2516-92-9

Usage

Uses

Used in Plastics Industry:
Bis(2,2,6,6-tetramethyl-1-piperidinyloxy-4-yl) sebacate is used as a stabilizer for plastics to protect them from degradation caused by UV radiation and thermal oxidation, thereby extending their service life and maintaining their physical properties.
Used in Rubber Industry:
In the rubber industry, Bis(2,2,6,6-tetramethyl-1-piperidinyloxy-4-yl) sebacate is used as a stabilizer to prevent the degradation of rubber materials, ensuring their durability and resistance to environmental factors.
Used in Adhesives:
Bis(2,2,6,6-tetramethyl-1-piperidinyloxy-4-yl) sebacate is used as a stabilizer in adhesives to enhance their resistance to UV radiation and thermal oxidation, thus improving their bonding performance and longevity.
Used in Coatings:
Bis(2,2,6,6-tetramethyl-1-piperidinyloxy-4-yl) sebacate is used as a stabilizer in coatings to protect the coated surfaces from degradation due to UV radiation and thermal oxidation, ensuring the coatings' durability and appearance retention.
Used in Food Packaging:
Bis(2,2,6,6-tetramethyl-1-piperidinyloxy-4-yl) sebacate is used as a stabilizer in food packaging materials to ensure the safety and integrity of the packaging, protecting the food from environmental factors that could cause spoilage.
Used in Agricultural Applications:
In agricultural applications, Bis(2,2,6,6-tetramethyl-1-piperidinyloxy-4-yl) sebacate is used as a stabilizer for materials used in farming equipment and structures, protecting them from degradation and extending their service life, thus contributing to sustainable agricultural practices.

InChI:InChI=1/C19H35NO6/c1-18(2)12-14(21)13-19(3,4)20(18)26-15(17(24)25)10-8-6-5-7-9-11-16(22)23/h14-15,21H,5-13H2,1-4H3,(H,22,23)(H,24,25)/p-2

Synthetic route

bis-(2,2,6,6-tetramethyl-4-piperidinyl) sebacate (52829-07-9) → bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9)

Conditions	Yield
With sodium tungstate; dihydrogen peroxide; edetate disodium In methanol; acetonitrile	10%

bis-(2,2,6,6-tetramethyl-4-piperidinyl) sebacate (52829-07-9) → bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9) + C28H51N2O5 (80004-15-5)

Conditions	Yield
With 3-chloro-benzenecarboperoxoic acid In dichloromethane 1) 273 K, 1 h, 2) 1 h, reflux;

TEMPOL (45985-24-8, 2226-96-2) + sebacic acid mono methyl ester (818-88-2) → bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9)

Conditions	Yield
With sodium methylate In n-heptane Heating / reflux;

sebacoyl chloride (111-19-3) + TEMPOL (45985-24-8, 2226-96-2) → bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9)

Conditions	Yield
With dmap; triethylamine In dichloromethane at 0 - 20℃; for 18h;

bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9) + octane (111-65-9) → bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate

Conditions	Yield
With dihydrogen peroxide at 75 - 80℃; for 9h; Reagent/catalyst; Temperature;	89.7%
With iron(III) chloride; dihydrogen peroxide; acetic acid In water; acetonitrile at 76℃; for 4h; Heating / reflux;	31%

bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9) → di(1-phenoxy-2,2,6,6-tetramethyl-piperidin-4-yl) sebacate (371756-16-0)

Conditions	Yield
With pyridine; tert.-butylnitrite; aniline In n-heptane; ethyl acetate	47.9%

bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9) + cyclohexane (110-82-7) → bis(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl) sebacate

Conditions	Yield
With methanesulfonic acid; dihydrogen peroxide; iron(II) sulfate In water; acetonitrile at 55℃; for 5.5h; Heating / reflux;	43%

bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9) → bis-(2,2,6,6-tetramethyl-4-piperidinyl) sebacate (52829-07-9)

