.e. N-(6-isocyanate hexyl)pentylcarbamate and N,N'-bis(pentyloxycarbonyl)hexamethylenediamine. Relations for the calculation of kinetic constants were derived assuming a competitive consecutive second-order reaction. It was demonstrated that the reaction involved in this case is indeed a second-order reaction, and the rate constants of the first and second consecutive reactions were determined.

Cw CO2 laser driven oxidation of some perhalogenocycloalkenes

1991 ◽  
Vol 56 (2) ◽  
pp. 398-405 ◽  
Author(s):  
Josef Pola ◽  
Jaroslav Včelák ◽  
Zdeněk Chvátal
Keyword(s):  
Co2 Laser ◽  
Total Pressure ◽  
Diels Alder ◽  
Title Reaction ◽  
Consecutive Reactions ◽  
Cw Co2 Laser

The title reaction of hexafluorocyclobutene, 1,2-dichloro-3,3,4,4-tetrafluorocyclobutene and decafluorocyclohexene studied at total pressure 13.3 and 16 kPa yield oxalyl halides COX.COX (X = F, Cl) and C2F4 that undergo consecutive reactions to COF2, CO and X2. The oxidation of decafluorocyclohexene is preceded by retro-Diels-Alder decomposition affording hexafluorocyclobutene and C2F4. Two alternative mechanisms for the oxidation of the cyclobutenes are presented, one involving a novel cleavage of intermediary bicyclic dioxetanes. The decomposition of oxalyl fluoride into COF2 and CO is favored over its oxidation.

scholarly journals One-Pot Synthesis of Novel Multisubstituted 1-Alkoxyindoles

Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1466
Author(s):  
Ye Eun Kim ◽  
Hyunsung Cho ◽  
Yoo Jin Lim ◽  
Chorong Kim ◽  
Sang Hyup Lee
Keyword(s):  
Alkyl Halide ◽  
The Novel ◽  
Reaction Conditions ◽  
One Pot ◽  
One Pot Synthesis ◽  
Consecutive Reactions ◽  
Intramolecular Condensation ◽  
Synthetic Sequence ◽  
Novel Target

Studies on a one-pot synthesis of novel multisubstituted 1-alkoxyindoles 1 and their mechanistic investigations are presented. The synthesis of 1 was successfully achieved through consecutive four step reactions from substrates 2. The substrates 2, prepared through a two-step synthetic sequence, underwent three consecutive reactions of nitro reduction, intramolecular condensation, and nucleophilic 1,5-addition to provide the intermediates, 1-hydroxyindoles 8, which then were alkylated in situ with alkyl halide to afford the novel target products 1. We optimized the reaction conditions for 1 focusing on the alkylation step, along with the consideration of formation of intermediates 8. The optimized condition was SnCl2·2H2O (3.3 eq) and alcohols (R1OH, 2.0 eq) for 1–2 h at 40 °C and then, base (10 eq) and alkyl halides (R2Y, 2.0 eq) for 1–4 h at 25–50 °C. Notably, all four step reactions were performed in one-pot to give 1 in good to modest yields. Furthermore, the mechanistic aspects were also discussed regarding the reaction pathways and the formation of side products. The significance lies in development of efficient one-pot reactions and in generation of new 1-alkoxyindoles.

scholarly journals Methylofuran is a prosthetic group of the formyltransferase/hydrolase complex and shuttles one-carbon units between two active sites

2019 ◽  
Vol 116 (51) ◽  
pp. 25583-25590 ◽  
Author(s):  
Jethro L. Hemmann ◽  
Tristan Wagner ◽  
Seigo Shima ◽  
Julia A. Vorholt
Keyword(s):  
Active Sites ◽  
Bacterial Species ◽  
Methanogenic Archaea ◽  
Side Chain ◽  
Strong Interactions ◽  
Prosthetic Group ◽  
Additional Function ◽  
Amide Bonds ◽  
Consecutive Reactions ◽  
The One

Methylotrophy, the ability of microorganisms to grow on reduced one-carbon substrates such as methane or methanol, is a feature of various bacterial species. The prevailing oxidation pathway depends on tetrahydromethanopterin (H4MPT) and methylofuran (MYFR), an analog of methanofuran from methanogenic archaea. Formyltransferase/hydrolase complex (Fhc) generates formate from formyl-H4MPT in two consecutive reactions where MYFR acts as a carrier of one-carbon units. Recently, we chemically characterized MYFR from the model methylotrophMethylorubrum extorquensand identified an unusually long polyglutamate side chain of up to 24 glutamates. Here, we report on the crystal structure of Fhc to investigate the function of the polyglutamate side chain in MYFR and the relatedness of the enzyme complex with the orthologous enzymes in archaea. We identified MYFR as a prosthetic group that is tightly, but noncovalently, bound to Fhc. Surprisingly, the structure of Fhc together with MYFR revealed that the polyglutamate side chain of MYFR is branched and contains glutamates with amide bonds at both their α- and γ-carboxyl groups. This negatively charged and branched polyglutamate side chain interacts with a cluster of conserved positively charged residues of Fhc, allowing for strong interactions. The MYFR binding site is located equidistantly from the active site of the formyltransferase (FhcD) and metallo-hydrolase (FhcA). The polyglutamate serves therefore an additional function as a swinging linker to shuttle the one-carbon carrying amine between the two active sites, thereby likely increasing overall catalysis while decreasing the need for high intracellular MYFR concentrations.

ChemInform Abstract: Diagnosing Consecutive Reactions of Hypochlorite: pH and Oxidative Decarboxylation/Halogenation.

ChemInform ◽  
1987 ◽  
Vol 18 (5) ◽  
Author(s):  
B. J. GILLIOTTE ◽  
C. L. SANDERS ◽  
L. K. WALL ◽  
R. G. LANDOLT
Keyword(s):  
Oxidative Decarboxylation ◽  
Consecutive Reactions

Consecutive reactions in the thermal decomposition of phenylalkyldiazirines

1977 ◽  
Vol 55 (20) ◽  
pp. 3596-3601 ◽  
Author(s):  
Michael T. H. Liu ◽  
Barry M. Jennings
Keyword(s):  
Thermal Decomposition ◽  
Kinetic Parameters ◽  
Diazo Compounds ◽  
First Order ◽  
Temperature Range ◽  
Decomposition Reactions ◽  
Consecutive Reactions ◽  
Rate Processes ◽  
Subsequent Decomposition

The thermal decomposition of phenyl-n-butyldiazirine and of phenylmethyldiazirine in DMSO and in HOAc have been investigated over the temperature range 80–130 °C. The intermediate diazo compounds, 1-phenyl-1-diazopentane and 1-phenyldiazoethane respectively have been detected and isolated. The decomposition of phenyl-n-butyldiazirine and the subsequent decomposition of its product, 1-phenyl-1-diazopentane, are an illustration of consecutive reactions. The kinetic parameters for the isomerization and decomposition reactions have been determined. The isomerization of phenylmethyldiazirine to 1-phenyldiazoethane is first order and probably unimolecular but the kinetics for the subsequent reactions of 1-phenyldiazoethane are complicated by several competing rate processes.

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