GB2179940A - Furan-3-carboxylic acid derivatives - Google Patents
Furan-3-carboxylic acid derivatives Download PDFInfo
- Publication number
- GB2179940A GB2179940A GB08621165A GB8621165A GB2179940A GB 2179940 A GB2179940 A GB 2179940A GB 08621165 A GB08621165 A GB 08621165A GB 8621165 A GB8621165 A GB 8621165A GB 2179940 A GB2179940 A GB 2179940A
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- alkyl
- acid derivative
- hydrogen
- furancarboxylic acid
- formula
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D405/00—Heterocyclic compounds containing both one or more hetero rings having oxygen atoms as the only ring hetero atoms, and one or more rings having nitrogen as the only ring hetero atom
- C07D405/02—Heterocyclic compounds containing both one or more hetero rings having oxygen atoms as the only ring hetero atoms, and one or more rings having nitrogen as the only ring hetero atom containing two hetero rings
- C07D405/12—Heterocyclic compounds containing both one or more hetero rings having oxygen atoms as the only ring hetero atoms, and one or more rings having nitrogen as the only ring hetero atom containing two hetero rings linked by a chain containing hetero atoms as chain links
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D405/00—Heterocyclic compounds containing both one or more hetero rings having oxygen atoms as the only ring hetero atoms, and one or more rings having nitrogen as the only ring hetero atom
- C07D405/14—Heterocyclic compounds containing both one or more hetero rings having oxygen atoms as the only ring hetero atoms, and one or more rings having nitrogen as the only ring hetero atom containing three or more hetero rings
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/16—Nitrogen-containing compounds
- C08K5/34—Heterocyclic compounds having nitrogen in the ring
- C08K5/3412—Heterocyclic compounds having nitrogen in the ring having one nitrogen atom in the ring
- C08K5/3432—Six-membered rings
- C08K5/3435—Piperidines
Abstract
Novel furancarboxylic acid derivatives of the general formula I <IMAGE> wherein R<1>, R<2> and R<3> independently of one another are each hydrogen, alkyl, cyclohexyl or phenyl, but are not all hydrogen, and R<4> is a radical of the formula <IMAGE> where A is a bridge member which contains a heterocyclic ring or a C1-C12-alkylene group which may be interrupted by up to 3 ether oxygen atoms or nitrogen atoms, R<5> is C7-C12-aralkyl or C4-C12-cycloalkylalkyl or C1-C12-alkyl containing a heterocyclic structure, and R<6> is a radical of the formula <IMAGE> in which R<7>, R<8>, R<9> and R<10> are each C1-C4-alkyl, or R<7>, and R<8> or R<9> and R<10> together may form a tetra- or pentamethylene bridge, and R<11> is hydrogen, C2-C16-acyl, C1-C8-alkyl, C3-C8-alkenyl, C2-C4-hydroxyalkyl or aralkyl, and their salts, are useful light stabilizers for organic polymers, in particular olefin polymers.
Description
SPECIFICATION
Furan-3-carboxylic acid derivatives
It is known that 2,2,6,6-tetraalkylpiperidine derivatives are excellent light stabilizers for organic polymers. Furancarboxylic acid derivatives have also been disclosed as such stabilizers.
German Laid-Open Application DOS 2,258,752 describes tetraalkylpiperidinyl esters of furan-2carboxylic acid and of furan-2,5-dicarboxylic acid. WO 81 02 021 mentions the tri-(2,2,6,6tetramethyl-4-piperidinyl) ester of a furantricarboxylic acid which is not defined exactly. Finally,
German Laid-Open Application DOS 2,623,422 describes tetraalkylpiperidinyl esters of furan-2carboxylic acid.
German Patent 2,040,975 claims tetraalkylpiperidinylamides of furan-2-carboxylic acid and of furan-2,3,4-tricarboxylic acid, while German Patent 2,349,962 describes pentaalkylpiperidinylamides of furan-2-carboxylic acid.
A common feature of the 2,2,6,6-tetraalkyl-4-piperidinyl furancarboxylates described to date is the fact that they contain one or more carboxyl groups in the 2-position of the heterocyclic ring.
Surprisingly, we have found that the novel 2,2,6,6-tetraalkyl-4-piperidinyl derivatives of alkylsubstituted furan-3-carboxylic acids have a stabilizing effect which is substantially superior to that of the corresponding furan-2-carboxylic acid derivatives.
