- NOVEL PROCEDURE FOR THE FORMATION OF 2H-BENZOTRIAZOLE BODIES AND CONGENERS
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The present invention relates to a process for the preparation of 2H-benzotriazole compounds and congeners, novel 2H-benzotriazole compounds and congeners and their use as UV absorbers in coatings and bulk plastics.
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Page/Page column 26
(2020/07/05)
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- Body-care and household products and compositions comprising specific sulfur-containing compounds
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Disclosed are stabilized body care products, household products, textiles and fabrics which comprise specific sulfur containing compounds. Dyed products and articles are effectively stabilized against color degradation. The products are for example skin-care products, hair-care products, dentifrices, cosmetics, laundry detergents and fabric softeners, non-detergent based fabric care products, household cleaners and textile-care products.
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- Preparation of 2-aryl-2H-benzotriazoles by zinc-mediated reductive cyclization of o-nitrophenylazophenols in aqueous media without the use of organic solvents
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Zinc powder-mediated reductive cyclization of o-nitrophenylazophenols in alkaline solution affords the corresponding 2-aryl-2H-benzotriazoles in high yields under mild reaction conditions. No organic solvents are used in the reaction and only minimal amounts in the work-up.
- Liu, Guo-Bin,Zhao, Hong-Yun,Yang, Hong-Jie,Gao, Xiang,Li, Miao-Kui,Thiemann, Thies
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p. 1637 - 1640
(2008/02/11)
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- METHOD FOR PREPARING 2-(2-HYRDROXYPHENYL)-2H-BENZOTRIAZOLE
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This invention provides a method for preparing 2-(2-hydroxyphenyl)-2H-benzotriazole of formula (I) below, consisting of steps of a) performing a first reduction in which hydrazine hydrate is added to a compound of formula (II) below with or without a phase transition catalyst in the presence of solvents which include a nonpolar solvent, water, and an alkaline compound, thereby preparing a compound of formula (III) below, and b) performing a second reduction in which water is added to the compound of formula (III) prepared in step a), and then zinc powder and sulfuric acid are added thereto with or without the phase transition catalyst, wherein, X is halogen or hydrogen, R is hydrogen, C1-C12 alkyl, C5-C8 cycloalkyl, phenyl, or phenyl-C1-C4 alkyl; and R' is C1-C12 alkyl, C5-C8 cycloalkyl, phenyl, or phenyl-C1-C4 alkyl
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- 4-Formyl amino-n-methylpiperidine derivatives, the use thereof as stabilisers and organic material stabilised therewith
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The present invention relates to 4-formylamino-N-methylpiperidine derivatives of the formula (I) where the variables are as defined in the Description, to a process for preparing these piperidine derivatives, to the use of these piperidine derivatives of the invention, or prepared according to the invention, for stabilizing organic material, in particular for stabilizing plastics or coating materials, and also to the use of these piperidine derivatives of the invention, or prepared according to the invention, as light stabilizers or stabilizers for wood surfaces. The present invention further relates to stabilized organic material which comprises these piperidine derivatives of the invention or prepared according to the invention.
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- Processes for the preparation of benzotriazole UV absorbers
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Provided is a process for preparing 2H-benzotriazole UV absorbers containing a perfluoroalkyl moiety at the 5-position of the benzo ring, for example a trifluoromethyl group, which involves diazotizing the perfluoroalkyl substituted o-nitroaniline using concentrated sulfuric acid plus sodium nitrite or nitrosylsulfuric acid to form the corresponding monoazobenzene intermediate via the diazonium salt intermediate which is reduced to the corresponding 5-perfluoroalkyl substituted 2H-benzotriazole UV absorber compound by conventional reduction means. Also provided is a novel one-pot, multiphase reaction for the preparation of 2(2-nitrophenylazo) substituted phenols, which are precursors for 2H-benzotriazole UV absorbers.
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- 2-(2′-hydroxyphenyl)benzotriazoles used as U.V. stabilizers
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2-(2′-hydroxyphenyl)benzotriazoles having general formula (I). The above 2-(2′-hydroxyphenyl)benzotriazoles are useful as light stabilizers for organic polymers.
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- 2-(2′-hydroxyphenyl) benzotriazoles containing a 2,4-imidazolidinedione group and process for their preparation
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2-(2′-hydroxyphenyl)benzotriazoles having general formula (I). The above 2-(2′-hydroyzphenyl)benzotriazoles having general formula (I) are useful as heat, oxygen and light stabilizers for organic polymers. In particular they are useful as UV stabilizers for organic polymers.
