Decarboxylation Pathway Research Articles

Photocatalytic Oxidation of α‐Substituted Amines to Lactams/Amides

AbstractWe, herein, report a base free, photocatalytic decyanation of α‐aminonitriles. A range of amides and lactams were obtained in 52–95% yields. Control experiments indicate O2 as an amide/lactam oxygen source and the reaction (lactam formation) follows radical pathway via dioxetanimine species. This methodology also applied for α‐ester/aldehyde substituted pyrrolidines in the presence of a base, probably via decarboxylation pathway.

Novel insights into revealing the intrinsic degradation mechanism of ciprofloxacin by Chlorella sorokiniana: Removal efficiency, pathways and metabolism

Microalgae-mediated biodegradation of antibiotics has attracted increasing interest. However, the exact degradation mechanism behind it remains elusive, which is crucial for improving its efficiency and large-scale implementation. Therefore, this study aims to thoroughly investigate how Chlorella sorokiniana (C.sorokiniana) degrades ciprofloxacin (CIP) from the molecular level to elucidate its complicated degradation mechanism. Results show that C.sorokiniana exhibited an impressive removal rate of 38.05–74.29 % for CIP, the synergistic effect of biosorption and biodegradation was the main removal mechanism of CIP. The content of EPS increased by 11.84–103.31 %, acting as a carrier to increase the bioavailability of CIP. Enzyme activity analysis identified POD, CYP450, and GST as the major catalytic enzymes responsible for the biotransformation process of CIP with increases of 6–41.2 %, 18.78–102.1 % and 3.53–58.15 %, respectively. Molecular docking further revealed that the binding affinity of 146.24 μM, 27.71 μM and 16.33 μM was observed for POD,CYP450, and GST, respectively, indicating the high metabolic efficiency of CIP by CYP450. Finally, DFT calculations elucidated the enzyme-mediated biodegradation pathway of CIP, including hydroxylation, decarboxylation, and ring opening. These findings are expected to further fill the knowledge gap on the catalysis mechanism of CIP degradation by enzymes and improve the practical application of microalgae to antibiotic wastewater.

Catalytic Asymmetric Barbier Reaction of Ketones with Unactivated Alkyl Electrophiles.

The Barbier reaction is a reductive-type addition of an aldehyde or ketone with an organic electrophile in the presence of a terminal metal reductant, providing a straightforward and efficient method for carbon-carbon bond formation. This reaction possesses the advantage of circumventing the preparation of moisture- and air-sensitive organometallic reagents. However, the catalytic Barbier reaction of ketones to construct tetrasubstituted stereogenic centers is largely underdeveloped, despite its great potential for accessing synthetically challenging chiral tertiary alcohol. Particularly, the leveraging of unactivated alkyl electrophiles as coupling components is still rarely exploited. Herein, we disclose a photoredox-assisted cobalt-catalyzed asymmetric alkylative Barbier-type addition reaction of ketones to address the aforementioned challenges, thereby allowing for the construction of highly congested tetrasubstituted carbon centers. The alkyl addition fragments could be either readily accessible unactivated alkyl halides or redox-active esters generated through a decarboxylative pathway. Both types of alkyl electrophiles include primary, secondary, and tertiary ones, thus affording diverse enantioenriched tertiary alcohols with a broad substrate scope. This enantioselective protocol is applied for the expedient synthesis of core structure of Sofdra, a very recent FDA-approved drug in 2024. The newly developed bisoxazolinephosphine (NPN) ligand enables high enantioselectivity in this asymmetric reductive addition process.

Chemiosmotic nutrient transport in synthetic cells powered by electrogenic antiport coupled to decarboxylation

Cellular homeostasis depends on the supply of metabolic energy in the form of ATP and electrochemical ion gradients. The construction of synthetic cells requires a constant supply of energy to drive membrane transport and metabolism. Here, we provide synthetic cells with long-lasting metabolic energy in the form of an electrochemical proton gradient. Leveraging the L-malate decarboxylation pathway we generate a stable proton gradient and electrical potential in lipid vesicles by electrogenic L-malate/L-lactate exchange coupled to L-malate decarboxylation. By co-reconstitution with the transporters GltP and LacY, the synthetic cells maintain accumulation of L-glutamate and lactose over periods of hours, mimicking nutrient feeding in living cells. We couple the accumulation of lactose to a metabolic network for the generation of intermediates of the glycolytic and pentose phosphate pathways. This study underscores the potential of harnessing a proton motive force via a simple metabolic network, paving the way for the development of more complex synthetic systems.

