Patent Publication Number: US-3879420-A

Title: Method of producing mixed tricycloalkylidene peroxides

Description:
Story et al.  
 [ METHOD OF PRODUCING MIXED TRICYCLOALKYLIDENE PEROXIDES [75] Inventors: Paul Richard Story; Bunge Lee,  
 both of Athens, (3a.; Peter Busch, Willich, Germany [73] Assignee: Research Corporation, New York,  
 [22] Filed: May 15, 1972 [21] Appl. No.: 253,576  
  Related U.S. Application Data [63] Continuation-impart of Ser. No. 842,689, July 17.  
 1969. abandoned.  
 [52] U.S. Cl. 260/338 [51] Int. Cl C07d 19/00 [58] Field of Search 260/338 [56] References Cited UNITED STATES PATENTS 3.528.898 9/l970 Story 260/338 Apr. 22, 1975 OTHER PUBLICATIONS T. Ledaal, Acta Chem. Scand., 21 (1967), No. 6. pp.  
 Houben-Weyl, Methoden der Organischen Chemie, Vol. VIII (1952). p. 56.  
 Primary E.\&#39;aminerNorma S. Milestone Attorney, Agent, or Firm-Dennis P. Clarke; Harold L. Stowell [57] ABSTRACT Mixed cyclic trimeric peroxides are prepared by reacting 1,1 &#39;-dihydroperoxy dicyclic peroxides with cyclic ketones in liquid organic carboxylic acid solvents in the presence of strong acid catalysts at low temperatures.  
 The mixed trimeric peroxides are converted to mixed dimeric peroxides by allowing an organic carboxylic acid solution thereof containing a strong acid catalyst to stand at about room temperature for a short period of time.  
 7 Claims, No Drawings METHOD OF PRODUCING MIXED TRICYCLOALKYLIDENE PEROXIDES The work on which this application was based was financed in whole or in part by the Department of Health, Education and Welfare.  
 RELATED APPLICATIONS This application is a continuation-in-part of Application Ser. No. 842,689, filed July 17, 1969 and now abandoned.  
 BACKGROUND OF THE INVENTION Macrocyclic hydrocarbons and lactones are valuable compounds useful as odorants or intermediates for the preparation of odorants in the perfume industry. They may be prepared by decomposing the corresponding cyclic diand trimeric peroxides as described in US. Pat. No. 3,528,898. Obviously, the odorant characteristic of the macrocyclic compound will depend in each instance upon the ring size and the nature and location of the substituents thereon.  
  Diand trimeric peroxides decompose to form macrocyclic compounds according to the following reaction schemes:  
  Obviously, the ring size of the macrocyclic compounds will depend upon the ring sizes of the starting peroxides. It will be readily apparent that where the diand trimeric peroxides are symmetrical, i.e., x=y=z, their decomposition will yield macrocyclic compounds containing only 2x or 3x methylene (CH groups, respectively. Thus, the decomposition of tricyclopentylidene peroxide will yield cyclododecane and cyclotridecanolide; the decomposition of tricyclohexylidene peroxide will yield cyclopentadecane and cyclohexadecanolide, etc. Likewise, the decomposition of diheptylidene peroxide will yield cyclododecane and cyclotridecanolide, etc.  
  It will also be apparent that it would be impossible to produce macrocyclic compounds having 2x 2*: l or 3x i l methylene groups from symmetrical (xa =z) diand trimeric peroxides, respectively, since the decomposition of each succeeding member of the symmetrical diand trimeric peroxide families will yield macrocyclic hydrocarbons and lactones differing from the preceding group of products by the addition to the ring of 2 or 3 carbon atoms, respectively.  
  For example, it would be impossible to produce cyclotridecane from a symmetrical trimeric peroxide since tricyclopentylidene peroxide yields cyclododecane and the next highest member of the series, tricyclohexylidene peroxide yields cyclopentadecane. Similarly, it would be impossible to produce cyclotridecane from a symmetrical dimeric peroxide since diheptylidene peroxide yields cyclododecane and the next highest member of the series, dioctylidene peroxide, yields cyclotetradecane.  
  It will also be apparent that it would be impossible to produce macrocyclic hydrocarbons and lactones containing a single substituent or plural different substituents from symmetrical diand trimeric peroxides. Since in symmetrical peroxides each of the rings would contain the same substituent their decomposition would yield products containing 2 or 3 identical substituents, depending upon whether the starting material is a dior trimeric peroxide.  
  The provision of non-symmetrical diand trimeric peroxides, i.e., those of the above structure wherein one or more of x, y and z are different from each other, would enable the production of a wider variety of macrocyclic hydrocarbons and lactones having differing ring sizes and structures. Moreover, the provision of non-symmetrical peroxides containing only a single substituent or a wide variety of substituents would enable the production of substituted macrocyclic compounds heretofore unavailable in an efficient and economical manner.  
  Thus, a cyclotridecane could be produced by decomposing dipentylidene cyclohexylidene peroxide, a mixed trimeric peroxide. Similarly, cyclotridecane could be produced from heptylideneoctylidene peroxide. In addition, methoxycyclotridecane and methoxycyclotetradecanolide could be produced from dicyclopentylidene-4-methoxycyclohexylidene peroxide.  
