Primary Alcohols Research Articles

The cuticular wax on sorghum straw influenced soil microbial diversity and straw degradation in soil

The cuticular waxes cover living plant surface but the ecological significance of cuticular wax in crop straw returning to soil remains uncertain. This study focused on sorghum straw to investigate the bioactivity of cuticular waxes in the soil system. The surface of sorghum leaf, sheath and stem organs was covered with epicuticular wax crystals, which present a dull and glaucous wax layer. The leaf surface with wax exhibited an average contact angle of 83°, while after the wax removal the contact angle decreased to 53° on average, showing hydrophobic surface on the sorghum leaf. In total, six wax classes were identified across all organs, including aldehydes, alkanes, fatty acids, primary alcohols, sterols, and minor triterpenoids. The total wax coverage on leaves was 1.5 μg·cm−2, which was significantly lower than that on sheaths (20.6 μg·cm−2) and stems (6.3 μg·cm−2). The wax addition increased the proportions of Actinobacteria and Firmicutes by 24.42 % and 78.02 %, whereas decreased Proteobacteria and Acidobacteria by 16.32 % and 23.16 % on day 14 under higher wax rate. The microbial communities inhabiting returned straw surfaces also differed significantly between wax-retrained and wax-removed straw, as well as among leaf, stem, and sheath components, and at various decomposition stages. Wax addition increased soil microbial biomass carbon and nitrogen by 56.76 % and 25.60 % at higher rate, and soil enzyme activities (i.e., soil urease, soil acid phosphatase activity, soil sucrase activity). Wax removal significantly increased the decomposition rate of dry matter by 24.28 % and crude fiber by 27.22 % on day 154. These findings demonstrate that plant cuticular waxes maintain their bioactivities after entering the soil, which broadens our knowledge of the roles of plant cuticular waxes in ecosystems. Therefore, selecting efficient wax-degrading microorganisms would accelerate the nutrient cycling of crops in soil system.

Influence of Cuticular Waxes from Triticale on Rumen Fermentation: A Metabolomic and Microbiome Profiling Study.

Cuticular wax, a critical defense layer for plants, remains a relatively unexplored factor in rumen fermentation. We investigated the impact of cuticular wax on rumen fermentation using triticale as a model. In total, six wax classes were identified, including fatty acids, aldehydes, alkane, primary alcohol, alkyresorcinol, and β-diketone, with low-bloom lines predominated by 46.05% of primary alcohols and high-bloom lines by 35.64% of β-diketone. Low-wax addition (2.5 g/kg DM) increased the gas production by 19.25% (P < 0.05) and total volatile fatty acids by 6.34% (P > 0.05), and enriched key carbohydrate-fermenting rumen microbes like Saccharofermentans, Ruminococcus, and Prevotellaceae, when compared to non-wax groups. Metabolites linked to nucleotide metabolism, purine metabolism, and protein/fat digestion in the rumen showed a positive correlation with low-wax, benefiting rumen microbes. This study highlights the intricate interplay among cuticular wax, rumen microbiota, fermentation, and metabolomics in forage digestion, providing insights into livestock nutrition and forage utilization.

Exploring the Intricacies and Functionalities of Galactose Oxidase: Structural Nuances, Catalytic Behaviors, and Prospects in Bio-electrocatalysis