Efficient degradation of haloacetic acids by vacuum ultraviolet-activated peroxymonosulfate: Kinetics, mechanisms and theoretical calculations

Efficient degradation of haloacetic acids (HAAs) is crucial due to their potential risks. This study firstly proposed vacuum ultraviolet - activated peroxymonosulfate (VUV/PMS) to remove HAAs (i.e., monochloroacetic acid (MCAA), monobromoacetic acid (MBAA), dichloroacetic acid (DCAA), etc). VUV/PMS achieved 99.51 % MCAA and 63.29 % TOC removal within 10 min. Electron paramagnetic resonance (EPR), quenching and probe experiments demonstrated that •OH was responsible for MCAA degradation. MCAA degradation followed pathways of dehalogenation (major) and decarboxylation (minor). VUV/PMS showed application potential under various reaction parameters. Broad spectrum of VUV/PMS on various HAAs was further explored. Chlorinated HAAs (Cl-HAAs) were primarily degraded by oxidation reactions, while brominated HAAs (Br-HAAs) by direct VUV photolysis. The density functional theory-based calculations (DFT) revealed that reaction rates of HAAs correlated with the highest occupied molecular orbital (HOMO) and energy gap (ΔE), indicating that HAAs degradation depends on their chemical structures. The Fukui function (f0 values) and bond length showed vulnerability of the halogen atom in Cl-HAAs and C–Br bond in Br-HAAs. Overall, this study provides an in-depth perspective on the oxidation performance and mechanism of HAAs using VUV/PMS. It not only demonstrates a green and efficient method but also inspires new strategies for HAAs remediation.

Identification and Characterization of Polyamine Metabolism in Citrus in Response to 'Candidatus Liberibacter asiaticus' Infection.

Citrus Huanglongbing, one of the most devastating citrus diseases, is caused by 'Candidatus Liberibacter asiaticus' (CLas). Polyamines are aliphatic nitrogen-containing compounds that play important roles in disease resistance and are synthesized primarily by two pathways: an arginine decarboxylation pathway and an ornithine decarboxylation pathway. However, it is unclear whether polyamines play a role in the tolerance of citrus to infection by CLas and, if so, whether one or both of the core polyamine metabolic pathways are important. We used high-performance liquid chromatography and ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry to detect the contents of nine polyamine metabolism-related compounds in six citrus cultivars with varying levels of tolerance to CLas. We also systematically detected the changes in polyamine metabolism-related compounds and H2O2 contents and compared the gene expression levels and the activities of enzymes involved in the polyamine metabolic pathway among healthy, asymptomatic, and symptomatic leaves of Newhall navel oranges infected with CLas. The tolerant and moderately tolerant varieties showed higher polyamine metabolism-related compound levels than those of susceptible varieties. Compared with the healthy group, the symptomatic group showed significantly increased contents of arginine, ornithine, γ-aminobutyric acid, and putrescine by approximately 180, 19, 1.5, and 0.2 times, respectively, and upregulated expression of biosynthetic genes. Arginase and ornithine decarboxylase enzyme activities were the highest in the symptomatic group, whereas arginine decarboxylase and agmatine deiminase enzyme activities were the highest in the asymptomatic group. The two polyamine biosynthetic pathways showed different trends with the increase of the CLas titer, indicating that polyamines were mainly synthesized through the arginine decarboxylase pathway in the asymptomatic leaves and were synthesized via the ornithine decarboxylase pathway in symptomatic leaves. These findings provide new insight into the changes in polyamine metabolism in citrus infected with CLas.

Formation of Volatile Pyrazinones in the Asparagine Maillard Reaction Systems and Novel Pyrazinone Formation Pathways in the Amidated-Alanine Maillard Reaction Systems.