The present invention relates to furancarboxylic acid derivatives of the general formula I
where R', R2 and R3 independently of one another are each hydrogen, alkyl, cyclohexyl or phenyl, but not more than two of these radicals are simultaneously hydrogen, and R4 is a radical of the formula
where A is a bridge member which contains a heterocyclic ring or contains C,-C,2-alkyl which may be interrupted by up to 3 ether oxygen atoms or nitrogen atoms, R5 is C7-C12-aralkyl or
C4-C12-cycloalkylalkyl or C,-C,2-alkyl containing a heterocyclic structure, and R6 is a radical of the formula
in which R7, R8, R9 and R'O are each C,-C4-alkyl, or R7 and R8 or R9 and R'O together form a tetra- or pentamethylene bridge and R" is hydrogen, C2-C16-acyl, C1-C8-alkyl, C3-C8-alkenyl,
C2-C4-hydroxyalkyl or C7- to C"-aralkyl, and their salts.
Within the scope of the general definitions, alkyl radicals R', R2, R3, R7, R8, R9, R10 and R11 are each a straight-chain or branched group CH2,+1 the straight-chain radicals being preferred.
Specific examples are:
and preferably CH3, C2H5, C3H7 or C4H9.
R5 is, for example, benzyl, phenylethyl, 2,4-dimethoxyphenylethyl, 2-(pyrrolidin-1-yl)-ethyl, 2 (morpholin-4-yl)-ethyl, 2-(piperazin- 1 -yl)-ethyl, cyclohexylmethyl or cyclohexylethyl.
Examples of other radicals R11 are acetyl, propionyl, butyryl, hexanoyi, ss-ethylhexanoyl, allyl;-P- hydroxyethyl, fi-hydroxypropyl, benzyl and phenylethyl.
Examples of bridge members A are radicals of the formulae
Preferred compounds of the formula I are those in which R1, R2 and R3 are each hydrogen or methyl and R7, R8, R9 and R10 are each methyl.
The derivatives obtained from 2,4- or 2,5-dimethylfuran-3-carboxylic acid or from 2,4,5-trimethylfuran-3-carboxylic acid are particularly preferred.
Other particularly preferred compounds are those in which Ra, R2, R7, R8, R9 and R10 are each
CH3 and R3 is H.
R5 is preferably benzyl, phenylethyl or 2,4-di-methoxyphenylethyl, and R11 is preferably hydrogen, methyl, allyl, benzyl or acetyl.
The compounds according to the invention can be prepared by well-known chemical methods.
The furancarboxylic acid piperidinylamides can be obtained, for example, either from the corresponding acyl halides and the substituted 4-amino-2,2,6,6-tetraalkylpiperidines in the presence of an acid acceptor, such as an organic amine, an alkali metal hydroxide or an alkali metal carbonate, or from the corresponding methyl or ethyl esters by reaction with 4-amino-2,2,6,6tetraalkylpiperidines in the presence of a catalytic compound such as titanium tetrabutylate. The amides are advantageously obtained via the acyl halides.
The preparation of the furan-3-carboxylic acid derivatives required as starting compounds is known from the literature. For example, methyl 2,5-dimethylfuran-3-carboxylate can be prepared by the processes described in German Laid-Open Applications DOS 2,207,098 and DOS 2,826,013.
Ethyl 2-methyl-5-ethylfuran-3-carboxylate and corresponding esters containing larger alkyl groups in the 5-position of the furan ring are described in J. Org. Chem. 43 (1978), 4596.
Ethyl 2-methyl-5-phenylfuran-3-carboxylate can be prepared by the method described in Bull.
Soc. Chim. France 6 (1970), 2272.
Methyl 2,4-dimethylfuran-3-carboxylate and methyl 2,4,5-trimethylfuran-3-carboxylate can be prepared, for example, by the method described in Anales real soc. espan. fis. y quim. (Madrid) 50 B (1954), 407-412 [C.A. 49 (1955), 13,207c].
Methyl 2-methyi-4-ethylfuran-3-carboxylate can be prepared similarly to methyl 2,4-dimethylfuran-3-carboxylate, using 1-hydroxybutan-2-one instead of hydroxyacetone.
