Hubbry Logo
Geminal diolGeminal diolMain
Open search
Geminal diol
Community hub
Geminal diol
logo
8 pages, 0 posts
0 subscribers
Be the first to start a discussion here.
Be the first to start a discussion here.
Geminal diol
Geminal diol
Geminal diol
View on Wikipedia
from Wikipedia
The generic geminal diol. The 'R's represent any groups other than OH.

A geminal diol (or gem-diol for short) is any organic compound having two hydroxyl functional groups (−OH) bound to the same carbon atom. Geminal diols are a subclass of the diols, which in turn are a special class of alcohols. Most of the geminal diols are considered unstable.

The simplest geminal diol is methanediol CH4O2 or H2C(OH)2. Other examples are:

Reactions

[edit]

Hydration equilibrium

[edit]

Geminal diols can be viewed as ketone (or aldehyde) hydrates. The two hydroxyl groups in a geminal diol are easily converted to a carbonyl or keto group C=O by loss of one water molecule. Conversely, a keto group can combine with water to form the geminal hydroxyl groups.

The equilibrium in water solution may be shifted towards either compound. For example, the equilibrium constant for the conversion of acetone (H3C)2C=O to propane-2,2-diol (H3C)2C(OH)2 is about 10−3,[1] while that of formaldehyde H2C=O to methanediol H2C(OH)2 is 103.[2]

For conversion of hexafluoroacetone (F3C)2C=O to the diol (F3C)2C(OH)2, the constant is about 10+6, due to the electron withdrawing effect of the trifluoromethyl groups. Similarly, the conversion of chloral (Cl3C)HC=O to chloral hydrate is strongly favored by influence of the trichloromethyl group.

In some cases, such as decahydroxycyclopentane and dodecahydroxycyclohexane, the geminal diol is stable while the corresponding ketone is not.

Geminal diols can also be viewed as extreme cases of hemiacetals, formed by reaction of carbonyl compounds with water, instead of with an alcohol.

See also

[edit]

References

[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia

Geminal diol

View on Grokipedia
from Grokipedia
A geminal , also known as a gem-diol, is an in which two hydroxyl (-OH) groups are attached to the same carbon atom, distinguishing it from vicinal diols where the groups are on adjacent carbons. These compounds typically form through the reversible of water to the (C=O) of aldehydes or ketones, resulting in a tetrahedral structure with the formula R₂C(OH)₂, where R can be hydrogen, alkyl, or other substituents. Geminal diols are generally unstable under normal conditions and tend to dehydrate back to the parent carbonyl compound, establishing an equilibrium that favors the carbonyl form for most aldehydes and nearly all ketones due to the strain in the geminal arrangement and the stability of the C=O bond. However, stability increases with electron-withdrawing groups adjacent to the carbon or in cases of small substituents; for instance, formaldehyde (H₂C=O) exists predominantly as its hydrate, methanediol (H₂C(OH)₂), in aqueous solution, forming the basis of formalin, a common preservative. Other notable stable examples include chloral hydrate (Cl₃CCH(OH)₂), used historically as a sedative, and ninhydrin hydrate, employed in forensic analysis for detecting amino acids. The formation of diols can be catalyzed by acids or bases, with the mechanism involving of the carbonyl oxygen in acidic conditions or direct nucleophilic attack by in basic conditions, followed by proton transfer steps to yield the . In , they are named as alkane-x,x-diols under IUPAC rules, where "x,x" indicates the geminal positions (e.g., ethane-1,1-diol for ), though they are more commonly referred to as hydrates of the corresponding carbonyl. Beyond laboratory synthesis, diols play crucial roles as transient intermediates in , such as in the of alkenes and the cycling of Criegee intermediates, and have been detected in interstellar ices through advanced spectroscopic methods. Their reactivity underscores their importance in and environmental processes, where they can further react to form acetals, hemiacetals, or other derivatives under appropriate conditions.