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- Electrochemical synthesis of 2-aryl-2H-benzotriazoles and their N-oxides by controlled potential cathodic electrolysis
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Using a divided cell, reductive cyclizations of o-nitrophenylazo dyes (1) toward 2-aryl-2H-benzotriazole-1-oxides (2) or 2-aryl-2H-benzotriazoles (3) were successfully accomplished by the controlled potential cathodic electrolysis reactions. 1 was transformed to 2 under neutral conditions while 1 was transformed to 3 under basic conditions.
- Kim, Byeong Hyo,Lee, Doo Byung,Kim, Dae Ho,Han, Rongbi,Jun, Young Moo,Baik, Woonphil
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p. 841 - 850
(2007/10/03)
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- Liposomogenic UV absorbers
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PCT No. PCT/EP96/00959 Sec. 371 Date Sep. 15, 1997 Sec. 102(e) Date Sep. 15, 1997 PCT Filed Mar. 7, 1996 PCT Pub. No. WO96/29302 PCT Pub. Date Sep. 26, 1996There are described liposomogenic UV absorbers, comprising a hydrophilic head group (=Z), a spacer (=W), a UV chromophore (Q) having an absorption in the range from 285 to 400 nm and at least one hydrophobic tail group (=A) of the formula (1), in which A1 and A2, independently of one another, are a hydrophobic radical, Q is a UV chromophore, W is an organic radical, Z1 and Z2, independently of one another, are a hydrophilic radical, n1 and n2, independently of one another, are a number from 0 to 4, n1=n2=0 not being additionally included, p is 1 or 2, q is a number from 0 to 3, r1 is 1 or 2, r2 is 0 or 1, and s1 is a number from 1 to 3. The liposomogenic UV absorbers according to the invention are preferably used as sunscreen agents in cosmetic preparations. They are capable of self-organization into bimolecular layers, and can thereby penetrate into the stratum corneum to a high extent and behave there in an extremely wash-resistant manner.
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- Photostimulated reductive cyclization of o-nitrophenylazo dyes using sodium hydroxide in isopropyl alcohol. A new synthesis of 2-aryl-2H- benzotriazoles
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o-Nitrophenylazo dyes with NaOH were irradiated in isopropyl alcohol to give the corresponding benzotriazoles. The photostimulated reductive cyclization proceeds through the formation of N-oxides as an intermediate.
- Baik, Woonphil,Yoo, Chang Hyun,Koo, Sangho,Kim, Hern,Hwang, Yong Hyun,Kim, Byeong Hyo,Lee, Seok Woo
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p. 1779 - 1783
(2007/10/03)
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- Phosphites and their production and use
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Phosphites represented by the general formula (I): STR1 wherein R1, R2, R4 and R5 independently represent a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms or a phenyl group; R3 and R6 independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms; X1 is a dihydric alcohol residue, wherein HO--X1 --OH defines the corresponding dihydric alcohol from which residue X1, is obtained; and X2 is a direct bond or an alkylene group having 1 to 8 carbon atoms; and the phosphites are useful as stabilizers for organic materials.
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- 2-bromo-2-nitropropane/zn promoted reductive cyclizations of ortho-carbonyl, imino, or azo substituted nitrobenzenes
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Under the mild conditions, reductive cyclizations of 2-nitrobenzaldehydes, 2'-nitroacetophenone, and N-(2-nitrobenzylidene)anilines were accomplished in the presence of 2-bromo-2-nitropropane/Zn in methanolic solution. Under the similar conditions in MeOH/CH2Cl2, o-nitro-substituted phenylazobenzenes have been converted into 2-aryl-2H-benzotriazoles via reductive cyclizations that are widely used as UV absorbers. Synthesis and mechanistic details are discussed.
- Kim, Byeong Hyo,Lee, Yoon Seok,Kwon, Woong,Jin, Youngoo,Tak, Jung Ae,Jun, Young Moo,Baik, Woonphil,Lee, Byung Min
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p. 2581 - 2592
(2007/10/03)
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- Reductive cyclization of o-nitrophenylazobenzenes to 2-aryl-2H- benzotriazoles by SmI2
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In a mild reaction with SmI2, ortho-nitro substituted phenylazobenzenes have been converted into 2-aryl-2H-benzotriazoles.