Galactose Oxidase, also known as GOase, is an enzyme found mostly in Fusarium graminearum, Dactylium dendroides, and Gibberella fujikuroi. GOase, containing copper, serves catalytic functions in oxidizing substrates and primary alcohols such as d-galactose, benzyl alcohol derivatives, and dihydroxyacetone. The catalytic property of galactose oxidase that differentiates it from other enzymes is its cofactor consisting of a Cu (II)-bound Cys-Tyr* radical. The cofactor is vital for enabling regioselective oxidation. The application of galactose oxidase (GOase) covers several fields such as enzymatic synthesis, biosensors development, and processes of diagnosis.&#x0D; Galactose oxidase (GOase) was discovered to have a crystallographic structure by X-ray diffraction, which revealed an active site containing copper ions displaying relatively square pyramidal geometry. There are three unique structural and functional domains of the enzyme GOase. The domains include Tyr495 and a covalent bond between Cys228 and Tyr272 serving as equatorial and axial ligands, respectively. The mechanism of catalysis covers three different oxidation states, which include the active state containing Cu (II)-radical, the intermediate state containing Cu (II)-tyrosine, and the Cu(I)-tyrosine state. The cycle of catalysis that has been posited comprises several phases which are: (i) substrate binding, (ii) the transfer of proton (iii) the transfer of hydrogen atom, and (iv) subsequent oxidation steps. These phases eventually yield the synthesis of aldehyde and hydrogen peroxide.&#x0D; Galactose oxidase’s (GOase) mechanism of catalysis has been studied thoroughly via extensive research focusing on explaining the ping-pong mechanism that occurs in both oxidative and reductive half-reactions. The processes of activating and reactivating galactose (GOase) involve the transfer of electrons in which horseradish peroxidase (HRP) serves as an activator. The electrochemical investigations provide evidence of the electrochemical activation and reactivation of GOase in the presence of mediators.&#x0D; This comprehensive review enhances the comprehension of the structural complexities, catalytic mechanisms, and bio-electrocatalytic potential of GOase, thereby establishing a basis for future investigations and developments in technology.

Green, Solvent-Free Mechanochemical Synthesis of Nano Ag2O/MnO2/N-Doped Graphene Nanocomposites: An Efficient Catalyst for Additive-Base-Free Aerial Oxidation of Various Kinds of Alcohols.

Herein, we report a solvent-less, straightforward, and facile mechanochemical technique to synthesize nanocomposites of Ag2O nanoparticles-doped MnO2, which is further codoped with nitrogen-doped graphene (N-DG) [i.e., (X %)N-DG/MnO2-(1% Ag2O)] using physical milling of separately prepared N-DG and Ag2O NPs-MnO2 annealed at 400 °C over an eco-friendly ball-mill process. To assess the efficiency in terms of catalytic performance of the nanocomposites, selective oxidation of benzyl alcohol (BlOH) to benzaldehyde (BlCHO) is selected as a substrate model with an eco-friendly oxidizing agent (O2 molecule) and without any requirements for the addition of any harmful additives or bases. Various nanocomposites were prepared by varying the amount of N-DG in the composite, and the results obtained highlighted the function of N-DG in the catalyst system when they are compared with the catalyst MnO2-(1% Ag2O) [i.e., undoped catalyst] and MnO2-(1% Ag2O) codoped with different graphene dopants such as GRO and H-RG for alcohol oxidation transformation. The effects of various catalytic factors are systematically evaluated to optimize reaction conditions. The N-DG/MnO2-(1% Ag2O) catalyst exhibits premium specific activity (16.0 mmol/h/g) with 100% BlOH conversion and <99.9% BlCHO selectivity within a very short interval. The mechanochemically prepared N-DG-based nanocomposite displayed higher catalytic efficacy than that of the MnO2-(1% Ag2O) catalyst without the graphene dopant, which is N-DG in this study. A wide array of aromatic, heterocyclic, allylic, primary, secondary, and aliphatic alcohols have been selectively converted to respective ketones and aldehydes with full convertibility without further oxidation to acids over N-DG/MnO2-(1% Ag2O). Interestingly, it is also found that the N-DG/MnO2-(1% Ag2O) can be efficiently reused up to six times without a noteworthy decline in its effectiveness. The prepared nanocomposites were characterized using various analytical, microscopic, and spectroscopic techniques such as X-ray diffraction, thermogravimetric analysis, Fourier-transform infrared spectroscopy, Raman, field emission scanning electron microscopy, and Brunauer-Emmett-Teller.