Structure and Properties

Molecular Structure

A geminal is an featuring two hydroxyl groups (-OH) attached to the same carbon atom, resulting in a characteristic C(OH)2 unit. These compounds are also known as carbonyl hydrates, formed by the addition of across a carbonyl bond. The general is R1R2C(OH)2, where R1 and R2 may represent , alkyl, aryl, or other substituents. In geminal diols, the central carbon atom adopts a tetrahedral due to its sp3 hybridization, with four single bonds to the two oxygen atoms and the two substituents. This contrasts with the precursor carbonyl compound, where the carbon is sp2 hybridized, forming a trigonal planar structure around the C=O bond. The tetrahedral arrangement positions the substituents at approximate bond angles of 109.5°, though from the adjacent hydroxyl groups can cause deviations; for instance, in the simplest geminal diol, (H2C(OH)2), the O-C-O angle measures 112.6°, the H-C-H angle 110.2°, and O-C-H angles 105.3°. Typical bond lengths in geminal diols reflect standard single bonds in alcohols: the C-O bonds are approximately 1.42 , while O-H bonds are about 0.96 , as observed in with C-O at 1.408 and O-H at 0.964 . These values underscore the saturated, non-conjugated nature of the carbon-oxygen linkages. Geminal diols are commonly represented in structural formulas as R1R2C(OH)2, highlighting the positioning of the hydroxyl groups. In Lewis dot structures, the central carbon achieves an octet through four bonds, with each oxygen bearing a and forming a polar O-H bond; for , the structure exhibits Cs or C2 symmetry depending on the conformer.

Physical and Chemical Properties

Most diols exhibit inherent instability under neutral conditions, tending to spontaneously to their corresponding carbonyl compounds due to the reversibility of the hydration equilibrium. The stability of diols is significantly influenced by substituents on the carbon atom bearing the two hydroxyl groups; strong electron-withdrawing groups, such as , stabilize the diol form through inductive effects that reduce on the carbon, making less favorable, as exemplified by (2,2,2-trichloroethane-1,1-diol), which exists as a stable crystalline solid. In contrast, () demonstrates notable stability in primarily owing to minimal steric hindrance from its small substituents, allowing for effective hydration without significant repulsion. Geminal diols typically appear as colorless liquids or solids and exhibit high in , attributable to extensive hydrogen bonding between the hydroxyl groups and molecules. In terms of spectroscopic properties, geminal diols display a broad absorption band for the O-H stretch in the range of 3200–3600 cm⁻¹, characteristic of hydrogen-bonded hydroxyl groups, along with the absence of the C=O stretch near 1700 cm⁻¹ that is typical of their carbonyl precursors. In , symmetric geminal diols such as show a single signal for the two equivalent hydroxyl protons due to . The acidity of the hydroxyl groups in diols is moderately enhanced compared to simple alcohols, with pKa values typically ranging from 12 to 14; this shift arises from the arrangement, where the adjacent hydroxyl group exerts an electrostatic effect that facilitates , as seen in with a pKa of approximately 13.3.

Formation and Synthesis

Hydration of Carbonyl Compounds

The primary method for generating geminal diols involves the of water to the of aldehydes and ketones, forming a reversible equilibrium. The general reaction is represented as: R2C=O+H2O⇌R2C(OH)2\mathrm{R_2C=O + H_2O \rightleftharpoons R_2C(OH)_2} where the equilibrium typically favors the carbonyl compound for most ketones and simple aldehydes under standard conditions. This addition proceeds via an acid- or base-catalyzed mechanism. In the acid-catalyzed pathway, a proton from a dilute acid, such as HCl, first protonates the carbonyl oxygen, increasing the electrophilicity of the carbon atom and facilitating nucleophilic attack by water. This generates an intermediate , which undergoes proton transfer to yield the geminal diol. In the base-catalyzed mechanism, ion (OH⁻) acts as the , adding directly to the electrophilic carbonyl carbon to form a tetrahedral intermediate, followed by proton transfer from water to restore neutrality. The reaction typically occurs in aqueous solutions at , with higher —such as in concentrated solutions or under high humidity—shifting the equilibrium toward hydrate formation. Hydration is more favorable for aldehydes than ketones due to reduced steric hindrance at the carbonyl carbon in aldehydes. For example, undergoes nearly quantitative hydration with an Khyd>1000K_\mathrm{hyd} > 1000 at 25°C, while forms a partial hydrate (Khyd≈1K_\mathrm{hyd} \approx 1), and acetone shows negligible hydration (Khyd<0.001K_\mathrm{hyd} < 0.001).

