Hexanoyl Chloride Research Articles

Esterification of lignin with long chain fatty acids for the stabilization of oil-in-water Pickering emulsions

Pickering emulsions offer numerous advantages over conventional surfactant-stabilized emulsion systems, including lower loading levels and enhanced long-term stability. Through both organic and inorganic Pickering emulsifying particles exist, more efforts are being invested in devising renewable, biodegradable, and non-toxic alternatives to conventional Pickering emulsifiers. In this study, the use of lignin (unmodified and esterified) specimens as an effective alternative to conventional Pickering emulsifiers was investigated. Hexanoyl chloride, decanoyl chloride, and palmitoyl chloride esterified lignin specimens were produced and their employability as Pickering emulsifiers was studied. The effects of varying the concentrations of lignin (unmodified and esterified specimens) and pH of the dispersion medium on the stability of the produced Pickering emulsions were explored. Comprehensive characterization of the esterified lignin stabilized Pickering emulsions exhibited enhanced stability, and smaller average oil droplet size, resulting in stable Pickering emulsions with high zeta potential and better flow properties. Overall, the studied esterified lignin specimens can have appealing applications in various Pickering emulsion systems, as a nontoxic and sustainable alternative to conventional emulsifiers.

Facile and efficient acylation of chitin in deep eutectic solvents

This study investigates acylation of chitin in deep eutectic solvents (DESs) as analogous solvents of ionic liquids (ILs), because we have already reported that such reaction smoothly progresses using acyl chlorides in the presence of pyridine/N,N-dimethyl-4-aminopyridine (DMAP) as base/catalyst in the IL, that dissolves chitin. In addition to a DES composed of 1-allyl-3-methylimidazolium chloride (AMIMCl) and thiourea (TUA) as hydrogen bond acceptor and donor (HBA and HBD), respectively, which we previously reported to dissolve chitin, several DESs were prepared from AMIMCl and different HBDs, that is, urea (UA), acetylthiourea (AcTUA), acetylurea (AcUA), and 1,1,3,3-tetramethylguanidine (TMG). These DESs were found to also dissolve chitin. Hexanoylation of chitin in the AMIMCl/TUA-DES under the same conditions, as those previously performed in the IL, i.e., using hexanoyl chloride in the presence of pyridine/DMAP at 100 ​°C for 24 ​h, gave the product with the low degree of substitution (DS). As this was speculated to be due to the high nucleophilicity of TUA, which had a potential to react with hexanoyl chloride, the other HBDs with lower nucleophilicity, mentioned above, were employed to be combined with AMIMCl in the DESs. When hexanoylation of chitin was carried out in the DESs composed of UA, AcTUA, AcUA, and TMG under the same conditions as above, the higher DS products were obtained. In particular, the reaction in the AMIMCl/TMG-DES efficiently occurred in the absence of pyridine/DMAP to produce the high DS product, probably owing to the high basicity and low nucleophilicity of TMG. The structure of the chitin hexanoate produced was evaluated by the IR and 1H NMR measurements. Accordingly, acylation of chitin using various acyl chlorides was performed in the AMIMCl/TMG-DES under the conditions without the use of pyridine/DMAP to give the corresponding chitin acylates with the high DSs. This study achieves the facile and efficient acylation method of chitin in the DES.

Ecofriendly Removal of Aluminum and Cadmium Sulfate Pollution by Adsorption on Hexanoyl-Modified Chitosan

The purity and safety of water as a finite resource is highly important in order to meet current and future human needs. To address this issue, the usage of environmentally friendly and biodegradable adsorbers and flocculants is essential. Chitosan, as a biopolymer, features tremendous properties as an adsorber and flocculant for water treatment. For the application of chitosan as an adsorber under acidic aqueous conditions, such as acid mine drainage, chitosan has been modified with hydrophobic hexanoyl chloride (H-chitosan) to reduce the solubility at a lower pH. In order to investigate the influence of the substitution of the hexanoyl chloride on the adsorption properties of chitosan, two chitosans of different molecular weights and of three different functionalization degrees were analyzed for the adsorption of CdSO4(aq) and Al2(SO4)3(aq). Among biobased adsorbents, H-chitosan derived from the shorter Chitosan exhibited extraordinarily high maximum adsorption capacities of 1.74 mmol/g and 2.06 mmol/g for Cd2+ and sulfate, and 1.76 mmol/g and 2.60 mmol/g for Al3+ and sulfate, respectively.

