MXPA98000062A - Improved method to make 4,6-dibenzoilresorcinols copula - Google Patents

Abstract

An improved method is provided for making 4,6-dibenzoylresorcinol dimers with methylene bridge in a single step in high yield amounts, in the method 4,6-dienbozilresorcinol is heated with a paraldehyde or an aromatic aldehyde in a carboxylic acid solvent in the presence of a strong acid catalyst

Description

IMPROVED METHOD TO DO, 6-DIBENZOILRE5QRCINOLE5 COPULATED FIELD OF THE INVENTION r, fs + a inv ^ ru ion refers? I was prayed to do everything, 6-di benzol i r esorcí is not copul '; .. Very part i or 1 arrn-ent e, the invention refers to making a dimeio with bridge > I read a 4, b-di benzol 1 osoroi oL in one step.

U) BACKGROUND OF THE INVENTION Thermoplastic substrates i co < such as polycarbonates, it is generated by many favorable properties, including clarity, flexibility, temperature, and temperature. deflection of heat, as well as dimensional stability. Many of these materials are transpar- ent and are conventionally used as replacements for glass in commercial applications. However, with an outline < :? a are susceptible to degradation or ultol et a. Ready results 70 unfavorable characteristics (ie include 1 lamiente and wear of the substrate surface). Recently, it becomes more common to see the moplastist substi- tutes such as Licarhonatos are being read outdoors. , it is important to impart properties 2! 5 < the nnat.ologic capacity to the subst. This is often achieved by treating the surface of the substrate with a weather resistant coating material, so that the coating material typically contains light-absorbing agents. I nvestment systems resistant to climatic conditions can be prepared by incorporating light absorbers, such as benzot pazoles and benzoon, and light stabilizers of hindered amine. Also, ultolet light absorbers are sometimes incorporated into the substrate material more or for odd weathering properties. However, it is often discovered that ultolet light absorbing compounds (hereinafter referred to as UV absorbers), themselves decompose upon exposure to the light of the last air. Prolonged exposure to sunlight, moisture, and thermal cyclization conditions can cause love to 1 and at the same time and formation of my crayon in the reversing material, reducing the transparency. This leads to a degradation of the favorable properties of the thermoplastic substrate which is what the UV absorbers are originally used to protect. Therefore, there is a continuing need to search for new efficient UV absorbing compounds. Recently, novel derivatives with methylene bridge of 4, β-dibenzoiioresorei noles having a phenol group in the bridge methylene have been discovered and are the subject of the patent application of E.U.A. co-pending, commonly assigned, Series Mo. (case of attorney RD-24,624). The claimed compounds are useful as ultolet light absorbers djv). To make * the novel compounds, vain steps were taken. An important step was L < \ [U 'i? Iw L in a compound of methyl acetate or novel intermediate, This compound had to be washed and separated from the filtrate and then mixed with, b ~ d? benzol 1 additional resorcinol or phenol pair-to form the derivatives with methyl wood bridge, fi-dibenzole Lresor- cium 1 .. Therefore, there is a need for an improved, simpler method of making the absorber -It's novel UV.

BRIEF DESCRIPTION OF THE INVENTION This invention satisfies the need to provide an improved method for making 4-, 6-d-benzoyl binders. 1 resorcmol with rnet bridge i Leño en un so I pass it in quantities of high performance. The method involves heating 4,6-diI-enzoyl i-esorei not L (DER) with a paraldehyde or an aromatic aldehyde in an acid-carboxylic acid solvent in the presence of a strong acid catalyst. The reaction produces a 4,6-d? Benzo-lorsorc-nol dimer with a methylene bridge in one step. The formation of the intermediate rnetylene acetate is eliminated, as is the use of a secondary ami. A preferred para-aldehyde is formaldehyde and a preferred carboxylic acid is acetic acid. A high yield is greater than approximately 60% of the product, and preferably greater than approximately 71% of the product, and most preferably greater than or equal to approximately 9% of the product. In a first step, the present invention is directed to an improved method for making a dirner with rnet bridge and Leño of 4, 6 -dibenzoi Lresoroi nol comprising the step of: heating a rnezcLa of 4, (5 -dibon The solvent and about one-half olar- or greater equivalent of a 1-aryloxydehyde or aromatic aldehyde in a solvent at a temperature of about 80-100 ° C for a number of hours. of enough time to make a dirner with a rnet bridge filled with 4,6-d-benzole-liter-cnol, said 4,6-dibenzoi-1-resorcinol having the formula where p and Ar2 are independently substituted or unsubstituted polyloylionic or substituted groups, and said dirner with methylene bridge of 4,6-d? benzo-lorsorc? nol tenien o L f "o rrn u 1 a where fír'i and At "2 are intenent enternent subcryptic or unsubstituted monocyclic or poli cyclic aryl groups, and R (-? <-, M, an nplo group or an alkyl chain linear or rituximated less than about 10 carbon atoms Another aspect of this invention is a method for preparing light absorbers uL rav lol e < comprising the step of mixing a mixture of a substituted or unsubstituted aplo group on 6, di-benzole 1 resorcmol, an acid catalyst, an organic solvent and sufficient Ldeh or aromatic ehido at a temperature V sufficient time for foaming with a rnet bridge and a log of 4, 6-d The present invention will be better understood by those skilled in the art from the detailed description set forth below, considered together with the accompanying chemical examples and drawings, and which form part of the invention. you of the memory dosep pt i va ..