Maillard reaction (MR) plays a pivotal role in the food flavor industry, including a cascade of reactions starting with the reaction between amino compounds and reducing sugars, and thus provides various colors and flavors. A new group of volatile compounds called pyrazinones found in MR are now getting more attention. In this study, eight volatile pyrazinones were found in the asparagine MR systems, in which 3,5-dimethyl- and 3,6-dimethyl-2(1H)-pyrazinones were reported for the first time. The major formation pathways were the reactions between asparagine and α-dicarbonyls, with decarboxylation as a critical step. Besides, novel alternative pathways involving alanine amidation and successive reactions with α-dicarbonyls were explored and successfully formed eight pyrazinones. The major differences between alanine-amidated pathways and decarboxylation pathways are the amidation step and absence of the decarboxylation step. For the alanine-amidated pathways, the higher the temperature, the better the amidation effect. The optimal amidation temperature was 200 °C in this study. The reaction between the alanine amide and α-dicarbonyls after amidation can happen at low temperatures, such as 35 and 50 °C, proposing the possibility of pyrazinone formation in real food systems. Further investigations should be conducted to investigate volatile pyrazinones in various food systems as well as the biological effects and kinetic formation differences of the volatile pyrazinones.

The Gut Microbiota in Parkinson Disease: Interactions with Drugs and Potential for Therapeutic Applications.

The concept of a 'microbiota-gut-brain axis' has recently emerged as an important player in the pathophysiology of Parkinson disease (PD), not least because of the reciprocal interaction between gut bacteria and medications. The gut microbiota can influence levodopa kinetics, and conversely, drugs administered for PD can influence gut microbiota composition. Through a two-step enzymatic pathway, gut microbes can decarboxylate levodopa to dopamine in the small intestine and then dehydroxylate it to m-tyramine, thus reducing availability. Inhibition of bacterial decarboxylation pathways could therefore represent a strategy to increase levodopa absorption. Other bacterial perturbations common in PD, such as small intestinal bacterial overgrowth and Helicobacter pylori infection, can also modulate levodopa metabolism, and eradication therapies may improve levodopa absorption. Interventions targeting the gut microbiota offer a novel opportunity to manage disabling motor complications and dopa-unresponsive symptoms. Mediterranean diet-induced changes in gut microbiota composition might improve a range of non-motor symptoms. Prebiotics can increase levels of short-chain fatty acid-producing bacteria and decrease pro-inflammatory species, with positive effects on clinical symptoms and levodopa kinetics. Different formulations of probiotics showed beneficial outcomes on constipation, with some of them improving dopamine levels; however, the most effective dosage and duration and long-term effects of these treatments remain unknown. Data from faecal microbiota transplantation studies are preliminary, but show encouraging trends towards improvement in both motor and non-motor outcomes.This article summarises the most up-to-date knowledge in pharmacomicrobiomics in PD, and discusses how the manipulation of gut microbiota represents a potential new therapeutic avenue for PD.

Computational-aided analysis of the pathway and mechanism of dichloroacetonitrile formation from phenylalanine upon chloramination

Dichloroacetonitrile (DCAN) is an emerging disinfection by-product (DBP) that is widespread in drinking water. However, the pathway for DCAN formation from aromatic amino acids remains unclear, leading to a lack of an understanding of its explicit fate during chloramination. In this study, we investigated the specific formation mechanism of DCAN during the chloramination of phenylalanine based on reaction kinetics and chemical thermodynamics. The reason for differences between aldehyde and decarboxylation pathways was explained, and kinetic parameters of the pathways were obtained through quantum chemistry calculations. The results showed that the reaction rate constant of the rate-limiting step of the aldehyde pathway with 1.9 × 10−11 s−1 was significantly higher than that of decarboxylation (3.6 × 10−16 s−1 M−1), suggesting that the aldehyde pathway is the main reaction pathway for DCAN formation during the chloramination of phenylalanine to produce DCAN. Subsequently, theoretical calculations were performed to elucidate the effect of pH on the formation mechanism, which aligned well with the experimental results. Dehydrohalogenation was found to be the rate-limiting step under acidic conditions with reaction rate constants higher than those of the rate-limiting step (expulsion of amines) under neutral conditions, increasing the rate of DCAN formation. This study highlights the differences in DCAN formation between the decarboxylation and aldehyde pathways during the chloramination of precursors at both molecular and kinetic levels, contributing to a comprehensive understanding of the reaction mechanisms by which aromatic free amino acids generate DCAN.