Alternative Synthetic Routes

Geminal diols can be prepared through the reduction of carboxylic acid derivatives using hydride reducing agents. For instance, ethyl trifluoroacetate is reduced with in a suitable solvent to yield trifluoroacetaldehyde hydrate (CF₃CH(OH)₂) directly, as the gem-diol form is stable under the reaction conditions. This method avoids over-reduction to the alcohol and is particularly useful for electron-deficient carbonyl equivalents where the hydrate predominates in equilibrium. Stronger reducing agents like lithium aluminum hydride (LiAlH₄) can also be employed on amides or acids, generating the gem-diol as a transient intermediate prior to further reduction to primary alcohols, though isolation requires controlled conditions for stable examples. Another established route involves the hydrolysis of halogenated precursors, such as geminal dihalides or related halogenoalkanes, particularly under aqueous conditions. A classic example is the preparation of chloral hydrate (CCl₃CH(OH)₂) by chlorination of ethanol in the presence of water and light, which proceeds through intermediate chlorinated species like trichloroacetaldehyde derivatives, ultimately yielding the stable gem-diol upon hydrolysis (CH₃CH₂OH + 4Cl₂ + H₂O → CCl₃CH(OH)₂ + 5HCl). This process is favored for polyhalogenated systems where the electron-withdrawing groups stabilize the diol against dehydration. Biocatalytic and metal-catalyzed approaches offer selective alternatives, especially in aqueous media for activated substrates. The hydration of pyruvic acid (CH₃COCOOH) to 2,2-dihydroxypropanoic acid (CH₃C(OH)₂COOH) is catalyzed by divalent metal ions such as Cu²⁺, Zn²⁺, or Ni²⁺, which mimic enzymatic active sites and shift the equilibrium toward the gem-diol with rate enhancements up to 10⁵-fold compared to uncatalyzed reactions. Enzymes like or synthetic metalloenzyme analogs employ similar zinc-based coordination to facilitate hydration, enabling mild, regioselective formation in biological or green synthesis contexts. Recent advancements include low-temperature processing of simple precursors for unstable gem-diols. Methanediol (CH₂(OH)₂), the simplest geminal diol, has been synthesized by electron irradiation of methanol-oxygen ices at 5 K, followed by thermal sublimation and spectroscopic identification in the gas phase, providing a model for interstellar or cryogenic routes applicable to other elusive hydrates.