Copper-catalyzed C(sp3)-H alkylation of fluorene with primary and secondary alcohols using a borrowing hydrogen method.

Despite the limited success of copper-catalyzed alkylations, (NNS)CuCl proved to be an effective catalyst for the sp3 C-H alkylation of fluorene with alcohols. Various primary alcohols and challenging secondary alcohols were successfully used. The practical applicability of the method was effectively tested with several post-functionalization reactions. This copper-catalyzed alkylation of fluorene involved a borrowing hydrogen mechanism.

One-pot three-component synthesis of α-methylated ketones from secondary and primary aryl alcohols

One-pot synthesis of α-methylated ketones from secondary and primary alcohols via a triple dehydrogenative method is presented.

Double dehydrogenative coupling of amino alcohols with primary alcohols under Mn(I) catalysis.

Herein, we unveil a method for synthesizing substituted pyrrole and pyrazine compounds via a double dehydrogenative coupling of amino alcohols with primary alcohols, facilitated by Mn(I)-PNP catalysis, which uniquely enables the simultaneous formation of C-C and C-N bonds.

Potent pincer-zinc catalyzed homogeneous α-alkylation and Friedländer quinoline synthesis reaction of secondary alcohols/ketones with primary alcohols.

Herein, we describe an air- and moisture-stable, homogeneous zinc catalyst stabilised using an electron deficient N^N^N pincer-type ligand. This ternary, penta-coordinated neutral molecular catalyst [Zn(N^N^N)Cl2] selectively produces α-alkylated ketone derivatives (14 examples) through a one-pot acceptorless dehydrogenative coupling (ADC) reaction between secondary and primary alcohols using the borrowing hydrogen (BH) approach in good to excellent isolated yields (up to 93%). It is worth noting that this catalyst also provides an eco-friendly route for the synthesis of quinoline derivatives (30 examples) using 2-aminobenzyl alcohols as alkylating agents via successive dehydrogenative coupling and N-annulation reactions. This cost effective, easy to synthesize and environmentally benign catalyst shows excellent stability in catalytic cycles under open-air conditions, as evident from its high turnover number (∼104), and is activated by using a catalytic amount of base under milder conditions.

Quinoline-derived NNP-manganese complex catalyzed α-alkylation of ketones with primary alcohols.

An air-stable quinoline-derived NNP ligand chelated Mn catalyst was developed for the efficient α-alkylation of ketones with primary alcohols via a hydrogen auto-transfer methodology. The sole by-product formed is water, rendering the protocol atom efficient. A wide range of ketone and alcohol substrates were employed, providing the α-alkylated ketones with isolated yields up to 94%. This system was also efficient for the green synthesis of quinoline derivatives while using (2-aminophenyl)methanol as an alkylating reagent.

NNN manganese complex-catalyzed α-alkylation of methyl ketones using alcohols: an experimental and computational study.

We present here a phosphine-free, quinoline-based pincer Mn catalyst for α-alkylation of methyl ketones using primary alcohols as alkyl surrogates. The C-C bond formation reaction proceeds via a hydrogen auto-transfer methodology. The sole by-product formed is water, rendering the protocol atom efficient. Electronic structure theory studies corroborated the proposed mechanism.

Preparation of a novel cadmium-containing coordination polymer and catalytic application in the synthesis of N-alkylated aminoquinoline derivatives via the borrowing hydrogen approach.