Synthesis of thermoplastic chitin hexanoate-graft-poly(ε-caprolactone)

Herein, we report that chitin hexanoate-graft-poly(ε-caprolactone) (ChHex-g-PCL) is thermoplastic, as confirmed by the formation of a melt-pressed film. Chitin hexanoates with degrees of substitution (DSs) of 1.4–1.8 and bearing free hydroxy groups were first prepared by the hexanoylation of chitin using adjusted feed equivalents of hexanoyl chloride in the presence of pyridine and N,N-dimethyl-4-aminopyridine in 1-allyl-3-methylimidazolium bromide, an ionic liquid. Surface-initiated ring-opening graft polymerization of ε-caprolactone from the hydroxy groups of the chitin hexanoates was conducted in the presence of tin(II) 2-ethylhexanoate as the catalyst at 100 °C to produce (ChHex-g-PCL)s. The feed equivalent of the catalyst, reaction time, and DS value were found to affect the molar substitution and degree of polymerization of the PCL graft chains. Longer PCL graft chains formed their crystalline structures and the (ChHex-g-PCL)s largely contained uncrystallized chitin chains. Accordingly, these (ChHex-g-PCL)s exhibited melting points associated with the PCL graft chains, leading to thermoplasticity.

A Complementary and Revised View on the N-Acylation of Chitosan with Hexanoyl Chloride.

The modification of the biobased polymer chitosan is a broad and widely studied field. Herein, an insight into the hydrophobization of low-molecular-weight chitosan by substitution of amino functionalities with hexanoyl chloride is reported. Thereby, the influence of the pH of the reaction media was investigated. Further, methods for the determination of the degree of substitution based on 1H-NMR, FTIR, and potentiometric titration were compared and discussed regarding their accuracy and precision. 1H-NMR was the most accurate method, while FTIR and the potentiometric titration, though precise and reproducible, underlie the influence of complete protonation and solubility issues. Additionally, the impact of the pH variation during the synthesis on the properties of the samples was investigated by Cd2+ sorption experiments. The adjusted pH values during the synthesis and, therefore, the obtained degrees of substitution possessed a strong impact on the adsorption properties of the final material.

Hydrophobization and Photo-Stabilization of Radiata Pinewood: The Effect of the Esterification on Thermal and Mechanical Properties

Wood protection through chemical modification has received increasing interest over the last decades due to the environmental issues related to conventional biocides or protecting products. Consequently, a wide range of new treatments are developed in laboratories, which are later scaled up in the industrial environment. The main goal of modifying wood for indoor–outdoor application is to change its hydrophilic character, which in turn improves the intrinsic properties of the material and its durability against external factors. Wood can be esterified through its hydroxyl groups to obtain a hydrophobic and photo-stable material. Chemical modifications of Pinus radiata D. Don wood using hexanoyl chloride (P6), dodecanoyl chloride (P12), and stearoyl chloride (P18) were carried out at different concentrations. Esterification was confirmed by Fourier Transform Infrared Spectroscopy (FTIR) technique combined with a discriminatory analysis. Weight percent gain was associated with the number of carbons of the aliphatic chain of the fatty acid (P6 > P12 > P18). Moreover, an increase of wood density as a consequence of modification treatments was observed. A substantial improvement of the hydrophobicity of wood was observed by dynamic contact angle measurements. In addition, the effect of ultraviolet (UV) radiation on color changes was reduced with the treatments. Furthermore, the P6 treatment presented acceptable values of modulus of elasticity (MOE) and modulus of rupture (MOR), being suitable for similar mechanical uses as non-treated pinewood. However, only treatments P12 and P18 enhanced thermal resistance of the pinewood in an oxidative atmosphere.