Reactions and Stability

Equilibrium with Carbonyl Compounds

Geminal diols exist in reversible equilibrium with their corresponding carbonyl compounds through the hydration-dehydration process, where water adds across the C=O bond to form the tetrahedral gem-diol structure. The hydration equilibrium constant, defined as Khyd=[gem-diol][carbonyl][H2O]K_{\text{hyd}} = \frac{[\text{gem-diol}]}{[\text{carbonyl}][\text{H}_2\text{O}]}, quantifies this balance and varies significantly depending on the substrate. For most aldehydes and ketones, KhydK_{\text{hyd}} is small (typically < 1 M−1^{-1}), favoring the carbonyl form, but it increases markedly for electron-deficient carbonyls due to stabilization of the diol by electron-withdrawing groups that reduce the electrophilicity of the carbonyl carbon less severely in the hydrated state. For example, formaldehyde exhibits a high Khyd≈54K_{\text{hyd}} \approx 54 M−1^{-1} at 298 K, resulting in nearly complete hydration (>99%) in , while acetone has a much lower Khyd≈3.6×10−5K_{\text{hyd}} \approx 3.6 \times 10^{-5} M−1^{-1}, yielding less than 0.2% diol at equilibrium. Electron-deficient cases like trichloroacetaldehyde () show even larger values, with the apparent equilibrium constant Kapp=Khyd×[H2O]≈105K_{\text{app}} = K_{\text{hyd}} \times [\text{H}_2\text{O}] \approx 10^5 to 10610^6, allowing isolation of as a stable solid. According to , the position of this equilibrium can be shifted by altering water concentration: excess water drives the reaction toward the gem-diol, while removal of water—such as through , azeotropic removal, or drying agents—favors to the carbonyl compound. This reversibility is exploited in synthetic chemistry to generate or regenerate carbonyls from s under controlled conditions. For instance, in aqueous media, increasing enhances diol formation, but in non-aqueous environments, the equilibrium overwhelmingly favors the dehydrated form./Aldehydes_and_Ketones/Reactivity_of_Aldehydes_and_Ketones/Addition_of_Water_to_form_Hydrates_(Gem-Diols)) The kinetics of the hydration-dehydration process involve a common tetrahedral intermediate, where nucleophilic attack by on the protonated carbonyl leads to the gem-diol, and the reverse pathway protonates one hydroxyl group before elimination of . Acid catalysis accelerates both steps by protonating the carbonyl oxygen (for hydration) or a hydroxyl oxygen (for ), but is generally faster than hydration for substrates where the equilibrium favors the carbonyl, as reflected in the rate constants. For aliphatic aldehydes, the acid-catalyzed hydration rate constant kHk_{\text{H}} is on the order of 450 dm³ mol⁻¹ s⁻¹, while rates are higher, ensuring rapid equilibration. An energy diagram for this process typically shows the tetrahedral intermediate as a high-energy species, with the activation barrier for lowered under acidic conditions due to facilitated proton transfer involving molecules. Base catalysis is less common but can occur via steps, though acid-catalyzed pathways predominate for most carbonyls. The unfavorable Khyd<1K_{\text{hyd}} < 1 M⁻¹ for most simple carbonyls poses significant challenges to isolating gem-diols, as they spontaneously dehydrate even in moist air, reverting to the more stable carbonyl. Only stabilized examples, such as (from trichloroacetaldehyde) or hydrates of hexafluoroacetone, can be isolated due to their large KhydK_{\text{hyd}} values driven by electron-withdrawing substituents that destabilize the planar carbonyl relative to the tetrahedral diol. Attempts to isolate others often require conditions or low temperatures, but reversion occurs upon exposure to water removal techniques. Equilibrium mixtures are commonly monitored in situ using spectroscopic methods, with nuclear magnetic resonance (NMR) spectroscopy providing direct quantification of diol and carbonyl populations through distinct chemical shifts for the hydrated and free forms. For example, ¹H NMR in D₂O reveals the gem-diol protons of hydrated aldehydes as separate signals from the aldehydic proton. Infrared (IR) spectroscopy complements this by detecting the absence of the strong C=O stretch (~1700 cm⁻¹) in favor of O-H stretches (~3400 cm⁻¹) in diol-dominant mixtures, allowing real-time observation of the dynamic equilibrium.

Other Chemical Transformations

Geminal diols undergo oxidation to carboxylic acids, often proceeding through the hydrated form of the parent carbonyl compound. For instance, (the geminal diol of ) is oxidized to by hydroxyl radicals in aqueous solution, with identified as the primary product and minimal formation. In atmospheric conditions, this oxidation of hydrated in droplets serves as a major source of , enhancing atmospheric acidity via multiphase chemistry involving Criegee intermediates. Enzymatic oxidations, such as those catalyzed by aryl-alcohol , also proceed via gem-diol intermediates to yield carboxylic acids from aldehydes. Mild oxidants like similarly convert aldehydes—and their gem-diol forms—to carboxylic acids, as the hydration does not alter the overall reactivity at the carbon center. In , geminal diols act as reactive intermediates, particularly in oxidation processes where they enable efficient oxygen transfer from water or oxidants to the substrate. For example, in modern catalytic oxidations, in situ-formed gem-diols facilitate the conversion of alcohols to carbonyls or acids by serving as transient species that coordinate with metal catalysts. This role allows gem-diols to function as masked carbonyl equivalents in multi-step sequences, avoiding direct handling of reactive s while enabling selective transformations. Although gem-diols themselves are rarely isolated as stable protecting groups due to their equilibrium with carbonyls, stabilized variants (e.g., from electron-withdrawing substituents) can temporarily mask reactivity in synthetic routes. In , contributes to formation through heterogeneous reactions, such as acid-catalyzed with other carbonyls on surfaces, leading to secondary organic growth. Additionally, it participates in radical reactions, including OH-initiated oxidation chains that propagate particle and influence processing. These processes highlight the gem-diol's role in bridging gas-phase and aqueous-phase atmospheric transformations.

