Butyryl Chloride Research Articles

Synthesis and Bioactivity of Xyridin A and B, Metabolites from Xyris indica.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Liquid chromatographic determination of bisphenols based on intramolecular excimer-forming fluorescence derivatization

A highly selective and sensitive fluorometric method for the determination of bisphenols has been developed. This method is based on an intramolecular excimer-forming fluorescence derivatization with a pyrene reagent, 4-(1-pyrene)butyryl chloride (PBC), followed by reversed-phase liquid chromatography (LC). The bisphenols, containing two phenolic hydroxyl groups in a molecule, were converted to the corresponding dipyrene-labeled derivatives by reaction with PBC. The derivatives afforded intramolecular excimer fluorescence (440–520 nm) which can clearly be discriminated from normal fluorescence (360–420 nm) emitted from PBC and monopyrene-labeled derivatives of monophenols. The PBC derivatives of bisphenols could be separated by reversed-phase LC on an octyl column with isocratic elution. The detection limits (signal-to-noise ratio = 3) for bisphenols were 3.0–5.0 fmol, for a 20 μl injection. The method was successfully applied to the determination of bisphenol A in hot water in contact with commercially available baby bottle samples after solid-phase extraction.

Synthesis and bioactivity of xyridin A and B, metabolites from xyris indica

AbstractA facile synthesis of the title isocoumarins isolated from. Xyris indica was accomplished. Condensation of butanoyl chloride and 2‐oxo‐butanoyl chloride with 3,4‐methylenedioxyhomophthalic acid afforded xyridin A and xyridin B respectively. Xyridin A was saponified to the corresponding keto acid which on reduction furnished the (±)‐3,4‐dihydro‐6,7‐methylenedioxy‐3‐propylisocoumarin. All of the synthesized compounds were examined in vitro for antibacterial and antifungal activities.

Application of solid–liquid phase transfer catalysis system for peroxyester synthesis: A kinetic study of hydroperoxides acylation in the presence of solid sodium carbonate

In the research described below, we have developed a convenient and effective method of synthesis of organic peroxyesters to achieve 60–98% yields under extreme mild conditions. The study has been conducted on a model system using a reaction of acylation of 1-methyl-1-phenylethyl hydroperoxide (CHP) by means of butyryl chloride in the presence of solid Na2CO3 and being performed under conditions of phase transfer catalysis (PTC). The effect of the following parameters on the reaction was tested: temperature, Na2CO3 amount, catalyst structure and solvent polarity.

Acylation of aromatic compounds using moisture insensitive InCl 3 impregnated mesoporous Si-MCM-41 catalyst

Acylation of aromatic compounds (benzene, toluene, p-xylene, mesitylene, anisole, naphthalene, methylnaphthalene and methoxynaphthalene) by an acyl chloride (benzoyl chloride, phenylacetyl chloride, propionyl chloride or butyryl chloride) in high yield, in a short reaction period (3 h), even in the presence of moisture in the aromatic substrate or solvent (dichloroethane), can be accomplished at low temperature (80±1°C) using an InCl 3 impregnated Si-MCM-41 catalyst in low catalyst concentration.

Application of ketenes to well-defined polyester synthesis. III. Living anionic polymerization of ethyl(4-methoxyphenyl)ketene?Development of polyester having masked phenol side chain

A novel ketene, ethyl(4-methoxyphenyl)ketene (EMPK), was synthesized by the dehydrochlorination of 2-(4-methoxyphenyl)butanoyl chloride. The anionic polymerizations of EMPK by butyllithium in tetrahydrofuran at −20 °C were carried out with a varying feed ratio to give the corresponding polyesters having predictable molecular weights and narrow molecular weight distributions, quantitatively. The selective formation of the polyester was confirmed by IR analysis, and the reductive degradation of the polymer was supported by lithium–aluminium hydride. The second feed of the monomer (after the first stage of polymerization) resulted in the formation of the polymer with the expectedly increased molecular weight and low polydispersity to strongly support the living mechanism of this polymerization. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1596–1600, 2001

Effect of Blending of Cholesteric Cellulose Esters on the Pitch Height

Butyric esters (BuPC) of hydroxypropylcellulose (HPC) with different degrees of substitution (DS) were obtained by the reaction of (2-hydroxypropyl)cellulose with butyryl chloride. Blends of these BuPCs were obtained from ternary solutions by removal of the com mon solvent. The blends displayed thermotropic choles teric mesophases and showed iridescent colors at ambient temperatures depending on the blend composition. The spectroscopic analysis of the blends showed systematic variations of the reflection colors with variations of the ratio of the blend components between the reflection colors of the pure blend components covering the range from 453-938 nm corresponding to pitch heights from 308 640 nm.

Acylation of Benzene over Clay and Mesoporous Si-MCM-41 Supported InCl3, GaCl3 and ZnCl2 Catalysts

Liquid phase acylation of benzene by acyl chloride (e.g., benzoyl chloride, butyryl chloride or phenyl acetyl chloride) over InCl3, GaCl3 and ZnCl2 supported on commercial clays (viz. montmorillonite-K10, montmorillonite-KSF and kaolin) or high silica mesoporous MCM-41 at 80°C has been investigated. The Mont.-K10 and Si-MCM-41 supported InCl3 and GaCl3 catalysts showed high activity in the acyation of benzene by benzoyl chloride even in the presence of moisture in the reaction mixture. The redox function of the supported InCl3, GaCl3 or ZnCl2 catalysts seems to play a very important role in the acylation process.