Generation of dichloroacetonitrile with the co-presence of g-C3N4 and chloride in peroxymonosulfate/Vis system: Impacts and mechanism

Monitoring and regulating the formation of toxic byproducts in advanced oxidation processes (AOPs) is of great significance for their practical application in water treatment. In this work, we found that dichloroacetonitrile (DCAN), a common N-containing byproduct in chloramination disinfection, can be formed with the co-presence of g-C3N4 and chloride in a peroxymonosulfate (PMS) system. The measured value was 12.01 μM within 12 h under the given conditions. Structure analysis of raw and used g-C3N4 demonstrated that g-C3N4 decomposition indeed occurred, and C = N bonds acted as primary active sites, releasing N resources for subsequent DCAN formation. Additionally, multiple parameters, including the reactant (i.e., g-C3N4, PMS, Cl-, phenol) dose and solution pH, were observed to remarkably affect the yield of DCAN. Phenol was identified as the organic precursor of DCAN and may cooperate with inorganic chloramine to promote DCAN formation via the decarboxylation pathway. This study highlights the generation of DCAN in N-involved catalyst-based AOPs and improves understanding of the DCAN formation mechanism.

Iron-Mediated Electrolysis for Selective Oxidative Decarboxylation of C-Terminal Acids Using Metal-Binding Residue

With the increasing concern of the environmental impact of solid-phase peptide synthesis (SPPS), semi-recombinant processes, in which recombinantly expressed peptides are selectively modified, are of growing interest. The strategies employed for these modifications must overcome the challenges associated with recombinant peptides: selectivity across many functional groups and solubility of the full-length peptide. Electrochemistry is a viable solution to these challenges as it is a mild and tunable process which can operate in both organic and aqueous systems. Herein, a model tetramer with a redox-active residue, tyrosine, is selectively decarboxylated at the C-terminus in an iron-mediated electrolysis. Chemoselectivity is achieved by exploiting the metal-binding property of a C-terminal glutamic acid residue. In the presence of the iron mediator, the tyrosine oxidation pathway is suppressed while the oxidative decarboxylation pathway is favored. Mechanistic controls demonstrate that the glutamic acid, iron, and applied current are all necessary to impart the desired chemoselectivity.

One-electron oxidant-induced transformation of dissolved organic matter: Optical and antioxidation properties and molecules

Dissolved organic matter (DOM) is a major sink of radicals in advanced oxidation processes (AOPs) and the radical-induced DOM transformation influences the subsequent water treatment processes or receiving waters. In this study, we quantified and compared DOM transformation by tracking the changes of dissolved organic carbon (DOC), UVA254, and electron donating capacity (EDC) as functions of four one-electron oxidants (SO4•−, Cl2•−, Br2•−, and CO3•−) exposures as well as the changes of functional groups and molecule distribution. SO4•− had the highest DOC reduction while Cl2•− had the highest EDC reduction, which could be due to their preferential reaction pathways of decarboxylation and converting phenols to quinones, respectively. Br2•− and CO3•− induced less changes in DOC, UVA254, and EDC than SO4•− and Cl2•−. Additionally, DOM enriched with high aromatic contents tended to have higher DOC, UVA254, and EDC reductions. Decreases in hydroxyl and carboxyl groups and increases in carbonyl groups were observed in these four types of radicals treated DOM using Fourier transform infrared spectroscopy. High resolution mass spectrometry using FTICR-MS showed that one-electron oxidants preferred to attack unsaturated carbon skeletons and transformed into molecules featuring high saturation and low aromaticity. Moreover, SO4•− was inclined to decrease oxidation state of carbon and O/C of DOM due to its strong decarboxylation capacity. This study highlights the distinct DOM transformation by four one-electron oxidants and provides comprehensive insights into the reactions of one-electron oxidants with DOM.

Riboflavin-loaded carbon cloth aids the anaerobic digestion of cow dung by promoting direct interspecies electron transfer

Cow dung generates globally due to increased beef and milk consumption, but its treatment efficiency remains low. Previous studies have shown that riboflavin-loaded conductive materials can improve anaerobic digestion through enhance direct interspecies electron transfer (DIET). However, its effect on the practical anaerobic digestion of cow dung remained unclear. In this study, carbon cloth loaded with riboflavin (carbon cloth-riboflavin) was added into an anaerobic digester treating cow dung. The carbon cloth-riboflavin reactor showed a better performance than other two reactors. The metagenomic analysis revealed that Methanothrix on the surface of the carbon cloth predominantly utilized the CO2 reduction for methane production, further enhanced after riboflavin addition, while Methanothrix in bulk sludge were using the acetate decarboxylation pathway. Furthermore, the carbon cloth-riboflavin enriched various major methanogenic pathways and activated a large number of enzymes associated with DIET. Riboflavin's presence altered the microbial communities and the abundance of functional genes relate to DIET, ultimately leading to a better performance of anaerobic digestion for cow dung.