Examples and Applications

Notable Compounds

One prominent example of a geminal diol is , also known as hydrate, with the structure \ceH2C(OH)2\ce{H2C(OH)2}. It represents the simplest geminal diol and predominates in aqueous solutions of , where the equilibrium strongly favors the hydrated form due to the high hydration constant (approximately 2000–3000), resulting in over 99% conversion to the diol in dilute solutions. This compound is integral to commercial solutions, such as formalin, which are primarily composed of in water. Chloral hydrate, or 2,2,2-trichloroethane-1,1-diol (\ceCl3CCH(OH)2\ce{Cl3CCH(OH)2}), is a notable stable that can be isolated as a colorless crystalline solid with a of 57–58 °C. Its enhanced stability arises from the electron-withdrawing trichloromethyl group, which shifts the hydration equilibrium toward the diol form and prevents facile . Historically used as a and in , it exemplifies how substituents can confer isolable stability to geminal diols. Acetaldehyde hydrate, known as 1,1-ethanediol (\ceCH3CH(OH)2\ce{CH3CH(OH)2}), exists in aqueous solution in a roughly 50:50 equilibrium with its carbonyl precursor, reflecting a hydration equilibrium constant of approximately 1. This partial hydration yields a colorless liquid mixture that is not readily isolable as the pure diol. Hexafluoroacetone hydrate, or 1,1,1,3,3,3-hexafluoropropane-2,2-diol (\ce(CF3)2C(OH)2\ce{(CF3)2C(OH)2}), is a highly stable geminal diol due to the strong electron-withdrawing effects of the six fluorine atoms, which promote hydration with an equilibrium constant of approximately 2×1042 \times 10^4 M−1^{-1}. It forms a crystalline solid that resists dehydration under ambient conditions. In biological contexts, certain sialic acid derivatives, such as those in glycoproteins, feature gem-diol moieties in their open-chain forms, where the ketone at C2 hydrates under specific conditions (e.g., low pH), contributing to conformational flexibility and interactions in glycan structures.

Biological and Industrial Uses

Geminal diols function as transient intermediates in biological metabolism, particularly in detoxification pathways. For instance, the hydrated form of glyoxal participates in the glutathione-dependent glyoxalase system, where it reacts non-enzymatically with glutathione to form a hemithioacetal intermediate, facilitating the conversion to glycolic acid and mitigating oxidative stress. This pathway is crucial in cells exposed to reactive carbonyl species, preventing protein and DNA damage. Additionally, formaldehyde, largely existing as its geminal diol (methanediol) in aqueous cellular environments, serves as a key intermediate in one-carbon metabolism and is rapidly detoxified by enzymes like formaldehyde dehydrogenase in humans and methylotrophic bacteria. In enzymatic contexts, diols appear as short-lived intermediates in hydration reactions at active sites, such as in the selective steps of certain hydrolases, where the diol form enables precise control over carbonyl regeneration. , a stable diol derived from , has been employed medicinally as a and since the 1870s, primarily for short-term treatment and to induce or allay anxiety post-operatively. It is particularly noted for pediatric during diagnostic procedures like or dental work, administered orally at doses of 50–100 mg/kg, though its use has declined due to safer alternatives. Recent studies as of 2024 confirm its efficacy in severe within two weeks, while ongoing research highlights potential impacts on development in pediatric use. In drug design, geminal diols and their ester derivatives (acylals) are investigated as prodrugs for carbonyl compounds, enhancing aqueous solubility and enabling controlled release in physiological conditions. Industrially, formaldehyde hydrate (formalin, a 37–50% aqueous solution where over 99% exists as the geminal diol) is a cornerstone for synthesizing resins and polymers, including urea-formaldehyde and phenol-formaldehyde types used in adhesives for particleboard, plywood, and coatings, accounting for over 50% of global formaldehyde consumption. In the textile sector, these hydrated formaldehyde solutions react with cellulose to form N-methylol compounds, which cross-link fibers in durable-press finishes, providing crease resistance and shrinkage control to cotton fabrics while maintaining breathability. Environmentally, methanediol plays a pivotal role in atmospheric aqueous-phase chemistry, forming in cloud droplets from formaldehyde hydration and undergoing OH radical oxidation to yield formic acid, which contributes to secondary organic aerosol growth and influences cloud albedo and pollutant degradation pathways like those of volatile organic compounds. Emerging applications leverage geminal diols in , particularly through biocatalytic processes using renewable feedstocks. For example, the geminal diol of (Cyrene, derived from ) acts as a tunable in aqueous mixtures, enhancing of poorly water-soluble substrates by up to 100-fold for biocatalyzed reactions like hydrolyses, while remaining non-mutagenic and recyclable, thus supporting sustainable systems for pharmaceutical synthesis.