Conditions	Yield
With ethanethiol In benzene	17%

styrene (292638-84-7) + bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9) → polymer, Mn (g/mol) = 20600, Mw/Mn = 1.68; monomer(s): styrene; decanedioic acid bis(1-oxy-2,2,6,6-tetramethylpiperidin-4-yl) ester

Conditions	Yield
With dibenzoyl peroxide at 130℃; for 2.5h;	53 % Turnov.

styrene (292638-84-7) + bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9) → polymer, Mn (g/mol) = 25000, Mw/Mn = 1.72; monomer(s): styrene; decanedioic acid bis(1-oxy-2,2,6,6-tetramethylpiperidin-4-yl) ester

Conditions	Yield
With dibenzoyl peroxide at 130℃; for 14h;	86 % Turnov.

styrene (292638-84-7) + bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9) → polymer, Mn (g/mol) = 26300, Mw/Mn = 1.60; monomer(s): styrene; decanedioic acid bis(1-oxy-2,2,6,6-tetramethylpiperidin-4-yl) ester

Conditions	Yield
With dibenzoyl peroxide at 130℃; for 5h;	76 % Turnov.

nonan-1-al (124-19-6) + bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9) → bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate

Conditions	Yield
With dihydrogen peroxide; acetic acid; calcium chloride; copper dichloride In water; toluene at 20 - 40℃; for 11h; Product distribution / selectivity;
With dihydrogen peroxide; acetic acid; copper dichloride In water; toluene; tert-butyl alcohol at 25 - 40℃; for 12h; Product distribution / selectivity;

bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9) + n-heptane (142-82-5) → bis(1-heptyloxy-2,2,6,6-tetramethylpiperidin-4-yl) sebacate

Conditions	Yield
With hydrogenchloride; iron(III) chloride; dihydrogen peroxide In water; acetonitrile at 33 - 68℃; for 6.5h;

bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9) + oct-1-ene (111-66-0) → C44H80N2O6 + C44H80N2O6 (865710-98-1)

Conditions	Yield
With tert.-butylhydroperoxide; copper(ll) bromide In water at 60℃; for 0.5h; Product distribution / selectivity;
With tert.-butylhydroperoxide; tetra-(n-butyl)ammonium iodide In water at 60℃; for 2.5 - 5.25h; Product distribution / selectivity;
With tert.-butylhydroperoxide; copper dichloride In water at 60℃; for 3h; Product distribution / selectivity;

bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9) + 1-bromo-3-propanol (627-18-9) → bis[1-(3-hydroxypropoxy)-2,2,6,6-tetramethylpiperidin-4-yl] Sebacate (1098596-25-8)

Conditions	Yield
With tri-n-butyl-tin hydride In chlorobenzene

bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9) + 12-bromododecanol (3344-77-2) → Bis[1-(12-hydroxy-1-dodecyloxy)-2,2,6,6-tetramethylpiperidin-4-yl] Sebacate (1098596-19-0)

Conditions	Yield
With tri-n-butyl-tin hydride In chlorobenzene

1-bromo-2-propanol (19686-73-8) + bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9) → bis[1-(2-hydroxypropoxy)-2,2,6,6-tetramethylpiperidin-4-yl] Sebacate (1098596-20-3)

Conditions	Yield
With tri-n-butyl-tin hydride In chlorobenzene

bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9) + boron trifluoride diethyl etherate (109-63-7) → 4,4'-[(1,10-dioxo-1,10-decanediyl)bis(oxy)]bis[2,2,6,6-tetramethyl-1-oxo-piperidinium] tetrafluoroborate

Conditions	Yield
Stage #1: boron trifluoride diethyl etherate With isopentyl nitrite In diethyl ether for 0.0833333h; Inert atmosphere; Stage #2: bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate In diethyl ether for 0.5h; Inert atmosphere;

bis(1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl)sebacate (2516-92-9) → 1,10-bis(1-hydroxy-2,2,6,6-tetramethyl-4-piperidinyl) decanedioate (30538-92-2)

Conditions	Yield
With ascorbic acid In 1,4-dioxane; water at 20℃; for 1h; Inert atmosphere;

Upstream product

• 52829-07-9 bis-(2,2,6,6-tetramethyl-4-piperidinyl) sebacate 
• 111-19-3 sebacoyl chloride 
• 45985-24-8 TEMPOL 
• 818-88-2 sebacic acid mono methyl ester 

Downstream Products

• 371756-16-0 di(1-phenoxy-2,2,6,6-tetramethyl-piperidin-4-yl) sebacate 
• 52829-07-9 bis-(2,2,6,6-tetramethyl-4-piperidinyl) sebacate 

Relevant academic research and scientific papers

Method for preparing hindered amine nitroxide free radical compound by alkaline heterogeneous catalysis system

The method comprises the following steps: dissolving a hindered amine compound in an organic solvent; adjusting pH by a carbonate aqueous solution; reacting with an aqueous hydrogen peroxide solution; and generating a hindered amine nitroxide free radical compound (IV). (V) Or (VI). The method is high in universality, and the hindered amine nitroxide free radical compound with various structures is prepared. The method is high in catalytic activity, short in reaction time, high in yield, simple in preparation process and convenient to operate; a high-purity target product can be obtained through simple phase separation, drying and concentration in the post-treatment process; meanwhile, the aqueous solution system and ethyl acetate can be recycled. Small by-products.