The synthesis of methyl 2-methylfuran-3-carboxylate is described in, for example, German Laid
Open Application DOS 2,800,505 or J. Chem. Soc., Perkin Trans. 1, 1981, 1982-1989.
The preparation of other alkyl-substituted furan-3-carboxylic acid esters is described in the literature.
The acyl chlorides can be prepared by a conventional method, for example by hydrolyzing the methyl or ethyl ester of the appropriate acid to give the free acid and then reacting the latter with thionyl chloride or with another suitable compound to give the acyl chloride.
The novel compounds may be in the form of the free base or of a salt. Suitable anions are derived from, for example, inorganic acids and,. in particular, organic carboxylic acids.
Examples of inorganic anions are chloride, bromide, sulfate, methosulfate, phosphate and thiocyanate.
Examples of carboxylic acid anions are formate, acetate, propionate, hexanoate, cyclohexanoate, lactate, stearate, dodecylbenzoate, benzoate, acrylate, methacrylate, citrate, malonate and succinate, and anions of polycarboxylic acids containing up to 3000 C00H groups and of dialkylfurancarboxylic acids. Details of the preparation are given in the Examples.
The novel compounds are useful for stabilizing organic material, especially plastics, to degradation due to light and heat. They are added to the plastics to be stabilized, suitably in a concentration of from 0.01 to 5, preferably from 0.02 to 1, % by weight, before, during or after polymer formation.
Any known apparatus and method for mixing stabilizers or other additives into polymers can be used for mixing the novel compounds with the plastics to be stabilized.
The plastics stabilized with one of the novel compounds can, if required, contain further additives, for example antioxidants, light stabilizers, metal deactivators, antistatic agents, flameretardant agents, pigments and fillers.
Antioxidants and light stabilizers which can be added to the plastics in addition to the novel compounds are, for example, compounds based on sterically hindered phenols, or costabilizers containing sulfur or phosphorus.
Examples of phenolic antioxidants of this type are 2,6-di-tert-butyl-4-methylphenol, n-octadecyl fl-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionate, 1,1,3-tris-(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, 1 ,3,5-trimethyl-2,4,6-tris-(3 ,5-di-tert-butyl-4-hydrnxybenzyl)-benzene, 1 ,3,5-tris-(3,5-di- tert-butyl-4-hydroxybenzyl) isocyanurate, 1,3,5-tris-[ss-(3,5-di-tert-butyl-4-hydroxyphenyl)-propiony- loxyethyl] isocyanurate, 1 ,3,5-tris-(2,6-dimethyl-3-hydroxy-4-tert-butylbenzyl) isocyanurate, pentaerythritol tetrakis-[fl-(3, 5-di-tert-butyI4-hydrnxyphenyl)-prnpionateJ, etc.
Examples of phosphorus-containing antioxidants are tris-(nonylphenyl) phosphite, distearyl pentaerythritol diphosphite, tris-(2,4-di-tert-butylphenyl) phosphite, tris-(2-tert-butyl-4-methylphenyl) phosphite, bis-(2,4-di-tert-butylphenyl) pentaerythritol diphosphite, tetrakis-(2,4-di-tert-butylphenyl) 4,4'-biphenylene diphosphite, etc.
Examples of sulfur-containing antioxidants are dilauryl thiodipropionate, dimyristyl thiodipropionate, distearyl thiodipropionate, pentaerythritol tetrakis-(ss-laurylthiopropionate), pentaerythritol tet rakis-(ss-hexylthiopropionate), etc.
Examples of other antioxidants and light stabilizers which may be used together with the compounds according to the invention are 2-(2'-hydroxyphenyl)-benzotriazoles, 2-hydroxybenzophenones, aryl esters of hydroxybenzoic acids, a-cyanocinnamic acid derivatives, nickel compounds and oxalic acid dianilides.