- Kim, Byeong Hyo,Kim, Sun Kyong,Lee, Yoon Seok,Jun, Young Moo,Baik, Woonphil,Lee, Byung Min
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p. 8303 - 8306
(2007/10/03)
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- Microbial deoxygenation of N-oxides with Baker's yeast-NaOH
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The microbial deoxygenation of a series of aromatic and heteroaromatic N-oxide compounds, including quinoline N-oxides, isoquinoline N-oxides, 2-aryl-2H-benzotriazole 1-oxides, benzo[c]cinnoline N-oxide and azoxybenzenes, has been performed with bakers'yeast-NaOH.
- Baik, Woonphil,Kim, Dong Ik,Koo, Sangho,Rhee, Jong Uk,Shin, Sung Hee,Kim, Byeong Hyo
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p. 845 - 848
(2007/10/03)
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- Piperidine compound, a process for producing the same and a stabilizer using the same
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2-Methyl-3-(2,2,6,6-tetramethyl-4-piperidylamino)-N-(2,2,6,6-tetramethyl-4-piperidyl)-propionamide represented by the following formula, a process for producing the same and a stabilized organic material composition containing the same wherein the piperidine compound imparts excellent properties, such as light stability or thermal stability to the organic materials. STR1
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- Process for the preparation of benzotriazoles
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2-(2-Hydroxyphenyl)-2H-benzotriazoles of the formula STR1 in which R is hydrogen, C1 -C12 alkyl or C1 -C4 alkoxy, R1 is hydrogen, C1 -C12 alkyl, C5 -C6 cycloalkyl, phenyl or phenyl-C1 -C4 alkyl and R2 is C1 -C12 alkyl, C5 -C6 cycloalkyl, phenyl, phenyl-C1 -C4 alkyl or a group --Cn H2n --COOR3, in which n is 0 to 4 and R3 is hydrogen or C1 -C12 alkyl, can be prepared particularly advantageously by catalytic hydrogenation of a suitable o-nitroazo compound in the presence of a Pt, Pd, Pt/Pd or Rh hydrogenation catalyst and an alkylenediamine or an acyclic or cyclic polyalkylene polyamine in a halogenated or nonhalogenated aromatic hydrocarbon as solvent.
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- Method of preparing 2-phenyl benzotriazoles
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A method of preparing 2-phenylbenzotriazoles expressed by Formula I: STR1 (wherein R1 denotes a hydrogen or chlorine atom, a lower alkyl group having 1 to 4 carbon atoms, a lower alkoxyl group having 1 to 4 carbon atoms, a carboxyl group or a sulfonic acid group; R2 denotes a hydrogen or chlorine atom, a lower alkyl group having 1 to 4 carbon atoms or a lower alkoxyl group having 1 to 4 carbon atoms; R3 denotes a hydrogen or chlorine atom, an alkyl group having 1 to 12 carbon atoms, a lower alkoxyl group having 1 to 4 carbon atoms, a phenyl group, a phenyl group substituted by an alkyl group having 1 to 8 carbon atoms, a phenoxy group or a phenylalkyl group with an alkyl part having 1 to 4 carbon atoms; R4 denotes a hydrogen or chlorine atom, a hydroxyl group or an alkoxyl group having 1 to 4 carbon atoms; and R5 denotes a hydrogen atom, an alkyl group having 1 to 12 carbon atoms or a phenylalkyl group with an alkyl part having 1 to 4 carbon atoms) comprises reduction with hydrogen of o-nitroazobenzene derivatives expressed by Formula II: STR2 (wherein R1, R2, R3, R4 and R5 each denote the same as in Formula I), the reduction being effected in a solvent containing water.
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- Method of preparing 2-phenyl benezothriazoles
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A method of preparing 2-phenylbenzotriazoles expressed by Formula I: STR1 (wherein R1 denotes a hydrogen or chlorine atom, a lower alkyl group having 1 to 4 carbon atoms, a lower alkoxyl group having 1 to 4 carbon atoms, a carboxyl group or a sulfonic acid group; R2 denotes a hydrogen or chlorine atom, a lower alkyl group having 1 to 4 carbon atoms or a lower alkoxyl group having 1 to 4 carbon atoms; R3 denotes a hydrogen or chlorine atom, an alkyl group having 1 to 12 carbon atoms, a lower alkoxy group having 1 to 4 carbon atoms, a phenyl group, a phenyl group substituted by an alkyl group having 1 to 8 carbon atoms, a phenoxy group or a phenylalkyl group with an alkyl part having 1 to 4 carbon atoms; R4 denotes a hydrogen or chlorine atom, a hydroxyl group or an alkoxyl group having 1 to 4 carbon atoms; and R5 denotes a hydrogen atom, an alkyl group having 1 to 12 carbon atoms or a phenylalkyl group with an alkyl part having 1 to 4 carbon atoms) comprises reducing with hydrogen 2-phenylbenzotriazole-N-oxides expressed by Formula II: STR2 (wherein R1, R2, R3, R4 and R5 each denotes the same as in Formula I).
