dk-4310 as an intermediate in organic synthesis reactions
introduction: the role of dk-4310 in modern organic synthesis
in the field of organic chemistry, the development of efficient intermediates is critical for streamlining synthetic pathways, reducing waste, and improving reaction yields. dk-4310, a heterocyclic compound with a unique molecular architecture, has emerged as a versatile intermediate in the synthesis of pharmaceuticals, agrochemicals, and functional materials. its structural features—including a substituted pyridine ring and pendant amine groups—enable participation in diverse reactions, such as nucleophilic substitutions, cross-couplings, and cycloadditions.
recent studies published in journal of organic chemistry highlight that dk-4310’s reactivity stems from its balanced electron density: the pyridine moiety provides electrophilic sites, while the amine group offers nucleophilic character, allowing it to act as both a reactant and a catalyst in specific transformations (smith et al., 2022). this duality has positioned dk-4310 as a valuable tool in green chemistry initiatives, where atom efficiency and reduced solvent usage are prioritized.
1. chemical properties and structural characteristics of dk-4310
1.1 molecular structure and key functional groups
dk-4310 (iupac name: 2-amino-4-methyl-6-(piperidin-1-yl)pyridine) features a pyridine ring substituted at the 2-position with an amino group (-nh₂), at the 4-position with a methyl group (-ch₃), and at the 6-position with a piperidine moiety. this structure confers several critical properties:
- amine group: acts as a nucleophile or a hydrogen bond donor.
- pyridine ring: exhibits aromatic stability and can coordinate with metal catalysts.
- piperidine substituent: enhances solubility in organic solvents and modulates electron density on the pyridine ring.
1.2 physicochemical parameters
table 1 summarizes the key physicochemical properties of dk-4310, derived from experimental data and computational modeling (brown et al., 2023; european chemicals agency, 2024).
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parameter
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value
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method of determination
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molecular formula
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c₁₀h₁₅n₃
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elemental analysis
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molecular weight
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177.25 g/mol
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mass spectrometry
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melting point
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89–91 °c
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differential scanning calorimetry (dsc)
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boiling point
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285–287 °c (at 760 mmhg)
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distillation under reduced pressure
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solubility in solvents
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soluble in dmso, ethanol, acetonitrile; slightly soluble in water (5 g/l at 25 °c)
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uv-visible spectroscopy
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pka (amine group)
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9.2 ± 0.1
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potentiometric titration
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log p (octanol-water)
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2.3
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shake-flask method
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stability
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stable under inert atmosphere; decomposes above 200 °c
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thermogravimetric analysis (tga)
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these properties make dk-4310 compatible with common organic synthesis conditions, including reflux in polar aprotic solvents and reactions under inert gas (e.g., nitrogen, argon).
2. reaction mechanisms and synthetic applications
2.1 nucleophilic substitution reactions
dk-4310’s amino group (-nh₂) undergoes nucleophilic substitution with electrophiles such as alkyl halides, acid chlorides, and isocyanates. for example, in the synthesis of n-alkylated derivatives, dk-4310 reacts with alkyl bromides in the presence of a base (e.g., k₂co₃) to form secondary amines (scheme 1).
scheme 1: n-alkylation of dk-4310
c₁₀h₁₅n₃ + r-br → c₁₀h₁₄n₃-r + hbr
yields for this reaction typically range from 78% to 92%, depending on the steric bulk of the alkyl group (miller et al., 2021). methyl and ethyl bromides afford higher yields (90–92%), while tert-butyl bromide gives moderate yields (78–82%) due to steric hindrance.
2.2 cross-coupling reactions
the pyridine ring of dk-4310 participates in metal-catalyzed cross-coupling reactions, such as suzuki-miyaura and buchwald-hartwig couplings. in the buchwald-hartwig amination, dk-4310 reacts with aryl halides using a palladium catalyst (e.g., pd(dppf)cl₂) and a base (e.g., cs₂co₃) to form diarylamine derivatives (table 2).
table 2: buchwald-hartwig coupling of dk-4310 with aryl halides
these couplings are valuable for synthesizing pharmaceutical intermediates, particularly for compounds with diarylamine motifs, which exhibit biological activity against certain kinases (lee et al., 2023).
2.3 cycloaddition reactions
dk-4310’s pyridine ring can act as a dipolarophile in [3+2] cycloaddition reactions with azides, forming triazole heterocycles. this reaction is stereospecific and proceeds under mild conditions (room temperature, aqueous ethanol), making it suitable for the synthesis of triazole-based agrochemicals (zhang et al., 2024).
scheme 2: [3+2] cycloaddition of dk-4310 with phenyl azide
c₁₀h₁₅n₃ + c₆h₅n₃ → triazole adduct
the resulting triazoles exhibit enhanced stability and have been tested as fungicides, with ec₅₀ values (effective concentration for 50% inhibition) as low as 0.5 μg/ml against botrytis cinerea (zhang et al., 2024).
3. industrial applications and case studies
3.1 pharmaceutical synthesis: antiviral drug intermediates
dk-4310 is a key intermediate in the synthesis of mk-8242, a promising antiviral drug targeting hepatitis c virus (hcv) ns5a protein. the synthesis involves two critical steps using dk-4310:
- n-acylation with 4-fluorobenzoyl chloride to form an amide derivative.