Examples of organic polymers which can be stabilized by the novel compounds are polymers of mono- and diolefins, such as low density or high density polyethylene, linear low density polyethylene, polypropylene, polyisobutylene, polybut- 1 -ene, polymethylpent-1-ene, polyisoprene or polybutadiene, and copolymers of mono- or diolefins or blends of the stated polymers; copolymers of mono- or diolefins with other vinyl monomers, eg. ethylene/alkyl acrylate copolymers, ethylene/alkyl methacrylate copolymers, ethylene/vinyl acetate copolymers or ethylene/acrylic acid copolymers; polystyrene; copolymers of styrene or a-methylstyrene with dienes or acrylyl derivatives, eg. styrene/butadiene, styrene/acrylonitrile, styrene/ethyl methacrylate, styrene/butadiene/ethyl acrylate or styrene/acrylonitrile/methyl acrylate;ABS, MBS and similar polymers; halogen-containing polymers, eg. polyvinyl chloride, polyvinyl fluoride, polyvinylidene fluoride and their copolymers; polymers derived from a,fl-unsaturated acids and their derivatives, such as polyacrylates and polymethacrylates, polyacrylamides and polyacrylonitriles; polymers derived from unsaturated alcohols and amines or their acrylyl derivatives or acetals, such as polyvinyl alcohol or polyvinyl acetate; polyurethanes, nylons, polyureas, polyesters, polycarbonates, polysulfones and polyethersulfones.
Other organic polymers which can be stabilized with the novel compounds are industrial coatings. Particularly noteworthy among these are baking finishes, including automotive finishes, preferably two-coat finishes.
Here too, the stated antioxidants and light stabilizers may additionally be used.
Solid compounds according to the invention can be added to the coating in solid or dissolved form, and liquid compounds according to the invention can be added as such. Their good solubility in coating systems is particularly advantageous.
The novel compounds are preferably used in polyolefins, preferably ethylene and propylene polymers.
EXAMPLE 1 2,5-Dimethylfuran-3-carboxylic acid N-phenylethyl-N-(2,2,6,6-tetramethyl-4-piperidinyl) amide
28.6 g (0.18 mole) of 2,5-dimethylfuran-3-carbonyl chloride and 45.0 g (0.18 mole) of 4-N phenylethylamino-2,2,6,6-tetramethylpiperidine in 400 moles of toluene are refluxed together with 15.0 g of sodium carbonate for 24 hours. The mixture is left to cool, the precipitate is filtered off under suction and stirred in 1000 ml of 2 N sodium hydroxide solution for 0.5 hour, the mixture is extracted with ethyl acetate, the organic phase is evaporated down and the residue which remains is dried to give 46.2 g (72%) of a colorless compound of melting point 76-78"C.
Other compounds according to the invention are listed in Table 1; the symbols relate to formula I.
TABLE 1
Ex- Rs R2 R3 l R4 | Melting ample : point 2 CH3 CH3 H < H2C-H - H2C H 78 - ao OC SOCH3 CH3 CH3 H nco- H3COCH2CH2-H 130 - 132 OC OCH3 CH3 H CH3 H3cO#CH2cH2-\NH 96 - 98 OC S H3 H3 H C N-CH2CH2 CH CH H I H I 1680 Cl 0.1 mi Hg 6 CH3 CH3 H CH2-N(CH2)3 NH M.p.1Z-1270C CH2 tH2 v ( H H3C5WCHl EXAMPLE 7
10.0 g of the carboxamide from Example 1 are dissolved in 150 ml of methanol. 1.92 g of adipic acid are added, the mixture is heated until a clear solution is obtained, and the latter is evaporated down. 11.3 g (95%) of the adipic acid salt of melting poing 154-156"C are obtained.
Other compounds according to the invention are listed in Table 2; the symbols relate to formula I.
TABLE 2
Example R4 Melting point 8 As for Example 1, salt of 2,5 dimethylfuran-3-carboxylic acid 138 - 1400C 9 As for Example 1, salt of 2,4 dimethylf.uran-3-carboxylic acid 178 - 18doc 10 As for Example 2, salt of adipic acid 83 - 85 0c 11 As for Example 2, salt of 2,5 dimethylfuran-3-carboxylic acid 162 - 1630C 12 As for Example 1, salt of 2,4 dimethylfuran-3-carboxylic acid 148 - 1500C 13 As for Example 3, salt of adipic acid 80 - 830C
Claims (9)
1. A furancarboxylic acid derivative of the formula I
where R, R2 and R3 independently of one another are each hydrogen, alkyl, cyclohexyl or phenyl, but not more than two of these radicals are simultaneously hydrogen, and R4 is a radical of the formula
where A is a bridge member which contains a heterocyclic ring or contains CI-C,2-alkyl which may be interrupted by up to 3 ether oxygen atoms or nitrogen atoms, R5 is C7-C,2-aralkyl or
C4-C,2-cycloalkylalkyl or C1-C,2-alkyl containing a heterocyclic structure, and R6 is a radical of the formula
in which R7, R8, R9 and R10 are each C1-C4-alkyl, or R7 and R8 or R9 and R'O together may form a tetra- or pentamethylene bridge, and R" is hydrogen, C2-C,6-acyl, C,-C8-alkyl, C3-C8-alkenyl, C2-C4-hydroxyalkyl or aralkyl, and its salts.