DESCRIPTION OF THE INVENTION Sr has discovered that the dimers with 4,6-diol-benzole-1-resorcinol inetone bridge, useful as UV absorbers, can be made in high performance in a single step. This invention demonstrates this by preparing bis (2, di- hi ro i- 3, b ~ dibenzoi 1 feni 1)? net anus in a single step in high performance heating 4, 6-d? benzoilresorcmol with forrnaLdehyde in acid acota co in the presence of a strong acid catalyst. Also, bis (2,6-dihydroxy-3,5-dibenz ilfeni 1) phenemethane can be prepared in a single step by heating 4, fi-dibenzoyl resounds nol in excoso of aromatic aldehyde and acid catalyst. The one-step procedure that produces a very high throughput of the product with a desired methylene bridge in a single step is shown in Scheme 1. A depot of, 6-d? The substituted or unsubstituted 1-resorcinol enzyme is heated to between about 50 ° C at reflux temperature, and preferably between about 80-150 ° C, with slightly more than one molar equivalent of one to one or more aldehydes. aromatic and an acid catalyst in a suitable solvent.

SCHEME 1 III Pri and H? -2 are independently substituted or unsubstituted noncyclic cos or poly groups and R is H, an aplo group or a straight or branched alkyl chain having less than about 10 carbon atoms. of the reaction includes all possible sub- stitutions on the phenyl rings of the starting dibenzoyl ester. In addition, the reaction can be carried out in a variety of carboxylic acid solvent and perhaps also other solvents, and with a variety of catalysts, is strong acid. Acetic acid is an attractive solvent for this application because the starting materials have solubility meaning iva in the same, especially at high temperatures, while the product is precipitated. A variety of earboxylic acid solvents such as, but not limited to, acetic acid, propionic acid, hexanoic acid and sirnilic acid can be used. lus to "mineral acids" -are used as catalysts. The sulfate acid also works as the catcher. Pumps of paral dehydro-IORI-IO) n ", on para-formaldehyde or pa -aceto Ldohido .. Also, it is found that it is possible to use aromatic aldehydes to give derivatives with substitutions in the methylene group in the genders. with rnet bridge and wood of 4, fi-d and benzol 1 resorcinol There should be no limitation on the structure of the aromatic aldehyde Examples of aromatic aldehydes (ArCHO) are benzaldohi or, the various tolualdehydes, anisal ehidos and the like If an aromatic aldehyde is used, the reaction is carried out on an excess of the aldehyde and additional sunlight may be necessary. In another aspect of the invention, a mixture of di-benzoyl-resorcinol derivatives may be used as the starting material to give a product containing a mixture of products containing derivative, with a non-symmetrically substituted bridge of wood as shown in IB Structure IV where end, Ar'2, Ai'3 r .4 are independently aroma rings »ico s Substituted or unsubstituted and R is H, C1 to 012 alkyl or an appropriate group.

IV I o'-, if examples also serve to demonstrate the invention u iitias n > < -e 1 J in i í < - > its reach.

EXAMPLE 1 b Preparation of compound III; R = phenyl 4,6 Di benzole] resorcinol (6.36 grams, D minol), and 5 drops of concentrated sulfuric acid were added to 20 milliliters of benzaldehyde.