Thermokinetic investigation of the alcoholysis of acyl chlorides

The alcoholysis of acetyl chloride, propionyl chloride and butyryl chloride with some alcohols in acetone and toluene has been investigated by means of calorimetric measurements. Furthermore a comparison with benzoyl chloride has been made. In the case of i-propanol in acetone, a smaller rate constant has been found for the alcoholysis of propionyl chloride than for butyryl chloride. In contrast to this, almost equal rate constants have been determined for the reactions of these acyl chlorides with n-propanol and ethanol. In toluene, the rate constants for the reaction of acetyl chloride with all considered alcohols has the highest values under similar conditions but then decrease from acetyl chloride to butyryl chloride. The observed differences and the changes of rate constants are discussed and compared with literature data.

Tuning of the pitch height of thermotropic cellulose esters

Butyric esters of (2-hydroxypropyl) cellulose (BuPC) with different degree of substitution (DS) were synthesized via control of the esterification time of butyryl chloride and (2-hydroxypropyl) cellulose. These BuPCs are thermotropic and displayed different colors at ambient temperature due to the formation of a cholesteric structure and the occurrence of a corresponding cholesteric reflection. The pitch height was found to increase significantly with a decrease of the degree of substitution. Both the glass transition temperature and the melting temperature are not affected by variation of the DS. The BuPC samples displayed a banded texture or focal-conic texture, respectively. The X-ray diffraction studies revealed the presence of a layer structure. The d-spacing between two adjacent layers in the cholesteric structure displayed no significant dependence on the DS in the range from 2 to 3.

A Lewis Acid Site-Activated Reaction in Zeolites: Thiophene Acylation by Butyryl Chloride

The acylation of thiophene by butyryl chloride has been studied in the liquid phase in the presence of 12 catalysts: HZSM-5, H-mordenite, and HY (ultrastable Y) with various framework Si/Al ratios, various numbers of Brønsted and Lewis sites, and various amounts of nonframework aluminum. The numbers of Brønsted and Lewis acid sites were obtained by FT-IR using chemisorbed ammonia, as described elsewhere. There is a correlation between the initial rates of reaction and the number of Lewis acid sites, whereas there is no correlation between the initial rates and the number of Brønsted sites. The correlation with the number of Lewis sites may be considered significant, since it expands on more than one order of magnitude. Poisoning of the catalyst probably results from the oligomerization on butyryl chloride. No carboxylic acid has been detected in the course of the reaction. No attempt has been made to determine the nature of the poisoning reaction.

ChemInform Abstract: Synthesis of Oligo(3‐hydroxybutanoate)(OHB)‐Containing Peptides with High Binding Affinity to a Class‐I‐MHC Protein.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Synthesis of Oligo(3‐hydroxybutanoate)(OHB)‐Containing Peptides with High Binding Affinity to a Class‐I‐MHC Protein

AbstractIn the center of the immune system, there are major histocompatibility (MHC) protein/nonapeptide complexes which are recognized by T cell. The nonapeptides consist of three regions, an N‐terminal one containing three amino‐acid residues with a mandatory arginine in position 2, a C‐terminal one with a lysine or arginine in position 9, and a central, variable one of five residues (cf. Fig. 1). We have now synthesized the first conjugates (1–4) of oligopeptides with oligo[(R)‐3‐hydroxybutanoates] (OHB) as analogs of MHC‐binding peptides. Of the approaches chosen (Scheme 1), a fragment coupling of a hydroxy‐butanoyl‐amido ester (17 and 19) with an [(aminoalkanoyl)oxy]butanoyl chloride (27; Scheme 3), followed by two peptide‐coupling steps (Scheme 4), turned out to be most efficient. The conjugates H‐Gln‐Arg‐Leu‐(HB)3,4‐Lys‐OH (1 and 2) and H‐Ala‐Arg‐Leu‐(HB)3,4‐Lys‐OH (3 and 4) were thus obtained in pure form. The conjugates 1 and 2 with N‐terminal glutamine have a tendency to undergo cyclization with formation of a pyroglutamate residue (ef. Fig. 2). CD Measurements at different temperatures and so‐called epitope‐stabilization assays show that the complexes of the conjugates 2 and 4, containing four HB units, with the HLA‐B27 class‐I‐MHC protein are more stable than those of a model nonapeptide (C50 values of 2.25 and 1.60 μM vs. 10 μM), while the conjugates 1 and 3 with three HB units incorporated form less stable complexes (C50 values of 30 and 21 μM). The tetra(hydroxybutanoate)‐peptide conjugates 2 and 4 are the first nonapeptide analogs for which the modification of the central part leads to increased affinities for a class‐I‐MHC protein, as compared to a model nonapeptide.

Comment: A simple, low-cost, air-spray method for improved sample preparation for matrix-assisted laser desorption/ionisation mass spectrometry of derivatised poly(ethylene glycol)

A simple, low-cost, air-spray technique has been evaluated for the preparation of matrix-assisted laser desorption/ionisation (MALDI) sample slides. Hydroxyl end groups of poly(ethylene glycol) Mn = 600 were functionalised by esterification using acetyl and butyryl chlorides. Air-spray deposition gave excellent shot-to-shot and spot-to-spot reproducibility; the observed compositions by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) being in agreement with those obtained from 1 H NMR. Compressed air-spray is an excellent, inexpensive, sample preparation procedure for simple routine MALDI-TOF MS which increases the reproducibility of this increasingly important technique for synthetic polymer analysis.

ChemInform Abstract: The Enantiospecific Synthesis of (‐)‐Monomorine from L‐Glutamic Ester.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Study of the Pyridine 1-Oxide-Catalyzed Two-Phase Reversible Exchange Reaction of Benzoyl Chloride and Butanoate Ion

Abstract The reaction of benzoyl chloride (PhCOCl) and butanoate ion (PrCOO−) catalyzed by pyridine 1-oxide (PNO) in the medium H2O/CH2Cl2 leads to equilibrium with butanoyl chloride (PrCOCl) and benzoate ion (PhCOO−) and vice versa. The rate-determining step takes place in the organic phase and PrCOCl is much more reactive than PhCOCl. The effects of chloride ion, hydroxide ion, pyridine 1-oxide, reactants and temperature on the reaction rate and the equilibrium conversion of acyl chloride (RCOCl) were investigated. Satisfactory detailed mechanistic interpretations of the kinetic results are given.

Reactions of 2,3‐dihydro‐1H‐cyclohepta[b]pyrazines with acyl halides

Abstract2 When3‐dihydro‐1H‐cyclohepta[b]pyrazine (3) was treated with acetyl chloride under the Friedel‐Crafts conditions, its pyrazine ring opened to afford 2‐[N'‐acetyl‐(2‐aminoethyl)amino]tropone. Reactions with propionyl and butyryl chloride also gave similarly ring‐opened products. On the other hand, aromatic benzoyl chlorides reacted with compound 3 to afford N‐benzoyl‐substituted 2,3‐dihydro‐1H‐cyclohepta[b]pyrazines, in addition to ring‐opened compounds.

The enantiospecific synthesis of (-)-monomorine from L-glutamic ester

Diethyl L-glutamate hydrochloride ( 3) was converted to its N-pyrrole derivative 5. Submission of 5 to butyryl chloride in boiling toluene gave the 2-butyryl derivative, and by treatment with NaBH 3CN and ZnI 2, the 2-butyl analogue 9. Cyclization of 9 with BBr 3 afforded (5S)-3-butyl-5-ethoxycarbonyl-5,6-dihydro-8(7H)-indolizinone ( 10). Hydrogenation of 10 over Pd/C in acidified EtOH gave (3S,5S,9R)-3-butyl-5-ethoxycarbonylindolizidine. By successive reduction of the latter to the primary alcohol, formation of the chloride and reductive dechlorination with tributyltin hydride, (3S,5R,9R)-3-butyl-5-methylindolizidine, or (-)-monomorine, was obtained in 8 steps from 3 in a yield of 25%.

Yield improvement in the electrochemical production of perfluoro-octanoic acid

The possibility of obtaining real yield improvements in the industrial electrochemical production of perfluoro-octanoic acid is discussed on the basis of recent experimental data obtained using perfluorohexyl acetyl chloride in place of octanoyl chloride as a starting material. In particular, the effect of the non-formation of cyclic by-products on the yield of perfluoro-octanoic acid has been examined, as well as considering previous results obtained starting from a different partially fluorinated precursor, 4-perfluorobutyl butanoyl chloride. The yield of perfluoro-octanoic acid from perfluorohexyl acetyl chloride was less than expected, because of an accompanying increase in perfluoro-n-heptane formation.

The synthesis of carbon‐14 labeled pravastatin

AbstractAs asymmetric route to [14C]β‐hydroxycompactin 1 bearing the (S)‐2‐methyl‐[1‐14C]butanoate side chain has been developed. Methylation of [N‐[1‐14C]butyryl‐4‐(S)‐phenylmethyl‐2‐oxazolidinone 4 afforded a 95:5 mixture of diastereomeric [N‐(S,R)‐2‐methyl‐[1‐14C]butyryl]‐4‐(S)‐phenylmethyl‐2‐oxazolidinones 5,6 which were separated by preparative HPLC. Oxidative cleavage of 5 afforded optically pure (S)‐2‐methyl‐[1‐14C]butanoic acid. Acylation of alcohol 9 with optically pure (S)‐2‐methyl‐[1]14C]butyryl chloride afforded ester 10. Removal of the silyl either produced diastereomerically pure compactin 11. Hydroxylation was carried out by biotransformation with Mucor hiemelus to afford diastereomerically pure [[1‐14C]butanoate]β‐hydroxycompactin, [14C]Pravastatin 1.