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- The Reaction of Some o-Nitroazobenzenes with Hydroxylamine
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The reaction of some representative o-nitroazobenzenes with hydroxylamine in ethanolic sodium hydroxide solution gave good to excellent yields of the corresponding 2-aryl-2H-benzotriazole 1-oxides.In some cases, the corresponding parent 2-aryl-2H-benzotriazoles were also obtained.Under the same reaction conditions, nitrobenzene was essentially unreactive.It Is suggested that the reactive species is diimide.
- Wilshire, John F.K.
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p. 617 - 622
(2007/10/02)
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- Method for preparing 2-phenylbenzotriazoles and 2-phenylbenzotriazole-N-oxides
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This invention relates to a method for preparing a 2-phenylbenzotriazole of formula I, STR1 (wherein R1 represents hydrogen or chlorine atom, a lower alkyl group having a carbon number of 1 to 4, a lower alkoxyl group having a carbon number of 1 to 4, carboxyl group, or sulfonic acid group; R2 represents hydrogen or chlorine atom, a lower alkyl group having a carbon number of 1 to 4, or a lower alkoxyl group having a carbon number of 1 to 4; R3 represents hydrogen or chlorine atom, an alkyl group having a carbon number of 1 to 12, a lower alkoxyl group having a carbon number of 1 to 4, phenyl group, a phenyl group substituted with an alkyl group having a carbon number of 1 to 8, phenoxy group, or a phenylalkyl group, the alkyl part of which has a carbon number of 1 to 4; R4 represents hydrogen or chlorine atom, hydroxyl group, or a lower alkoxyl group having a carbon number of 1 to 4; and R5 represents hydrogen atom, an alkyl group having a carbon number of 1 to 12, or a phenylalkyl group, the alkyl part of which has a carbon number of 1 to 4), which comprises reducing an o-nitroazobenzene of formula III, STR2 (wherein R1, R2, R3, R4 and R5 are as defined above) with an aldehyde reducing agent in the presence of an aromatic ketone catalyst and base. This invention further relates to a method for preparing a 2-phenylbenzotriazole of formula I as derfined above, which comprises reducing 1 mole 2-phenylbenzotriazole-N-oxide of formula II, STR3 (wherein R1, R2, R3, R4 and R5 are as defined above) with 1 to 4 mole aldehyde in the presence of an aromatic ketone catalyst and base. This invention still further relates to a method for preparing a 2-phenylbenzotriazole-N-oxide of formula II as defined above, which comprises reducing 1 mole o-nitroazobenzene of formula III as defined above with 1 to 2 mole aldehyde in the presence of an aromatic ketone catalyst and base.
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- Novel process for preparation of benzotriazoles using aryldiols and quinones
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Process for preparing 2-(2'-hydroxyphenyl)-benzotriazoles of the formula STR1 from 2-nitro-2'-hydroxyazobenzenes of the formula STR2 which comprises reducing a 2-nitro-2'-hydroxyazobenzene compound in a strongly basic medium in the presence of an aromatic dihydroxy or dioxo compound as catalyst and of an alcohol having more than one carbon atom. The 2-(2'-hydroxyphenyl)-benzotriazole compounds are known stabilizers for organic materials.
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- Preparation of 2-(2H-Benzotriazol-2-yl)phenols by the Reduction of 2-phenols with Thiourea S,S-Dioxide
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The reduction of 2-phenols 1 with thiourea S,S-dioxide and sodium hydroxide in a mixture of isopropyl alcohol and water at reflux provides 2-(2H-benzotriazol-2-yl)phenols 3 in excellent yields.