Ascorbic acid-enhanced Fe(III)/peracetic acid process for the degradation of diclofenac: Treatment efficiency, mechanism and influencing factors

To overcome the sluggish reduction from Fe(III) to Fe(II) and excessive iron sludge production in Fe(III)/peracetic acid (PAA) process, ascorbic acid (AA), an environmental-friendly and natural reductant, was proposed in this study to boost the oxidation ability of Fe(III)/PAA process by facilitating the cycling of Fe(III)/Fe(II). AA-enhanced Fe(III)/PAA process exhibited remarkable acceleration in the degradation of diclofenac (DCF), with the removal rate of DCF being around 51 times higher than that without AA. Multiple reactive species of FeIVO2+, R-O, and OH were involved in the abatement of DCF in the AA/Fe(III)/PAA process. FeIVO2+ was confirmed as the predominant contributor for the elimination of DCF, whereas R-O and OH also participated in DCF abatement. In the AA-enhanced Fe(III)/PAA process, AA rapidly complexed with Fe(III) to produce the Fe(III)-AA complex, which was subsequently decayed to generate Fe(II), and then reactive species were generated by activating PAA with Fe(II) to degrade DCF through the pathways of dichlorination-cyclization, decarboxylation, and hydroxylation. The acute toxicity of the reaction solution employing BioFixlumi as a toxicity indicator decreased with the abatement of DCF. Common inorganic ions, including Cl−, SO42−, CO32−, and NO3−, had no adverse influence on DCF degradation, while humic acid and common cations (Zn2+, Ca2+, and Mg2+) inhibited DCF abatement. AA/Fe(III)/PAA process was highly effective for DCF removal in actual water samples, including surface water and underground water. AA/Fe(III)/PAA process was prone to degrading micropollutants with higher fractions of deprotonated species and lower ionization potentials, and performed with high selectivity towards micropollutants. Overall, the outstanding oxidation capacity and environmental friendliness of AA/Fe(III)/PAA process render it a potential technology to remove micropollutants in wastewater treatment.

The role of decarboxylation reactions during the initiation of the methanol-to-olefins process

The mechanism for direct CC bond formation during the initiation of the methanol-to-olefins (MTO) process is still under discussion. Carbon dioxide formation is often observed during initiation, but there are only few investigations into the role of decarboxylation. We investigate decarboxylation pathways in the H-SSZ-13 zeolite from methanol to olefins via direct carbon–carbon coupling. Additionally, the rate-determining steps were recomputed in the H-ZSM-5 and H-SAPO-34 zeolite. Gibbs free energy barriers were calculated using periodic density functional theory in combination with CCSD(T) calculations on cluster models. For H-SSZ-13, kinetic batch reactor simulations were performed. We found for H-SSZ-13 that pathways via decarboxylation reactions are equally likely as previously computed pathways including decarbonylation mechanisms (also known as ketene or CO pathway). Lactones formed from ketenes and formaldehyde were identified as the main intermediates. The decarboxylation mechanism has similar barriers in H-SSZ-13, H-ZSM-5, and H-SAPO-34, while the barriers for methylation and decarbonylation reactions are significantly lower in H-ZSM-5 and higher in H-SAPO-34. Decarboxylation reactions of lactones could explain experimentally detected carbon dioxide during the initial phase of the MTO process.

Decarboxylative - Dimerization of levulinic acid using spent Li-ion battery electrode material with lithium nickel cobalt manganese oxide as a catalyst

A low cost catalyst prepared by pyrolyzing electrode coating material from spent Li-ion battery cells was shown as an effective catalyst for the decarboxylative - dimerization of levulinic acid to a mixture of C6 and C9 fuel precursors. The highest levulinic acid conversion of 94% was observed with 10% (w/w) catalyst loading under 1.24 MPa H2 at 140 °C, 15 h. A reaction scheme was proposed to explain the novel transformation producing C9 lactone products and C6 unsaturated alcohol product through a decarboxylative pathway followed by the aldol dimerization of levulinic acid.