References

  1. http://www.chem.ucla.edu/~harding/IGOC/G/geminal.html
  2. https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Supplemental_Modules_%28Organic_Chemistry%29/Aldehydes_and_Ketones/Reactivity_of_Aldehydes_and_Ketones/Addition_of_Water_to_form_Hydrates_%28Gem-Diols%29
  3. https://www2.chemistry.msu.edu/faculty/reusch/virttxtjml/aldket1.htm
  4. https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Map%253A_Organic_Chemistry_%28Wade%29_Complete_and_Semesters_I_and_II/Map%253A_Organic_Chemistry_%28Wade%29/03%253A_Functional_Groups_and_Nomenclature/3.08%253A_3.8_Alcohols_-__Classification_and_Nomenclature
  5. https://pmc.ncbi.nlm.nih.gov/articles/PMC8740743/
  6. https://doi.org/10.1073/pnas.2111938119
  7. https://www.ch.ic.ac.uk/local/organic/tutorial/DB_Carbonylnotes1.pdf
  8. https://pubs.acs.org/doi/10.1021/jacs.4c02637
  9. https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Organic_Chemistry_%28Morsch_et_al.%29/19%253A_Aldehydes_and_Ketones-_Nucleophilic_Addition_Reactions/19.05%253A_Nucleophilic_Addition_of_Water-_Hydration
  10. https://www.masterorganicchemistry.com/2010/05/28/acetals-hemiacetals-hydrates/
  11. https://chemistry.stackexchange.com/questions/94417/why-does-formaldehyde-exist-primarily-as-the-gem-diol-in-aqueous-solution
  12. https://www.ebsco.com/research-starters/chemistry/diols
  13. https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Organic_Chemistry_%28Morsch_et_al.%29/17%253A_Alcohols_and_Phenols/17.11%253A_Spectroscopy_of_Alcohols_and_Phenols
  14. https://www.researchgate.net/publication/269933546_Structural_and_Spectroscopic_Properties_of_Methanediol_in_Aqueous_Solutions_from_Quantum_Chemistry_Calculations_and_Ab_Initio_Molecular_Dynamics_Simulations
  15. https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Supplemental_Modules_%28Organic_Chemistry%29/Alcohols/Properties_of_Alcohols/Acidities_of_Alcohols
  16. https://www.researchgate.net/publication/244757774_Influence_of_Ionic_Strength_and_Cation_Nature_on_the_Deprotonation_of_Methanediol_in_Alkaline_Solution
  17. https://chemistry.stackexchange.com/questions/107616/how-can-benzaldehyde-have-a-pka-of-14-9
  18. https://openstax.org/books/organic-chemistry/pages/19-5-nucleophilic-addition-of-h2o-hydration
  19. https://www.chemistrysteps.com/reactions-of-aldehydes-and-ketones-with-water/
  20. https://www2.oberlin.edu/faculty/mjelrod/elrod2021carbonylhydration.pdf
  21. https://onlinelibrary.wiley.com/doi/10.1002/047084289X.rn01730
  22. https://patents.google.com/patent/US2478152A/en
  23. https://www.pnas.org/doi/10.1073/pnas.2111938119
  24. https://onlinelibrary.wiley.com/doi/abs/10.1002/bbpc.19800840109