Development Of Novel Liposome-Encapsulated Combretastatin A4 Acylated Derivatives: Prodrug Approach For Improving Antitumor Efficacy.

PurposeThe objective of the present study was to develop a liposomal drug delivery system based on combretastatin A4 (CA4) prodrugs modified with varying alkyl chains and investigate the in vitro drug conversion from prodrug and in vivo antitumor effect.MethodsThe prodrug of CA4 was synthesized with stearyl chloride (18-carbon chain), palmitoyl chloride (16-carbon chain), myristoyl chloride (14-carbon chain), decanoyl chloride (10-carbon chain), and hexanoyl chloride (6-carbon chain) at the 3′-position of the CA4. Subsequently, it was encapsulated with liposomes through the thin-film evaporation method. Furthermore, the characteristics of prodrug-liposome were evaluated using in vitro drug release, conversion, and cytotoxicity assays, as well as in vivo pharmacokinetic, antitumor, and biodistribution studies.ResultsThe liposome system with loaded CA4 derivatives was successfully developed with nano-size and electronegative particles. The rate of in vitro drug release and conversion was reduced as the fatty acid carbon chain lengthened. On the contrary, in vivo antitumor effects were improved with the enlargement of the fatty acid carbon chain. The results of the in vivo pharmacokinetic and tissue distribution studies indicated that the reduced rate of CA4 release with a long carbon chain could prolong the circulation time and increase the drug concentration in the tumor tissue.ConclusionThese results suggested that the release or hydrolysis of the parent drug from the prodrug was closely related with the in vitro and in vivo properties. The slow drug release of CA4 modified with longer acyl chain could prolong the circulation time and increase the concentration of the drug in the tumor tissue. These effects play a critical role in increasing the antitumor efficacy.

Epigallocatechin gallate (EGCG) esters with different chain lengths fatty acids and their antioxidant activity in food and biological systems

Ester derivatives of epigallocatechin gallate (EGCG) were prepared by acylation with different chain lengths acyl chlorides, namely acetyl chloride, C2:0; propionyl chloride, C3:0; caproyl chloride, C6:0; capryloyl chloride, C8:0; lauroyl chloride, C12:0; stearoyl chloride, C18:0; and docosahexaenoyl chloride, C22:6. The resultant products, mainly tetra-esters, were purified and their lipophilicity, radical scavenging ability and antioxidant activities in food (bulk oil, β-carotene/linoleate emulsion and ground meat) and biological systems (LDL cholesterol and DNA) evaluated. The lipophilicity of the esters increased with increasing chain length of the acyl group and also led to the enhancement of their antioxidant properties. These findings strongly suggest that the EGCG ester derivatives have great potential as lipophilic alternatives to the water-soluble EGCG.

The effect of surface modification of microfibrillated cellulose (MFC) by acid chlorides on the structural and thermomechanical properties of biopolyamide 4.10 nanocomposites

Microfibrillated cellulose (MFC) has recently been identified as an innovative product of wood and agriculture industry with potential applications as reinforcement and carrier for functional properties of polymer composite materials, such as improved barrier and optical properties. The widespread commercial application of MFC in polymer technology still requires the development of new methods of MFC surface modifications in order to provide stong interfacial adhesion and good dispersibility of additive in polymer matrix. In this work microfibrillated cellulose was modified by acid chlorides arranged in a homologous series that showed high efficiency in changing the surface properties of the material. The modified MFC displayed hydrophobic character combined with preserved fibrillar morphology and high crystallinity. Chemical modification of MFC was assessed by Fourier transformed infrared spectroscopy (FTIR) and X-ray Photoelectron Spectroscopy (XPS) analyses. Despite the fact that the reactivity of acid chloride slightly decreased with increasing chain length the total effect on MFC wetting with water was most pronounced for the modifier with the longest alkyl chain. Completely bio-based engineering nanocomposites of biopolyamide 4.10 (PA4.10) and surface modified MFC were prepared by melt blending. Structural, morphological and thermomechanical analysis by scanning electron microscopy (SEM), atomic force microscopy (AFM) and dynamic mechanical analysis (DMA) methods evidenced clear dependence of composite performance on the length of alkyl chain attached to the MFC surface. The modification of MFC by hexanoyl chloride produced nanofiller with good dispersibility in PA4.10 matrix and was favorable in terms of dynamic mechanical properties of composites. While PA4.10 composites containing MFC functionalized by longer alkyl chains (more than 10 carbon atoms) showed a decrease of storage modulus due to insufficient interfacial interactions or plasticization effect.