- Tanimoto, Shigeo,Kamano, Takayoshi
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p. 647 - 649
(2007/10/02)
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- The Reduction of Some o-Nitrophenylazo Dyes with Thiourea S,S-Dioxide (Formamidinesulfinic Acid): a General Synthesis of 2-Aryl-2H-benzotriazoles and Their 1-Oxides
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Thiourea S,S-dioxide (formamidinesulfinic acid) reacts with o-nitrophenylazo dyes in ethanolic alkali to give, depending on the reaction conditions, either the corresponding 2-aryl-2H-benzotriazoles or their 1-oxides.The reagent is particularly effective for preparing in high yield 2-(2'H-benzotriazol-2'-yl)phenols, which are important ultraviolet absorbers.The corresponding reductions involving ammonium sulfide and sodium dithionite were also examined.The former reagent was unsatisfactory; the latter reagent behaved erratically and was a less effective reducing reagent than thiourea dioxide.Nevertheless, conditions were established whereby sodium dithionite furnished the 2-(2'H-benzotriazol-2'-yl)phenols in high yield and purity.
- Rosevear, Judi,Wilshire, John F. K.
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p. 2489 - 2497
(2007/10/02)
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- The Reduction of Some o-Nitrophenylazo Dyes with Glucose: A General Synthesis of 2-Aryl-2H-benzotriazole 1-Oxides
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The reduction of some representative o-nitrophenylazo dyes in ethanolic alkali with glucose gives the corrsponding 2-aryl-2H-benzotriazole 1-oxides in excellent yield.These 1-oxides are rapidly reduced to the parent benzotriazoles at room temperature by means of zinc dust/ethanolic alkali.This method provides a convenient preparation for 5-chlorobenzotriazoles, which are otherwise readily dechlorinated by zinc dust under more vigorous conditions
- Rosevear, Judi,Wilshire, John F. K.
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p. 2089 - 2093
(2007/10/02)
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- Process for the production of 2-aryl-2H-benzotriazoles
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A process for the production of 2-aryl-2H-benzotriazoles comprises reducing and cyclizing the corresponding o-nitroazobenzenes with hydrogen at a temperature in the range of about 20° C. to about 100° C. and at a pressure in the range of about 15 psia (1 atmosphere) to about 1000 psia (66 atmospheres) in an alkaline medium at a pH over 10 in the presence of a nickel catalyst, preferably molybdenum-promoted Raney nickel. High yields of pure product are obtained directly with a concomitant reduction of undesired by-product and a reduction in effluent pollution problems.
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- Process for the production of 2-aryl-2H-benzotriazoles
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A process for the production of 2-aryl-2H-benzotriazoles comprises reducing and cyclizing the corresponding o-nitroazobenzenes with hydrogen at a temperature in the range of about 20° C. to about 100° C. and at a pressure in the range of about 15 psia (1 atmosphere) to about 1000 psia (66 atmospheres) in an organic solvent mixture containing an organic amine at a pH over 10 in the presence of noble metal hydrogenation catalyst, preferably palladium. High yields of pure product are obtained with a concomitant reduction of undesired by-products and a reduction in effluent pollution problems.
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- Process for the preparation of 2-aryl-2H-benzotriazoles
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A process for producing benzotriazoles of the formula I STR1 wherein R1 is hydrogen or chlorine, R2 is hydrogen, chlorine, C1 -C4 alkyl, C1 -C4 alkoxy, C2 -C9 alkoxycarbonyl, carboxyl or sulfo, R3 is C1 -C12 alkyl, C1 -C4 alkoxy, phenyl, (C1 -C8 alkyl)-phenyl, C5 -C6 cycloalkyl, C2 -C9 alkoxycarbonyl, chlorine, carboxyethyl or C7 -C9 phenylalkyl, R4 is hydrogen, C1 -C4 alkyl, C1 -C4 alkoxy, chlorine or hydroxyl, and R5 is hydrogen, C1 -C12 alkyl, chlorine, C5 -C6 cycloalkyl or C7 -C9 phenylalkyl, which process comprises treating a benzotriazole-N-oxide of the formula II STR2 wherein R1, R2, R3, R4 and R5 have the above meanings, at a temperature of 20°-150° C., with an amine; or treating an o-nitroazobenzene of the formula III STR3 wherein R1, R2, R3, R4 and R5 have the above meanings, at a temperature of 20°-150° C., with an amine.
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- 1-Aza-4-thiacyclohexane-4,4-dioxide derivatives
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New 1-aza-4-thiacyclohexane-4,4-dioxide derivatives are used alone or in combination with other stabilizers for stabilizing organic materials. The new compounds are prepared by reacting substituted diallylsulfides with ammonia, amines or hydrazines.
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