  25. https://pure.rug.nl/ws/files/3619450/2002ChemEngSciWinkelman.pdf
  26. https://pubchem.ncbi.nlm.nih.gov/compound/Chloral
  27. https://onlinelibrary.wiley.com/doi/abs/10.1002/bbpc.19820860208
  28. https://pubs.acs.org/doi/10.1021/ja00120a005
  29. https://www.researchgate.net/publication/257862148_Spontaneous_hydration_of_the_carbonyl_group_in_substituted_propynals_in_aqueous_medium
  30. https://ri.conicet.gov.ar/bitstream/handle/11336/47661/CONICET_Digital_Nro.a59b06c8-1be0-4db0-91f6-b7f317b05887_A.pdf?sequence=2&isAllowed=y
  31. https://pubs.rsc.org/en/content/articlelanding/1991/ft/ft9918701513
  32. https://pmc.ncbi.nlm.nih.gov/articles/PMC8116209/
  33. https://search.lib.uconn.edu/view/action/uresolver.do?operation=resolveService&package_service_id=43836219930002432&institutionId=2432&customerId=2430&VE=true
  34. https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/ejoc.202500346
  35. https://pubs.rsc.org/en/content/getauthorversionpdf/c5ob00238a
  36. https://pmc.ncbi.nlm.nih.gov/articles/PMC8833171/
  37. https://pubchem.ncbi.nlm.nih.gov/compound/Methanediol
  38. https://pubchem.ncbi.nlm.nih.gov/compound/Chloral-Hydrate
  39. https://www.chemicalbook.com/ChemicalProductProperty_EN_CB0198709.htm
  40. https://www.sciencedirect.com/topics/chemistry/equilibrium-constant
  41. https://pubs.rsc.org/en/content/articlepdf/1950/tf/tf9504600034
  42. https://pubchem.ncbi.nlm.nih.gov/compound/69617
  43. https://www.chegg.com/homework-help/questions-and-answers/1-equilibrium-constant-khyde-hydration-hexafluoroacetone-22-x-104-translates-almost-comple-q39111929
  44. https://www.researchgate.net/publication/22280845_Sialic_acid_A_Calcium-binding_carbohydrate
  45. https://patents.google.com/patent/WO2015123756A1/en
  46. https://ec.europa.eu/health/ph_risk/committees/04_sccp/docs/sccp_o_023.pdf
  47. https://pmc.ncbi.nlm.nih.gov/articles/PMC8184665/
  48. https://www.mdpi.com/2076-2607/10/2/220
  49. https://www.sciencedirect.com/topics/chemistry/1-1-diol
  50. https://www.ncbi.nlm.nih.gov/books/NBK294283/
  51. https://pmc.ncbi.nlm.nih.gov/articles/PMC6679948/
  52. https://pharmanovia.com/news/new-pharmanovia-study-results-reveal-chloral-hydrate-noticeably-improves-severe-insomnia-within-two-weeks/
  53. https://www.dovepress.com/chloral-hydrates-impact-on-brain-development-from-clinical-safety-to-m-peer-reviewed-fulltext-article-DDDT
  54. https://www.sciencedirect.com/topics/engineering/formaldehyde-resin
  55. https://www.cottoninc.com/wp-content/uploads/2017/12/TRI-4008-Formaldehyde-in-Textiles.pdf
  56. https://www.nature.com/articles/s41586-021-03462-x
  57. https://pubs.acs.org/doi/10.1021/acssuschemeng.9b00470
Add your contribution
Related Hubs
User Avatar
No comments yet.