2. A furancarboxylic acid derivative as claimed in claim 1, wherein R', R2 and R3 contain not more than 8 carbon atoms each.
3. A furancarboxylic acid derivative as claimed in claim 1, wherein R1, R2 and R3 are each independently hydrogen or methyl.
4. A furancarboxylic acid derivative as claimed in any of claims 1 to 3, wherein R', R8, R10 are each methyl and R11 is hydrogen, methyl, benzyl or acetyl.
5. A furancarboxylic acid derivative as claimed in any of claims 1 to 4, wherein R5 is benzyl, phenylethyl or 2,4-dimethoxyphenylethyl or A is -(CH2)3-N N-(CH2)3, -(CH2)3-O(CH2)-O-(CH2)3- or
6. A furancarboxylic acid derivative as claimed in any of claims 1 to 5 in the form of a salt of an organic carboxylic acid.
7. A furancarboxylic acid derivative as claimed in claim 1 and mentioned in any of the foregoing Examples
8. An organic polymer containing 0.01 to 5%, by meight of a furan carboxylic acid derivative as claimed in any of claims 1 to 7.
9. An olefin polymer containing 0.02 to 1%, by might, of a furancarboxylic acid derivative as claimed in any of claims 1 to 7.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE3531427 | 1985-09-03 |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB8621165D0 GB8621165D0 (en) | 1986-10-08 |
| GB2179940A true GB2179940A (en) | 1987-03-18 |
| GB2179940B GB2179940B (en) | 1989-08-31 |
Family
ID=6280029
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8621165A Expired GB2179940B (en) | 1985-09-03 | 1986-09-02 | Furan-3-carboxylic acid derivatives |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JPS6256482A (en) |
| CH (1) | CH669195A5 (en) |
| GB (1) | GB2179940B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0455588A1 (en) * | 1990-04-30 | 1991-11-06 | Ciba-Geigy Ag | Piperidine-triazine compounds for use as stabilizers for organic materials |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1318559A (en) * | 1970-01-08 | 1973-05-31 | Sankyo Co | Stabilisers for synthetic polymers |
| GB1492494A (en) * | 1975-05-28 | 1977-11-23 | Sankyo Co | Derivatives of 4-aminopiperidine |
| EP0149781A1 (en) * | 1983-12-15 | 1985-07-31 | BASF Aktiengesellschaft | Furane-3-carboxylic-acid derivatives |
-
1986
- 1986-08-13 CH CH324586A patent/CH669195A5/en not_active IP Right Cessation
- 1986-08-26 JP JP19827186A patent/JPS6256482A/en active Pending
- 1986-09-02 GB GB8621165A patent/GB2179940B/en not_active Expired
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1318559A (en) * | 1970-01-08 | 1973-05-31 | Sankyo Co | Stabilisers for synthetic polymers |
| GB1492494A (en) * | 1975-05-28 | 1977-11-23 | Sankyo Co | Derivatives of 4-aminopiperidine |
| EP0149781A1 (en) * | 1983-12-15 | 1985-07-31 | BASF Aktiengesellschaft | Furane-3-carboxylic-acid derivatives |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0455588A1 (en) * | 1990-04-30 | 1991-11-06 | Ciba-Geigy Ag | Piperidine-triazine compounds for use as stabilizers for organic materials |
| US5268401A (en) * | 1990-04-30 | 1993-12-07 | Ciba-Geigy Corporation | Piperidine-triazine compounds for use as stabilizers for organic materials |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6256482A (en) | 1987-03-12 |
| GB8621165D0 (en) | 1986-10-08 |
| CH669195A5 (en) | 1989-02-28 |
| GB2179940B (en) | 1989-08-31 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |