Selenium Oxides

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  • Identifiers

    CAS number
    7446-08-4

    Molecular formula
    O2Se

    SMILES
    O=[Se]=O

    Safety labels

    Corrosive
    Corrosive

    Acute Toxic
    Acute Toxic

    Health Hazard
    Health

    Environmental Hazard
    Environmental

  • Odor profile

    Fragrance
    Odorless 90.88%
    Sour 24.62%
    Sharp 24.37%
    Burnt 23.44%
    Pungent 20.02%
    Caramellic 17.44%
    Bitter 13.93%
    Clean 11.65%
    Ethereal 11.65%
    Aromatic 9.85%

     

    Odor threshold

    • 0.0002 mg/cu m
    • Air: 2.0 ppm

  • Properties

    pKa est.
    -2.13 (strong acid)

    Molecular weight
    110.97 g/mol

    Melting point expt.

    • 340 °C under pressure

    Boiling point

    • 599 °F at 760 mmHg (sublimes) (USCG, 1999)

    Flash point

    • 41.0 ˚C est.

    Solubility expt.

    • Soluble in concentrated sulfuric acid
    • Solubility (parts/100 parts solvent): 10.16 in methanol at 11.8 °C; 6.67 in 93% ethanol at 14 °C; 4.35 in acetone at 15.3 °C; 1.11 in acetic acid at 13.9 °C
    • In water, 400 g/L at 20 °C
    • 264 g/100 g water at 22 °C
    • For more Solubility (Complete) data for SELENIUM DIOXIDE (6 total), please visit the HSDB record page.
    • Solubility in water, g/100ml at 20 °C: 40

  • Synonyms

    • SELENIUM DIOXIDE
    • Selenium(IV) oxide
    • 7446-08-4
    • Selenium oxide
    • Selenious anhydride
    • Oxoselane oxide
    • Selenium dioxide dimer
    • Selenous acid anhydride
    • Selenium oxide (SeO2)
    • Selenium(IV) dioxide (1:2)
    • Selenium oxide (Se2O4)
    • RCRA waste number U204
    • Selenium oxide (1:2)
    • CCRIS 5820
    • HSDB 677
    • 9N3UK29E57
    • EINECS 231-194-7
    • MFCD00003562
    • NSC 56753
    • NSC-56753
    • SELENIUM (IV) OXIDE
    • SELENIUM DIOXIDE [HSDB]
    • 12640-89-0
    • DTXSID4021264
    • Seleniumdioxide
    • EC 231-194-7
    • Selenous anhydride
    • Selenium(IV) dioxide
    • Selenonyl
    • seleninyl oxygen
    • dioxido de selenio
    • Oxoselane oxide #
    • biossido di selenio
    • dioxyde de selenium
    • EINECS 235-738-4
    • SeO2
    • Selenium oxide, SeO2
    • selenium (IV) dioxide
    • SELENIUM OXIDE [MI]
    • WLN: SE O2
    • UNII-9N3UK29E57
    • DTXCID901264
    • CHEMBL3183452
    • SELENIUM OXIDE [WHO-DD]
    • (oxo-lambda4-selanylidene)oxidane
    • Selenium dioxide, puriss., 98%
    • NSC56753
    • Tox21_202597
    • NA2811
    • STL264213
    • AKOS015855284
    • FS34840
    • Selenium oxide [NA2811] [Poison]
    • Selenium(IV) oxide (99.999%-Se)
    • NCGC00260145-01
    • BP-21360
    • CAS-7446-08-4
    • DB-004088
    • E1459
    • NS00113742
    • Selenium dioxide, reagent grade, powder, 98%
    • Selenium dioxide, >=99.9% trace metals basis
    • Selenium dioxide, 99.999% trace metals basis
    • A838139
    • Q411386
    • Selenium dioxide, ReagentPlus(R), powder, 99.8% trace metals basis
    • 231-194-7

  • Applications

    Selenium Oxides (CAS 7446-08-4) are primarily used as oxidizing agents in organic synthesis, notably for allylic oxidation that converts allylic C–H bonds into aldehyde or ketone functionalities and provides intermediates for the production of fine chemicals. They are commonly employed in the synthesis of pharmaceutical intermediates and specialty chemicals, enabling selective oxidation steps in complex routes. In fragrance and flavor chemistry, allylic oxidation products derived from Selenium Oxides can serve as aroma precursors or intermediates for further derivatization. In polymer and materials chemistry, the reagent can be used to functionalize allylic sites on polymers, introducing carbonyl groups for subsequent processing or crosslinking. Activities are conducted under controlled conditions and subject to local regulations.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 238.94
    methanol 299.49
    isopropanol 227.84
    water 41.68
    ethyl acetate 164.45
    n-propanol 172.7
    acetone 417.11
    n-butanol 159.04
    acetonitrile 238.96
    DMF 1173.44
    toluene 105.91
    isobutanol 128.07
    1,4-dioxane 341.69
    methyl acetate 196.54
    THF 530.28
    2-butanone 228.19
    n-pentanol 117.53
    sec-butanol 172.82
    n-hexane 51.51
    ethylene glycol 154.53
    NMP 674.9
    cyclohexane 68.89
    DMSO 1055.92
    n-butyl acetate 95.09
    n-octanol 105.18
    chloroform 238.77
    n-propyl acetate 107.09
    acetic acid 227.98
    dichloromethane 259.48
    cyclohexanone 212.2
    propylene glycol 125.03
    isopropyl acetate 125.93
    DMAc 775.79
    2-ethoxyethanol 224.45
    isopentanol 131.47
    n-heptane 46.1
    ethyl formate 144.27
    1,2-dichloroethane 225.69
    n-hexanol 108.76
    2-methoxyethanol 440.39
    isobutyl acetate 67.29
    tetrachloromethane 91.52
    n-pentyl acetate 100.8
    transcutol 313.62
    n-heptanol 91.07
    ethylbenzene 62.52
    MIBK 139.95
    2-propoxyethanol 213.22
    tert-butanol 289.03
    MTBE 228.23
    2-butoxyethanol 157.83
    propionic acid 140.2
    o-xylene 97.97
    formic acid 169.23
    diethyl ether 251.36
    m-xylene 93.67
    p-xylene 76.32
    chlorobenzene 107.17
    dimethyl carbonate 170.06
    n-octane 29.59
    formamide 279.06
    cyclopentanone 324.39
    2-pentanone 207.48
    anisole 145.92
    cyclopentyl methyl ether 240.81
    gamma-butyrolactone 313.22
    1-methoxy-2-propanol 352.72
    pyridine 238.2
    3-pentanone 177.73
    furfural 329.85
    n-dodecane 26.77
    diethylene glycol 225.18
    diisopropyl ether 107.39
    tert-amyl alcohol 210.05
    acetylacetone 238.71
    n-hexadecane 28.93
    acetophenone 132.0
    methyl propionate 191.24
    isopentyl acetate 84.2
    trichloroethylene 256.28
    n-nonanol 95.23
    cyclohexanol 158.41
    benzyl alcohol 110.65
    2-ethylhexanol 74.31
    isooctanol 74.76
    dipropyl ether 124.82
    1,2-dichlorobenzene 109.21
    ethyl lactate 87.5
    propylene carbonate 153.95
    n-methylformamide 359.78
    2-pentanol 147.36
    n-pentane 73.64
    1-propoxy-2-propanol 165.24
    1-methoxy-2-propyl acetate 126.17
    2-(2-methoxypropoxy) propanol 147.38
    mesitylene 78.69
    ε-caprolactone 169.8
    p-cymene 55.04
    epichlorohydrin 313.7
    1,1,1-trichloroethane 193.4
    2-aminoethanol 166.15
    morpholine-4-carbaldehyde 492.4
    sulfolane 494.97
    2,2,4-trimethylpentane 35.07
    2-methyltetrahydrofuran 293.79
    n-hexyl acetate 119.5
    isooctane 32.01
    2-(2-butoxyethoxy)ethanol 184.74
    sec-butyl acetate 76.01
    tert-butyl acetate 156.82
    decalin 33.54
    glycerin 204.87
    diglyme 306.74
    acrylic acid 148.63
    isopropyl myristate 74.47
    n-butyric acid 148.74
    acetyl acetate 113.1
    di(2-ethylhexyl) phthalate 69.35
    ethyl propionate 110.27
    nitromethane 398.73
    1,2-diethoxyethane 153.15
    benzonitrile 113.92
    trioctyl phosphate 60.72
    1-bromopropane 150.9
    gamma-valerolactone 346.45
    n-decanol 79.12
    triethyl phosphate 68.76
    4-methyl-2-pentanol 94.23
    propionitrile 151.59
    vinylene carbonate 139.53
    1,1,2-trichlorotrifluoroethane 257.48
    DMS 109.64
    cumene 52.28
    2-octanol 82.91
    2-hexanone 121.31
    octyl acetate 90.55
    limonene 80.7
    1,2-dimethoxyethane 379.21
    ethyl orthosilicate 70.46
    tributyl phosphate 63.71
    diacetone alcohol 206.07
    N,N-dimethylaniline 149.53
    acrylonitrile 197.72
    aniline 140.72
    1,3-propanediol 195.96
    bromobenzene 106.54
    dibromomethane 203.91
    1,1,2,2-tetrachloroethane 249.71
    2-methyl-cyclohexyl acetate 79.33
    tetrabutyl urea 104.2
    diisobutyl methanol 68.38
    2-phenylethanol 98.52
    styrene 80.94
    dioctyl adipate 93.95
    dimethyl sulfate 318.97
    ethyl butyrate 88.7
    methyl lactate 158.53
    butyl lactate 90.09
    diethyl carbonate 67.25
    propanediol butyl ether 142.84
    triethyl orthoformate 81.76
    p-tert-butyltoluene 62.3
    methyl 4-tert-butylbenzoate 149.46
    morpholine 365.79
    tert-butylamine 203.34
    n-dodecanol 68.46
    dimethoxymethane 567.55
    ethylene carbonate 119.23
    cyrene 149.06
    2-ethoxyethyl acetate 122.01
    2-ethylhexyl acetate 72.8
    1,2,4-trichlorobenzene 129.25
    4-methylpyridine 224.22
    dibutyl ether 104.15
    2,6-dimethyl-4-heptanol 68.38
    DEF 328.77
    dimethyl isosorbide 219.22
    tetrachloroethylene 189.6
    eugenol 149.12
    triacetin 120.47
    span 80 138.52
    1,4-butanediol 99.75
    1,1-dichloroethane 195.81
    2-methyl-1-pentanol 95.56
    methyl formate 282.51
    2-methyl-1-butanol 120.43
    n-decane 36.03
    butyronitrile 142.43
    3,7-dimethyl-1-octanol 85.4
    1-chlorooctane 73.93
    1-chlorotetradecane 46.36
    n-nonane 35.67
    undecane 30.39
    tert-butylcyclohexane 32.67
    cyclooctane 34.89
    cyclopentanol 198.32
    tetrahydropyran 251.48
    tert-amyl methyl ether 192.76
    2,5,8-trioxanonane 253.11
    1-hexene 88.02
    2-isopropoxyethanol 167.39
    2,2,2-trifluoroethanol 137.95
    methyl butyrate 131.59

    Scent© AI

1 4

IFRA standard 51

Recommendation
No restriction
Maximum acceptable concentrations in the finished product (%)
Category 1
Products applied to the lips
 No restriction Category 7A
Rinse-off products applied to the hair with some hand contact
 No restriction
Category 2
Products applied to the axillae
 No restriction Category 7B
Leave-on products applied to the hair with some hand contact
 No restriction
Category 3
Products applied to the face/body using fingertips
 No restriction Category 8
Products with significant anogenital exposure
 No restriction
Category 4
Products related to fine fragrance
 No restriction Category 9
Products with body and hand exposure, primarily rinse off
 No restriction
Category 5A
Body lotion products applied to the body using the hands (palms), primarily leave on
 No restriction Category 10A
Household care products with mostly hand contact
 No restriction
Category 5B
Face moisturizer products applied to the face using the hands (palms), primarily leave on
 No restriction Category 10B
Household care products with mostly hand contact, including aerosol/spray products (with potential leave-on skin contact)
 No restriction
Category 5C
Hand cream products applied to the hands using the hands (palms), primarily leave on
 No restriction Category 11A
Products with intended skin contact but minimal transfer of fragrance to skin from inert substrate without UV exposure
 No restriction
Category 5D
Baby Creams, baby Oils and baby talc
 No restriction Category 11B
Products with intended skin contact but minimal transfer of fragrance to skin from inert substrate with potential UV exposure
 No restriction
Category 6
Products with oral and lip exposure
 No restriction Category 12
Products not intended for direct skin contact, minimal or insignificant transfer to skin
 No restriction