Synthesis of Optically Active 15-epi-9,14-Methylene Lipoxin A4

The synthesis of lipoxin A4 and B4 analogues (LXA4, LXB4) to gain access to stabilized inflammation resolving compounds is an important field of research. Starting from known structural requirements of the natural compounds displaying biological activity and a broad investigation of their rapid metabolism, various LXA4 derivatives have been developed and tested. Focusing on variation and stabilization of the conjugated E,E,Z,E C7–C14 tetraene moiety of natural LXA4, a methylene bridge introduced between C9 and C14 might suppress any Z/E isomerization of the C11–C12 olefin. Intending to enable at least known structure variations in connection with the C1–C7 and the C15–C20 fragments, a convergent total synthesis starting from a known cycloheptatriene is developed. The C1–C8 building blocks are generated via six-step ex-chiral pool sequences starting from 2-deoxy-d-ribose delivering two 5,6-dihydroxy carboxylic acid derivatives with C7 aldehyde functions. The synthesis of the C8–C21 building block starts from a known cycloheptatriene 1-carbonester (C8–C14, C21) and hexanoyl chloride (C15–C20). After Friedel–Crafts-type coupling, the defined configuration of the C15 OH group is introduced via enantioselective reduction of the ketone precursor. Following an additional four steps, an aryl sulfone C9–C21 building block is completed ready for a key Julia–Kocienski olefination with the C1–C7 compounds. Finally, removal of the protecting groups completes the synthesis of the target optically active 9,14-methylene LXA4 methyl ester.

Thin Cellulose Nanofiber from Corncob Cellulose and Its Performance in Transparent Nanopaper

Cellulose separated from corncob was used as a new cellulose resource to produce esterified cellulose nanofiber (E-CNF) with hexanoyl chloride through one-step mechanochemical esterification by ball milling. The result showed that corncob cellulose was easily disintegrated and esterified to achevie a high DS, and then, thin nanofiber was compared to the common pulp cellulose resource. The DS of E-CNF was as high as 0.95, and the diameter was about 1.5–2.8 nm. Then, E-CNF was formed to nanopaper by vacuum filtration showing high optical transparency up to 89% at 550 nm. The transparent nanopaper had a Young’s modulus of 5.5 GPa and tensile strength of 110–125 MPa. Due to the introduction of alkyl chain, the wetting property of the nanopaper was changed from hydrophilicity to hydrophobicty. So, it may still work well in a humid environment.

Facile Synthesis of Crystalline Nanoporous GaN Templated by Nitrogen Enriched Mesoporous Carbon Nitride for Friedel‐Crafts Reaction

AbstractHighly crystalline nanoporous GaN (NP‐GaN) materials have been synthesized for the first time by the transformation of novel diamino tetrazine based mesoporous carbon nitride (MCN‐4) having very high nitrogen content (N/C ratio of 1.8) and GaCl3 through the unique reactive hard templating approach. Powder XRD and HRTEM analysis show that the prepared NP‐GaN is highly pure and possesses excellent crystallinity. N2 adsorption analysis confirm that the samples exhibit mesoporosity with excellent textural parameters including high specific surface areas. It is also demonstrated that NP‐GaN materials show excellent catalytic activity in the Friedel‐Crafts hexanoylation of benzene by using hexanoyl chloride (HC) with excellent conversion of HC. The activity of the NP‐GaN is also compared with MCN‐4, bulk Ga2O3 and GaN. Among the materials studied, NP‐GaN shows the highest catalytic performance in the above mentioned reaction with excellent conversion of HC and product selectivity to hexanophenone.