Herein, we report an efficient and straightforward approach for the synthesis of N-alkylated aminoquinoline derivatives by recyclable Cd-containing coordination polymer-catalyzed reactions of aminoquinolines with primary alcohols via the borrowing hydrogen strategy. In this work, a new type of coordination polymer [Cd(CIA)(phen)2(H2O)]n was successfully designed and fabricated. The molecular structure was corroborated by single-crystal X-ray diffraction and fully characterized by PXRD, FT-IR, TGA, and XPS. Importantly, this polymer revealed high catalytic activity for the N-alkylation reaction of 2-aminoquinoline and 8-aminoquinoline with inexpensive and low-toxicity alcohols as alkylating agents in excellent yields up to 95%. Interestingly, the present synthetic protocol was successfully applied for the gram-level synthesis of several biologically active compounds. In addition, several control reactions were carried out to investigate the possible mechanisms of this transformation. Finally, recycling experiments indicated that the cadmium coordination polymer showed good recovery performance for borrowing hydrogen reactions.

Experimental and theoretical insights for designing Zn2+ complexes to trigger chemo-selective hetero-coupling of alcohols.

Designing well-defined Zn-complexes for sustainable dehydrogenative catalysis overcoming the difficulties associated with activating Zn2+(d10)-metal species is considered paramount goal in catalysis. Herein, we explore the plausibility of β-alkylation of secondary alcohols with primary alcohols by well-defined 3d10 Zn-complexes. Detailed organometallic and catalytic investigations, in conjunction with computational analyses, were conducted to ascertain the potential involvement of the catalyst at various stages of the catalytic process.

α-Alkylation of ketones with primary alcohols by an active non-noble metal Cu/CuOx catalyst.

Development of convenient and effective heterogeneous non-noble metal catalysts for α-alkylation of ketones with alcohols is challenging in heterogeneous catalysis. Here, we report active non-noble metal Cu/CuOx catalysts for the construction of C-C bonds by the α-alkylation of ketones with alcohols through the borrowing hydrogen methodology. The optimal Cu/CuOx-250 catalyst exhibits good catalytic performance in the reactions to give the corresponding products in 50-96% yields. The Cu/CuOx catalysts are characterized by different analysis techniques such as XRD, TEM, XPS, H2-TPR, BET, and ICP. Moreover, the catalyst can be reused at least for five successive cycles without significant loss of activity. The present study provides meaningful insights into the development of non-noble metal heterogeneous catalysts for α-alkylation of ketones with alcohols.

BF3-promoted selective catalytic hydroboration of epoxides to primary alcohols

The novel BF3-promoted hydroboration of epoxides has been demonstrated; both homogeneous catalyst BF3·Et2O and heterogeneous catalyst BF3/HY exhibited remarkable catalytic activities for the synthesis of alkyl- and aryl-primary alcohols.

Cp*Ir(III) complexes catalyzed solvent-free synthesis of quinolines, pyrroles and pyridines via an ADC strategy.

A trio of Ir(III) complexes that are held together by a picolinamidato moiety were created. In our earlier research, we demonstrated the catalytic activity of the complexes for producing alpha-alkylated ketones from a ketone or secondary alcohol with a primary alcohol in the presence of a catalytic amount of a Cp*Ir(III) catalyst and tBuOK in toluene at 110 °C using the hydrogen-borrowing technique. Earlier many research groups had synthesized quinoline, pyrrole, and pyridine derivatives using 2-amino alcohol and ketone or secondary alcohol derivatives as starting materials, but in all those cases the reaction conditions are not suitable in terms of green synthesis like more catalyst loading, base loading, long reaction time, and high temperature. In addition, most of the reactions contain phosphine a hazardous by-product, along with the catalyst. Keeping in mind these shortcomings, we tried to expand the use of our catalysts after achieving an excellent result in our previous work, and we were successful in producing quinoline, pyrrole, and pyridine derivatives through acceptor-less dehydrogenative coupling (ADC) procedures at 90-110 °C under neat/solvent-free conditions and achieved good to exceptional yields of those nitrogen-containing heterocycles. This methodology is attractive because it is environmentally benign and allows for the "green" synthesis of nitrogen-containing heterocycles. All that is required is a modest quantity of catalyst and base, and the by-products are merely H2O and H2.

Catalytic utility of PNN-based MnI pincer complexes in the synthesis of quinolines and transfer hydrogenation of carbonyl derivatives.