Appropriately 1? The mixture was stirred for approximately 24 hours after which the excess of benzyl ether was distilled under reduced pressure.The resulting oil was taken up in ethanol and cooled to give a dark mass. in a Soxhlet extractor and extracted with hot ethanol during Ib approximately 2 days. Evaporation of the resulting otanol solution gave 4. 0 grams (yield of b (!%) Of a yellow-orange solid. The formula for the compound iri 'is Z > , where ri Ar-2 phenyl, EXAMPLE 2 Preparation of compound III "; R = H 4, b -Di benzole 1 resorcinol (159 (1 grams, S moles) and normal pair (00 grams, 2.6? Moles) were suspended in 2000 thousand pounds of acetic acid. Glacial ico in a 5 liter round bottom flask equipped with an overhead stirrer *, a reflux condenser, thermometer and heating mantle, concentrated ferric sulphuric acid (0.0 grams, 0.08 mole'-), and the tempera It was then brought to 115 ° 0 to make a homogenous solution, Subsequently, solids began to form, and 250 milliliters of glacial acetic acid were added to facilitate stirring, After 5 hours the solution was cooled, filtered and the The filter cake was washed with acetic acid and then with 2-propanol, the filter cake was then taken up again in hot acetic acid, cooled, filtered and washed as before. at 110 ° C in a vacuum oven to give 1449.9 grams (89.5%) of a light yellow solid. Nuclear magnetic resonance imaging (NMR) showed that it was identical to b? s (2, 6-d? h? rox? -3, 5-d? benzo? 1 em 1) ethane prepared by an independent route. The compound formula l 1 where Ari and Ai '2 phenyl, and R IL EXAMPLE 3 Preparation of dibenzoyl resorcinol derivatives coupled to methylene: III '"', R = H + compound V + compound VI , 6-D? Benzo? 1 resorcinol (3.10 grams, 10 moles), 4,6-di (- »er-bu» 11 benzol 1) resor-cmol (4.90 grams, 10 rnrnoLes) paraiorrnaidohi do (0.48 grams,) 6 minolos), and 3 drops of concentrated sulphuric acid were combined in 25 thousand illicit acetic acid glacial. The reaction mixture was heated to reflux and stirred for about 7 hours after which it was cooled, washed with 2-propanol and water, filtered and dried in air to give a product (6.33 grams, 83%). %) whose NMR and mass spectrum analysis revealed that it was a mixture of compound ITT '' ', RH compound V and compound VI.

Compound V Compound VI

Claims (6)

I 3 NOVELTY OF THE INVENTION CLAIMS

1. - An improved method for making a lime with a metal bridge of 1, 6-di benzo i 1 resorcinol comprising the step of: heating a mixture of 4, Pi-di benzole, 1 rororeine and approximately the? n? t_Hd of molar equivalent or greater of? n alq? i 1 paraldehyde or aldehyde aromatize with an acid in a solvent at a temperature between 00 ° O and reflux temperature for a sufficient amount of time to make a number with a metal bridge of 4,6-dibenzoi 1 resor-ci nol, said 4, 6-d? benzol 1 resorcí nol taking the i orrnuJ a wherein Ap and Ar are independently substituted or unsubstituted aryl oncyclic or substituted polycyclic groups, and said dimer with a rnet bridge of 4, b- di benzole 1 resorcinol having the for-mul. where p and r-2 are independently subcluded or unsubstituted monocyclic or polyclonal groups CL), and R is H, an amino group or a linear or branched alkyl chain less than about 10 atoms of carbon; bond. 2.- An improved method to make a dirner with a wooden bridge, 6-d? benzoylresorcinol in accordance 15 with claim 1, further characterized in that the alkylaldehyde is for forme. 3. An improved method for making a dirner with a rnet bridge and a 4, 6-d? Benzo lorsorcolol log according to claim 1, further characterized in that the 20 to aromatic dehydrated is benzaldehyde. 4. An improved method for making a dirner with a metal bridge of 4, 6, 6, 6, 6 or 6, according to claim 2, further characterized by the diameter with a nylon bridge of 4, 6. -d? benzo? lresorc? nol has the 25 formula I S wherein Ari and Ar 'are independently monocyclic and substituted or unsubstituted polyalkyl groups, and R is H, or a linear or branched alkyl chain that is less than approximately 10 carbon atoms. 5.- An improved method to make a dimer with a mechanical bridge, 4, 6-di benzo and 1resorcmol in accordance with the rei indication 3, also characterized by the fact that the bridge with a bridge is filled with, 6 ~ i benzol 1 esorcí nol has the fo mu a where i = Ar-2 = R ~ phenyl. 6.- An improved method to make a dirner with methylene bridge of 4, 6-d? Benzo? Iresorcmol according to the invention L, characterized in addition because the solvent is excess of aiomatic aldehyde. (A method for propagating ultraviolet light absorbers, comprising the step of mixing a mixture of a substi tuted or unsubstituted group into a 4,6-dibenzoi lrosorcide L, an acidic acid ester, a solvent organic and sufficient for Ldehyde or aromatic aldehyde at a temperature and for a sufficient time to form a dirner with a metal bridge of 6-dibenzo and Lrosorei nol "B., - An improved method for making a di-benzoyl derivative 1 resorcí nol coupled to the grid that involves the step of: heating a mixture of 4,6-di benzole 11-ester and nol and approximately half molar or greater equivalent of an alkyl paraldehyde or aldehyde aromat LCO with an acid in a solvent at a temperature between approximately 00 ° C and reflux temperature for a sufficient amount of time to make derivatives with non-symmetrical substituted methyl bridge that have the formula wherein ri, r-2, r-3, r * are independently substituted or unsubstituted aromatic rings and K is H, C1 to 012 alkyl or an aplo group. 9. An improved method for making a derivative of dibenzoi 1 esorcinol coupled to mixed wood in accordance with claim 7, further characterized in that the alkylalparal is for dehyde form. 10. An improved method for making a mixed dibenzoylresorcmol derivative to mixed wood in accordance with claim 7, further characterized by the fact that the a1 of h i do a roma 11 co e s be riza 1 de h i do "