Hydrophobic cellulose films with excellent strength and toughness via ball milling activated acylation of microfibrillated cellulose

Cellulose films with excellent mechanical strength are of interest to many researchers, but unfortunately they often lack the ductility and water resistance. This work demonstrates an efficient and easily industrialized method for hydrophobic cellulose films made of modified microfibrillated cellulose (MFC). Prior to film fabrication, the simultaneous exfoliation and acylation of MFC was achieved through the synergetic effect of mechanical and chemical actions generated from ball milling in the presence of hexanoyl chloride. Largely enhanced tensile strength and elongation at break have been achieved (4.98MPa, 4.37% for original MFC films, 140MPa, 21.3% for modified ones). Due to hydrophobicity and compact structure, modified films show excellent water resistance and decreased water vapor permeability. Moreover, optical performance of modified films is also improved compared with the original MFC films. Our work can largely expand the application of this biodegradable resource and ultimately reduce the need for petroleum-based plastics.

Hydrophobically modified poly(vinyl alcohol) and boric acid-containing monoolein cubic phase as a glucose-responsive vehicle

Glucose-responsive monoolein (MO) cubic phase was prepared by including hydrophobically modified poly(vinyl alcohol) (HmPVA) and boric acid in its water channels. The covalent attachment of hexanoyl chloride (a hydrophobic modifier) to PVA was confirmed by 1H NMR and FT-IR spectroscopy. The viscosity of HmPVA/boric acid mixture solution (0.5% (HmPVA w/v)) in water/DMSO(1:1, v/v) increased significantly when the boric acid concentration increased to 3.2% (w/v). The viscosity of the HmPVA/boric acid mixture solution (0.5% (w/v)/0.8% (w/v)) decreased markedly when the glucose concentration increased to 400mg/dL. The interfacial tension in the plateau region of HmPVA solution, about 42dyn/cm, was lower than that of PVA solution, about 43dyn/cm, suggesting that HmPVA was more surface-active than PVA. According to the polarized optical microscopy, the phase transition temperature was found to be about 49.8°C. The release degree of amaranth (a dye) loaded in MO cubic phase containing HmPVA and boric acid was higher at a higher glucose concentration in the range of 0mg/dL⿿400mg/dL.

Reduction-responsive monoolein cubic phase containing hydrophobically modified poly(ethylene imine) and dithiodipropionic acid

Reduction-responsive MO cubic phase was prepared by including hydrophobically modified poly(ethylene imine) (HmPEI) and dithiodipropionic acid(DTPA) in the water channel of cubic phase. HmPEI(1:2) and HmPEI(1:5) were synthesized by a condensation reaction using reaction mixtures whose hexanoyl chloride to PEI molar ratio was 1:2 and 1:5, respectively. On the 1H NMR spectrum, the PEI to hexanoyl chloride molar ratio of HmPEI(1:2) and HmPEI(1:5) was evaluated to be 1:1.0 and 1:5.1, respectively. The light scattering intensity of PEI solution was negligible, but the light scattering intensity of HmPEI solution was significantly high, possibly due to the micellization. On the plot of concentration-dependent air/water interfacial tension, HmPEI with more hydrocarbon chains (HmPEI(1:5)) showed lower minimum interfacial tension and higher surface activity. MO cubic phases containing HmPEI and DTPA were prepared by hydrating MO melt with the mixture aqueous solution of HmPEI and DTPA. The cubic phases exhibited lamellar bilayers on TEM photos, and HmPEI and DTPA had little effect on the lamellar structure. The phase transition temperature of MO cubic phase, determined by polarized optical microscopy, was about 63.5°C, and HmPEI and DTPA had no significant effect on the phase transition temperature. This was in accordance with the result obtained with differential scanning calorimetry. The release profiles of Auramine O loaded in MO cubic phase containing HmPEI and DTPA resembled 1st order release. The release degree increased upon the addition of dithiothreitol, possibly because the disulfide bond of DTPA was cleaved and the network of HmPEI and DTPA was broken down by the reducing agent.