This manuscript describes the synthesis of a triazolyl-pyridine-based phosphine, N-((diphenylphosphaneyl)methyl)-N-methyl-6-(1-phenyl-1H-1,2,3-triazol-4-yl)pyridin-2-amine, [2,6-{(PPh2)CH2N(Me)(C5H3N)(C2HN3C6H5)}] (1) (here onwards referred to as PNN) and its cationic and neutral MnI complexes and catalytic applications. The reaction of 1 with Mn(CO)5Br afforded a cationic complex [Mn(CO)3(PNN)]Br (2), which is highly stable in solid state, but in solution it gradually loses one of the CO groups to form a neutral complex [Mn(CO)2(PNN)Br] (3). Complex 2 on treatment with AgBF4 also yielded a cationic complex [Mn(CO)3(PNN)]BF4 (4). These complexes efficiently promoted the synthesis of quinoline derivatives via acceptor-less dehydrogenative coupling of 2-aminobenzyl alcohol and ketones, with complex 3 showing the highest activity with a very low catalyst loading (0.03 mol%) at 110 °C. Complex 3 (0.5 mol%) also showed excellent catalytic activity in the transfer hydrogenation of ketones and aldehydes to form respective secondary and primary alcohols.

Unsaturated sulfur-containing polymers from modular alcohol click chemistry

A modular and efficient click reaction for connecting primary and secondary alcohols with activated alkynes via carbonyl sulfide (COS) was developed. Polythiocarbonates were synthesized by the step-wise polyaddition of diols, dipropiolates, and COS.

Catalytic synthesis of carboxylic acids from oxygenated substrates using CO2 and H2 as C1 building blocks

A reaction system has been developed combining a reverse water–gas-shift-reaction and hydroxycarbonylation to produce carboxylic acids from renewable primary and secondary alcohols, ketones and aldehydes with CO2.

Screening of Process Parameters for Aspirin Loaded PLGA Microsphere

Background amp Aim Aspirin a non-steroidal anti-inflammatory drug has the potential to stimulate various dental stem cells and promotes regeneration of dental tissues. Polylactic glycolic acid PLGA a biocompatible and biodegradable polymer has the potential to stimulate multiple processes such as proliferation osteogenic differentiation initiation of mechanical support and formation of three-dimensional niches for the growth of new tissue. Hence this study aimed to identify the most effective formulation and process variables for developing aspirin polylactic glycolic acid microspheres using the Placket-Burman method.Method In the screening study Placket-Burman screening was systematically employed to estimate all of the parameter effects and interactions. The microspheres were formulated using the double-emulsion solvent extraction method by varying various variables and performing statistical analysis. Eight independent variables were considered for screening with encapsulation efficiency as the dependent variable. These variables included the volume of the internal phase of primary emulsion solvent system ethyl acetate ethanol homogenization time stirring speed emulsification time flow rate poly vinyl alcohol concentration and PLGA concentration.Results Encapsulation efficiency varied between 50.11 and 88.98. The concentration of PLGA and Poly vinyl alcohol and the volume of the internal phase were found to have a significant influence on encapsulation efficiency in the synthesis of Aspirin PLGA microsphere.Conclusion Among the eight independent variables assessed for screening the concentrations of PLGA and polyvinyl alcohol and the volume of the internal phase were found to significantly impact the encapsulation efficiency in the formulation of aspirin PLGA microspheres.

N-Alkylation of amines with primary/secondary alcohols using a novel cobalt(II) inverse triazolyl-pyridine complex.

Herein, we report a highly effective homogeneous methodology for the N-alkylation of amines with primary and secondary alcohols using a Co(II)-complex of an inverse triazolyl-pyridine ligand. The developed methodology tolerates various functional groups to produce the desired N-alkylated products in up to 98% yield. A number of control experiments establish that the developed methodology follows a hydrogen auto-transfer (HAT) pathway.