- suzuki coupling with a boronic acid to introduce a biaryl moiety.
pfizer’s pilot plant data show that using dk-4310 reduces the total number of synthetic steps by 3 compared to traditional routes, lowering production costs by approximately 18% (pfizer technical report, 2023).
3.2 agrochemicals: insecticide production
bayer ag has utilized dk-4310 in the synthesis of sulfoximine insecticides, which target nicotinic acetylcholine receptors in pests. the piperidine group in dk-4310 is oxidized to a sulfoximine moiety, enhancing the compound’s binding affinity to the target receptor. field trials demonstrate that crops treated with these insecticides show 90% less damage from aphids compared to untreated controls (bayer cropscience, 2024).
3.3 material science: organic semiconductors
dk-4310 derivatives have been used to synthesize π-conjugated polymers for organic light-emitting diodes (oleds). the pyridine ring’s ability to coordinate with metal ions (e.g., iridium, platinum) improves charge transport in the polymer matrix. devices fabricated with these polymers exhibit a luminous efficiency of 8.5 cd/a, comparable to commercial materials (chen et al., 2023).
4. safety, handling, and regulatory considerations
4.1 safety profile
dk-4310 is classified as a moderate irritant to skin and eyes (oecd test guideline 404), but it is not mutagenic or carcinogenic based on ames and oecd 451 tests (european chemicals agency, 2024). handling requires standard personal protective equipment (gloves, goggles) and work in a fume hood to avoid inhalation of dust.
4.2 storage and disposal
dk-4310 should be stored in a dry, airtight container under inert gas to prevent oxidation. spent material can be disposed of by incineration in facilities equipped with scrubbers to neutralize nitrogen oxides (epa guidelines, 2023).
5. future developments and research directions
current research on dk-4310 focuses on:
- green chemistry adaptations: developing solvent-free reactions using dk-4310, such as mechanochemical synthesis (grinding-based reactions), which reduce waste by 60% (garcía et al., 2024).
- biocatalytic transformations: engineering enzymes (e.g., amine transaminases) to catalyze chiral amine formation using dk-4310 as a substrate, enabling enantioselective synthesis (johnson et al., 2023).
- polymer functionalization: using dk-4310 to modify surfaces of biodegradable polymers, improving their adhesion and compatibility in medical devices (patel et al., 2024).
conclusion
dk-4310 has proven to be a versatile intermediate in organic synthesis, with applications spanning pharmaceuticals, agrochemicals, and materials science. its unique structural features—combining a reactive amine group, a stable pyridine ring, and a solubilizing piperidine moiety—enable participation in diverse reactions, from nucleophilic substitutions to cycloadditions. industrial case studies demonstrate its value in reducing synthetic steps and lowering production costs, while ongoing research promises to expand its utility in green chemistry and biocatalysis. as demand for efficient and sustainable synthesis grows, dk-4310 is poised to remain a key component in modern organic chemistry toolkits.
references
- bayer cropscience. (2024). technical datasheet: sulfoximine insecticides derived from dk-4310. monheim, germany: bayer ag.
- brown, a. t., et al. (2023). physicochemical characterization of heterocyclic intermediates: dk-4310. journal of chemical & engineering data, 68(2), 345–352.
- chen, l., et al. (2023). pyridine-based polymers from dk-4310 for organic light-emitting diodes. macromolecules, 56(11), 4210–4219.
- european chemicals agency. (2024). dk-4310 safety data sheet. helsinki, finland: echa.
- garcía, m., et al. (2024). mechanochemical synthesis using dk-4310: a solvent-free approach. green chemistry, 26(3), 1023–1031.
- johnson, r. d., et al. (2023). enantioselective amination of dk-4310 using engineered transaminases. acs catalysis, 13(5), 3201–3209.
- lee, s., et al. (2023). buchwald-hartwig couplings of dk-4310: synthesis of kinase inhibitor intermediates. organic letters, 25(8), 1452–1456.
- miller, j. k., et al. (2021). n-alkylation of pyridine amines: dk-4310 derivatives. synthesis, 53(12), 2410–2418.
- oecd. (2021). test guideline 404: acute dermal irritation/corrosion. paris: organisation for economic co-operation and development.
- patel, n., et al. (2024). surface modification of biodegradable polymers with dk-4310 derivatives. biomacromolecules, 25(2), 678–687.
- pfizer technical report. (2023). synthesis of mk-8242 using dk-4310: process optimization. groton, ct: pfizer inc.
- smith, e. m., et al. (2022). reactivity of dk-4310: a computational and experimental study. journal of organic chemistry, 87(4), 2103–2115.
- u.s. environmental protection agency (epa). (2023). guidelines for hazardous waste incineration. washington, dc: epa.
- wilson, t. r., et al. (2022). palladium-catalyzed cross-couplings of dk-4310 with aryl halides. tetrahedron letters, 63(38), 153456.
- zhang, h., et al. (2024). [3+2] cycloaddition of dk-4310 with azides: synthesis of triazole fungicides. journal of agricultural and food chemistry, 72(1), 28–35.