Surface and Bulk Transformation of Thermomechanical Pulp Using Fatty Acyl Chlorides: Influence of Reaction Parameters on Surface, Morphological, and Thermal Properties

A method is proposed for producing fatty acid esters of thermomechanical pulp (TMP) using fatty acids of intermediate chain length (C6-C12). The end objective is to use a stream of fatty acids produced via refining tall oil from Alberta's pulping mills. Depending on the degree of modification, these treated materials can serve either as reinforcement or as copolymers in composite applications. The effect of reaction conditions—reaction time, reaction temperature, fatty acyl concentration, and fatty acid chain length—on the degree of substitution of the pulp samples was studied. The reaction conditions were applied for each fatty acyl chloride and the pulp samples were characterized using X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, force tensiometry, time-of-flight secondary ion mass spectroscopy, atomic force microscopy, and thermal gravimetric analysis. The degree of substitution (DS) plateaued after two hours at a concentration of 0.25 M of hexanoyl chloride. These conditions were used for the other systems studied. The esterification of the pulp samples was heterogeneous as evident from both the AFM and SIMS images, because of the presence of lignin on the surface. Nevertheless, based on adhesion forces measured using AFM, the surface of the modified pulp samples was less polar. This was also confirmed via contact angle measurements. Also, the changes in chemical functionality were studied using FTIR and XPS with the appearance of peaks characteristic of C˭O (esters) and an increase in intensity of the alkyl shifts, respectively. Finally, it was found that esterification significantly improved the thermal properties of the pulp samples.

Metal-free mesoporous carbon nitride catalyze the Friedel–Crafts reaction by activation of benzene

Graphitic carbon nitride is an active and stable catalyst for Friedel–Crafts acylation of benzene with hexanoyl chloride.

Bonding behavior of hydrophobically modified gelatin films on the intestinal surface

The bonding behavior was determined for hydrophobically modified alkaline-treated gelatin on wet porcine intestinal surfaces. The modified gelatin films were obtained by reacting the amino groups of alkaline-treated gelatin with fatty acid chlorides of different alkyl chain lengths, namely, hexanoyl (Hx: C6) chloride, decanoyl (Dec: C10) chloride, and stearoyl (Ste: C18) chloride. Three kinds of the films were prepared, 32HxAlGltn, 24DecAlGltn, and 26SteAlGltn that had substitution ratios of hydrophobic groups to the amino groups of 32HxAlGltn, 24DecAlGltn, and 26SteAlGltn of 32%, 24%, and 26%, respectively. The 32HxAlGltn film had the strongest bonding to porcine intestinal surfaces. A thick 32HxAlGltn film remained on the intestinal surface even after the bonded film was scraped off for the measurement of bonding strength. In addition, the burst strength increased with an increase in the substitution ratio of the Hx group. Thus, the HxAlGltn film with the higher Hx modification ratio has a potential as a sealant material to prevent agglutination of intestinal surfaces.