LIQUID-CRYSTALLINE MEDIUM, METHOD FOR THE STABILISATION THEREOF, AND LIQUID-CRYSTAL DISPLAY

Liquid crystalline medium comprises (a) at least one substituted piperidine derivative (I) excluding substituted carbonic acid dipiperidin-4-yl ester compounds (Ia), and (b) at least one substituted 1-cyclohexylmethoxy-2,3-difluoro-benzene derivative (II). Liquid crystalline medium comprises (a) at least one substituted piperidine derivative of formula (I) excluding substituted carbonic acid dipiperidin-4-yl ester compounds of formula (Ia), and (b) at least one substituted 1-cyclohexylmethoxy-2,3-difluoro-benzene derivative of formula (II). n : 1-4; m : 4-n; Z1 : organic group having 4 binding sites; Z11, Z12 : -O-, -(C=O)-, -(N-R14)- or single bond, where Z11 and Z12 do not simultaneously represent -O-; r, s : 0 or 1; either Y11-Y14 : 1-4C alkyl; or Y11+Y12, Y13+Y14 : 3-6C divalent group; R11 : O-R13, oxygen free radical or OH, preferably O-R13, preferably isopropyloxy, cyclohexyloxy, acetophenyl-oxy or benzyloxy, or oxygen free radical (preferred); R12 : H, F, OR14, NR14R15, 1-20C alkyl (in which 1 CH 2 group or several CH 2 groups are optionally replaced by -O- or -C(=O)-, where two adjacent CH 2 groups are not optionally replaced by -O-), hydrocarbyl, preferably cycloalkyl or alkyl-cycloalkyl (in which 1 CH 2 group or several CH 2 groups are optionally replaced by -O- or -C(=O)-, where 2 adjacent CH 2 groups are not optionally replaced by -O-, and 1 H or several H are optionally replaced by OR14, N(R14)(R15) or R16) or (hetero)aromatic hydrocarbyl (in which 1 H or several H are optionally replaced by OR14, N(R14)(R15) or R16); R13 : 1-20C alkyl (in which 1 CH 2 group or several CH 2 groups are optionally replaced by -O- or -C(=O)-, where two adjacent CH 2 groups are not optionally replaced by -O-), hydrocarbyl, preferably cycloalkyl or alkyl-cycloalkyl (in which 1 CH 2 group or several CH 2 groups are optionally replaced by -O- or -C(=O)-, where 2 adjacent CH 2 groups are not optionally replaced by -O-, and 1 H or several H are optionally replaced by OR14, N(R14)(R15) or R16), (hetero)aromatic hydrocarbyl (in which 1 H or several H are optionally replaced by OR14, N(R14)(R15) or R16), 1,4-cyclohexylene (in which at least one CH 2 group is optionally replaced by -O-, -CO- or -NR14-) or acetophenyl, isopropyl or 3-heptyl; R14, R15 : 1-10C alkyl, 1-10C acyl, aromatic 6-12C hydrocarbyl or 6-12C carboxylic acid; R16 : 1-10C alkyl (in which 1 CH 2 group or several CH 2 groups are optionally replaced by -O- or -C(=O)-, where 2 adjacent CH 2 groups are not optionally replaced by -O-); G : oxygen free radical; G1 : 1-4C alkyl; R41 : unsubstituted 1-7C alkenyl; R42 : 1-7C alkyl, 1-6C alkoxy or 2-6C alkenyloxy (all unsubstituted); and i : 0 or 1. Provided that when n is 1, R11 is oxygen free radical and -[Z11] r-[Z12] s is -O-, -(CO)-O-, -O-(CO)-, -O-(CO)-O-, -NR14- or -NR14-(CO)-, then [R12] m-Z1 is not 1-10C alkyl, cycloalkyl, cycloalkylalkyl or alkyl-cycloalkyl (in all groups at least one CH 2 group is optionally replaced by -O- such that two O atoms are not directly bonded with each other); and when n is 2 and R11 is O-R13, then R13 is not nitrogen-1-9C alkyl. Independent claims are also included for: (1) an electro-optical display or an electro-optical component comprising the above liquid crystalline medium; (2) preparing the liquid crystalline medium, comprising mixing (I) with (II), substituted bicyclohexyl compounds of formula (IVb) and/or substituted 1-cyclohexyl-2,3-difluorobenzene derivatives of formula (IIIa), substituted 1-cyclohex-1-enyl-2,3-difluorobenzene derivatives of formula (IIIb), substituted 2,3-difluoro-biphenyl derivatives of formula (IIIc) or substituted 2',3'-difluoro-[1,1';4',1'']terphenyl compounds of formula (IIId); and (3) stabilizing the liquid crystalline medium, comprising adding a medium which comprises (I) and optionally 2,6-di-tert-butyl-4-(4-propyl-cyclohexyl)-phenol, 2,6-di-tert-butyl-4-(5-propyl-[1,3]dioxan-2-yl)-phenol, 3,5-di-tert-butyl-4-hydroxy-benzoic acid hexadecyl ester, 3,5-di-tert-butyl-4-hydroxy-benzoic acid 4-pentyl-cyclohexylmethyl ester, 2,5-bis-(1,1,3,3-tetramethyl-butyl)-benzene-1,4-diol and acrylic acid 2-tert-butyl-6-(3-tert-butyl-2-hydroxy-5-methyl-benzyl)-4-methyl-phenyl ester to a medium which comprises (II). R31 : unsubstituted 1-7C alkyl; R32 : 1-7C alkyl or 1-6C alkoxy (both unsubstituted); m, n, o : 0 or 1; R51 : 1-7C alkyl or 2-7C alkenyl (both unsubstituted); and R52 : unsubstituted 2-7C alkenyl. [Image] [Image] [Image].

NITROXYL COMPOUND, AND POLYMERIZATION INHIBITOR AND POLYMERIZATION INHIBITOR COMPOSITION USING SAME

The following compound, inhibitor, and composition are provided: a compound having low volatility, high nitroxyl group concentration, and high polymerization inhibitory activity; a polymerization inhibitor using the compound; and a polymerization inhibitor composition using the compound. They are a nitroxyl compound represented by the following formula, a polymerization inhibitor using the nitroxyl compound, and a polymerization inhibitor composition using the nitroxyl compound:

Inhibition of polymerization of unsaturated monomers

Disclosed herein is a method for inhibiting the premature polymerization of ethylenically unsaturated monomers comprising adding to said monomers an effective amount of a mixture comprising: A) at least one stable hindered nitroxyl compound having the structural formula: wherein R1and R4are independently selected from the group consisting of hydrogen, alkyl, and heteroatom-substituted alkyl and R2and R3are independently selected from the group consisting of alkyl and heteroatom-substituted alkyl; and X1and X2(1) are independently selected from the group consisting of halogen, cyano, COOR7, —S—COR7, —OCOR7, (wherein R7is alkyl or aryl), amido, —S—C6H5, carbonyl, alkenyl, or alkyl of 1 to 15 carbon atoms, or (2) taken together, form a ring structure with the nitrogen; and B) at least one inhibitor selected from the group consisting of ortho-quinone, ortho-hydroquinone, para-quinone, para-hydroquinone, and derivatives of the foregoing.

Inhibiting polymerization of vinyl aromatic monomers

When a nitroxyl compound is heated in an oxygen-free atmosphere with a vinyl aromatic monomer at 50-140 DEG C. for up to 60 days, it forms an activated inhibitor mixture which is superior to the nitroxyl compound itself in preventing the premature polymerization of a vinyl aromatic monomer during its processing and purification.

Polymerization inhibition of acrylates using blends of nitroxides

Ethylenically unsaturated carboxyl monomers, such as acrylic or methacrylic acid or their esters, are protected from premature polymerization during manufacture and storage in the presence or absence of water by the incorporation therein of an effective stabilizing amount of a blend two or more nitroxides. Some of these blends provide synergistic stabilization efficacy much superior to the stabilization results obtained by use of either nitroxide alone.

Method for inhibiting premature polymerization of vinyl aromatic monomers

Nitroxyl inhibitors in combination with some oxygen reduce the premature polymerization of vinyl aromatic monomers during the manufacturing processes for such monomers. Even small quantities of air used in combination with the nitroxyl inhibitors result in vastly prolonged inhibition times for said monomers.

Process for the preparation of N-oxyl hindered amine esters

When a tetraalkyl orthotitanate transesterification catalyst is used in the preparation of N-oxyl hindered amine esters, the N-oxyl compound is obtained in excellent yield and purity when moderate temperatures (90°-130° C.) and an aliphatic hydrocarbon solvent are used. The N-oxyl compounds are light stabilizers and also inhibitors for preventing the premature polymerization of ethylenically unsaturated monomers.

An Electron Spin Polarization Study of the Interaction of Photoexcited Triplet Molecules with Mono- and Polynitroxyl Stable Free Radicals

Time-resolved electron spin resonance (TR ESR) has been used to investigate the chemically induced dynamic electron polarization (CIDEP) generated by the interaction of stable free radicals with the triplet states of benzophenone, benzil, and 2-acetylnaphthalene.The stable radicals were mono-, di-, tri-, and tetranitroxyl free radicals possessing the 2,2,6,6-tetramethylpiperidine-N-oxyl moiety.All of the stable radical systems investigated were found to be emissively polarized by interaction with the triplet states, and the phase of polarization was independent of the sign of zero-field splitting (D) of the interacting triplet molecule.Possible and likely mechanisms of polarization transfer (creation) resulting from the interaction of photoexcited triplet molecules with nitroxyls in the strong electron exchange are discussed.The emissive CIDEP of nitroxyls observed in the interactions with triplet benzil, which has D > 0, provides strong support for the operation of the radical-triplet pair mechanism.Within the time scale of TR ESR experiments (ca. 10-7 - 10-6 s) no significant variation in the shape of the CIDEP spectra of the nitroxyls was observed, either in viscous media or in micelles.It is concluded that intramolecular spin exchange (or conformational change) of polynitroxyls occurs much faster than the time resolution of the experiment.

Inhibiting polymerization of vinyl aromatic monomers

The polymerization of a vinyl aromatic compound, such as styrene, during distillation or purification is very effectively inhibited by the presence of at least one stable nitroxyl compound together with at least one aromatic nitro compound.