Unraveling the decarboxylation dynamics of the fluorescein dianion with fragment action spectroscopy

The decarboxylation dynamics of the doubly deprotonated fluorescein dianion, Fl2-, are investigated by recording fragment action spectra for the anion, Fl-, and its decarboxylated analog, Fl-CO2-, using a new reflectron secondary mass spectrometer. The formation of the anion, Fl-, is directly investigated by photoelectron imaging. The Fl- and Fl-CO2- action spectra indicate that, for λ < 400nm, one-photon dissociative photodetachment, i.e., simultaneous decarboxylation and electron loss, competes with photodetachment, whereas for λ > 400nm, decarboxylation only proceeds following electron loss via a sequential two-photon process. The primary decarboxylation pathway is the ready loss of CO2 from the relatively short-lived intermediate excited state, Fl-[D1], which is formed by electron loss from the dianion via resonant tunneling through the repulsive Coloumb barrier associated with a high-lying excited dianion state, Fl2-[S2].

Merging Photocatalytic C–O Cross-Coupling for α-Oxycarbonyl-β-ketones: Esterification of Carboxylic Acids via a Decarboxylative Pathway

Herein, the first merged photocatalytic pathway for the C-O cross-coupled esterification of carboxylic acids to α-oxycarbonyl-β-ketones has been demonstrated. Decarboxylation of α,β-unsaturated acids promotes the formation of the β-ketone fragment of the desired product. Water as the source of oxygen for the ketone segment and aerial oxygen as an oxidant make the present synthetic methodology green and sustainable. This new C═O and C-O bond-forming methodology takes place in a cascade manner under a dual Ir/Pd-catalytic pathway, with the liberation of H2O and CO2 as the only byproducts.

Highly stable Mo-based bimetallic catalysts for selective deoxygenation of oleic acid to fuel-like hydrocarbons

To develop efficient, economical and environmentally friendly Mo-based bimetallic Al/MCM-41 catalysts for catalytic oleic acid pyrolysis into hydrocarbon-like upgrading biofuel, a series of metal-modified Mo-based catalysts was successfully synthesized. The effects of different metal oxide types (Zr, Zn, Pt, Cu, Co, Ce, Ni) and Ce to Mo mixed ratios were compared and characterized by XRD, BET, NH3-TPD, XPS, SEM and TEM technologies. Simultaneously, the deoxygenation effect and reusability properties were also evaluated by Py-GC/MS and TGA. The results showed that the molybdenum-based bimetallic catalyst exhibited superior deoxygenation activity (Ce>Cu>Zn>Ni>Zr∼Pt>Co) in the decarbonylation and decarboxylation pathways. Higher deoxygenation activity was related to rich surface Ce-□-Mo synergistic oxygen vacancies, suitable metal-Lewis and Brønsted acidity and excellent textural properties. A higher Ce content was beneficial to HC and aromatic formation due to a higher specific surface area and mesoporous volume, and a higher Mo content facilitated olefin and alkane conversion due to a higher Brønsted acid intensity and smaller pore size. The 3Ce-1Mo/Al-MCM-41 exhibited excellent catalytic activity and promising reusability by yielding 97.72% hydrocarbons, 75.33% aromatic content and 57.92% MAHs due to the synergistic effect between Ce and MoOx, rich surface Ce-□-Mo synergistic oxygen vacancies and suitable metal-Lewis and Brønsted acid intensities that contributed to better reaction activity and coke resistance and activated the CO of oleic acid. The slight reduction in HCs was mainly due to the loss of active metal sites and coke deposition. Furthermore, the synergistic effect of Ce and MoOx species obviously advanced the reaction activity and coke resistance.

Unexpected formation of 2-methyl-1H-naphtho [2, 3-d] imidazole via decarboxylation governed mechanistic pathway

Present work is the outcome of the synthetic strategy for the naphthalene analogue of benzimidazole dimer, 2-methyl-1H-naphtho [2, 3-d] imidazole. It was found that 1H-naphtho [2, 3-d] imidazol-2-yl) methane (2b') was formed instead of respective dimer. Herein, we have reported two synthetic ways for 2b', first conventional refluxing method with 70 % yield and second by using synthesis reactor with 75 % yield. Both the way of synthesis involves the reaction of 2,3- diamino naphthalene and diethyl malonate in acidic medium. This example belongs to C-2(sp2)-C-1(sp3) type decarboxylation. To the best of our knowledge, it is the first-time synthesis of the 2b‘ has been reported via decarboxylation pathway along with crystal structure and DFT studies. Most probable mechanisms for both the compounds have been proposed based on the energy profile diagram and thermodynamic data obtained by DFT calculations [B3LYP/6-311++G (d,p)] in gas phase. Absorption responses showed potential of the naphthaimidazole based molecule 2b‘ as a pH and metal ion sensor of various hazardous metals such as As3+, Cr3+, Hg2+,Cd2+, Pb2+.