Facile synthesis of acyl chitosan isothiocyanates and their application to porphyrin-appended chitosan derivative

Chitosan (1) was reacted with phenylisothiocyanate in 5% AcOH/H2O to give N-phenylthiocarbamoyl chitosan (2) with a degree of substitution (DS) of N-phenylthiocarbamoyl groups of 0.86 in 87.1% yield. The following acylation of compound 2 with hexanoyl chloride in the presence of pyridine afforded 3,6-di-O-2,3-hexanoyl chitosan isothiocyanate (4a) with a DS of the isothiocyanate groups of 0.70 in high yield, unexpectedly. Compound 4a exhibited high levels of reactivity toward various amines to give the corresponding N-thiocarbamoyl chitosan derivatives in high yields. Other acyl (decanoyl (4b), myristroyl (4c), stearoyl (4d), benzoyl (4e)) chitosan isothiocyanates were also prepared from chitosan (1) in high yields. To evaluate the potential applications of acyl chitosan isothiocyanates, N-(triphenylporphynyl)thiocarbamoyl chitosan derivative 6 with a DS of the triphenylporphynyl groups of 0.46 was prepared from compound 4b. The Langmuir–Blodgett monolayer film of compound 6 gave a good photon-to-electron conversion performance.

ChemInform Abstract: New and Efficient Synthesis of Amides from Acid Chlorides Using Diisobutyl(amino)aluminum.

Amides are valuable functional groups in biological, agrochemical, and pharmaceutical molecules. Several amides such as Weinreb amides, morpholine amides, and pyrrolidine amides are useful intermediates for the synthesis of aldehydes or ketones. Among them, morpholine amides are a cheap and good substitute for Weinreb amides. A large number of synthetic methods for making amides from various carboxylic acid derivatives have been reported. Among these, the aminolysis of acid chlorides in the presence of non-nucleophilic tertiary amines is generally considered to be the method of choice. Amides can also be synthesized using metals such as zinc, indium and samarium instead of tertiary amines from acid chlorides. Herein, we wish to report an alternative direct conversion of acid chlorides to secondary and tertiary amides (including morpholine amides), which proceeds under mild reaction conditions (0 °C) with an almost stoichiometric amount of amine and a short reaction time, and gives very good to excellent yields (Scheme 1). To demonstrate the feasibility of performing the desired reaction under a variety of conditions, we first carried out the synthesis of tertiary amides from benzoyl chloride. The corresponding morpholine amides could be obtained in 99% yield by reaction with benzoyl chloride under optimized reaction conditions in the presence of diisobutyl(morpholino)aluminum, which was easily prepared from morpholine and diisobutylaluminum hydride (DIBALH). The results are summarized in Table 1. We next synthesized various secondary and tertiary amides from other acid chlorides under the optimal conditions deduced from the previous experimental results. The results obtained for the reaction of benzoyl chloride with various primary and secondary amines are summarized in Table 2. As shown in Table 2, various noncyclic and cyclic primary amines underwent smooth conversion to the corresponding secondary amides in 90-99% yields (entries 1-5). Furthermore, the secondary amines also afforded the corresponding tertiary amides in 75-99% yields under similar reaction conditions (entries 6-10). From these results, we anticipated that the treatment of diisobutyl(morpholino)aluminum with representative acid chlorides would be effective for the direct synthesis of morpholine amides. Table 3 summarizes the results of the one-pot synthesis of morpholine amides from various acid chlorides. As expected, various aromatic acid chlorides with electronwithdrawing and electron-donating substituents underwent the conversion to the corresponding morpholine amides smoothly, in 89-99% yields (entries 1-7). A polyaromatic acid chloride such as naphthoyl chloride and a heterocyclic aromatic acid chloride such as furoyl chloride gave the corresponding morpholine amides in 92% and 91% yields, respectively, via the same methodology (entries 8 and 9). Furthermore, aliphatic acid chloride such as caproyl chloride smoothly afforded the corresponding morpholine amide in 96% under the same reaction conditions (entry 10). A proposed mechanism for this reaction is shown in Scheme 2 for the conversion of benzoyl chloride to the corresponding piperidine amide. Initially, the intermediate 2 is produced through the attack on the acid chloride by the secondary amino anion in diisobutyl(piperidino)aluminum 1 to give intermediate 3, with the release of an aluminum complex from intermediate 2. Finally, the hydrolysis of the Table 1. Optimization of reaction conditions for the synthesis of tertiary amides from acid chlorides