  It should be readily apparent, therefore, that the provision of mixed trimeric and dimeric peroxides affords the perfume industry a less expensive and wider selection of macrocyclic hydrocarbons and lactones than heretofore available.  
  It is known that mixed organic trimeric peroxides may be prepared by reacting dihydroperoxy dicycloalkyl peroxides with liquid ketones. At pp. 5456 of Vol. 8 of Houben-Weyl, Methoden der Organischen Chemie (1952) there is disclosed a method for preparing isopropylidene dicyclohexylidene peroxide by treating l,- 1 -dihydroperoxydicyclohexyl peroxide with an excess of acetone in the presence of anhydrous cupric sulfate for 14 days. The use of hydrochloric acid as a catalyst is also disclosed. This method is limited to the employment of liquid ketones, however. Heretofore, no method has been suggested which permits the use of solid ketones.  
  Additional prior art relating to the production of organic peroxides includes an article by T. Ledaal in Acta. Chem. Scand., Vol. 21, (1967) pp. 165657 wherein it is disclosed that symmetrical or non-mixed dimeric peroxides may be prepared by treating a carboxylic acid solvent solution of a ketone&#39;hydroperoxide with a strong acid. When employing cyclopentanone hydroperoxide a non-mixed trimeric peroxide was produced.  
  Dilthey et al., in Vol. 154 of Jour. Prakt. Chem. (1939-40) at pp. 2l9237 disclose the oxidation of various ketones to produce non-mixed or symmetrical trimeric peroxides.  
  I-Ieretofore, however, there has existed no efficient method for the production of relatively high yields of mixed or non-symmetrical dior trimeric cyclic peroxides. a  
  It is an object, therefore, of the present invention to provide an efficient method for the production of mixed or non-symmetrical tricyelic peroxides.  
  It is a further object of the present invention to provide a method for the preparation of mixed or nonsymmetrical dicyclic peroxides by decomposition of the mixed trimeric peroxides.  
  It is a further object of the present invention to provide novel mixed or non-symmetrical diand tricyclic peroxides.  
 SUMMARY OF THE INVENTION It has been found that mixed cyclic trimeric peroxides may be prepared in short reaction times in high yields by reacting a 1,1-dihydroperoxy dicyclic peroxide with a cyclic ketone in a liquid organic carboxylic acid solvent in the presence of a catalytic amount of a strong acid catalyst at low temperatures.  
  The resulting mixed trimeric peroxide may be converted to a mixed dimeric peroxide by allowing an organic carboxylic acid solution thereof containing a catalytic amount of a strong acid catalyst to stand at about room temperature for a short period of time.  
 DETAILED DESCRIPTION OF THE INVENTION More specifically, it has been discovered that mixed tricyeloalkylidene peroxides in which at least one of the three of the cyclic ketone precursor molecules are not of the same structure, of the following general formula:  
 in which x, y and z are positive integers of from 4 to 17 may be prepared in high yields by treating a 1,1 dihydroperoxydicyclicperoxide of the following general formula:  
 OOH  
 in which x and y are positive integers of from 4 to 17 with a cyclic ketone of the following general formula:  
 in which 1 is a positive interger of from 4 to 17 in a liquid organic carboxylic acid wherein the ratio of peroxl ide to acid solvent is from 50 mmoles of peroxide in ml of acid solvent to 50 mmoles of peroxide in 3,000 ml of acid solvent, with the preferred ratio being 50 mmoles of peroxide to 100 ml of acid solvent, in the presence of a strong mineral or organic acid catalyst; the ratio of peroxide to acid catalyst being from 200 mmoles of peroxide to about 1 ml of concentrated acid to 200 mmoles of peroxide in 100 ml of concentrated acid with the preferred ratio being 200 mmoles of peroxide to ml of catalyst, at temperatures ranging from C to C with the preferred temperature being approximately 20C. The thus produced mixed trimeric peroxide is obtained as a solid simply by adding water or methanol to the above organic acid reaction solution after a sufficient reaction time of from a few minutes to several hours with the preferred time being 5 hours. The pure trimer is then obtained by washing the solid with water.  
  It is a further feature of the present invention that the mixed tricyclic peroxides of the present invention may be converted into mixed dicyclic peroxides which are new compositions of matter. The tricyclic peroxides are converted into excellent yields of the corresponding dicyclic peroxides by allowing a solution of the tricyclic peroxide in acetic acid or in propionic acid or a mixture of the two acids, and a mineral acid such as perchloric acid to stand at a temperature of from about 0C to about 50C, preferably about room temperature for short periods of time of from a few minutes to 24 hours. Alternatively, the trimeric peroxides may be converted into the dimeric peroxide by heating the reaction mixture in which they are produced to the above temperature. Generally, the same reactant, carboxylic acid solvent and catalyst proportions set forth above for production of the mixed trimeric peroxides may also be employed in preparing the dimeric peroxides. These mixed dicycloalkylidene peroxides decompose to give mixtures of macrocyclic compounds which are most useful in the perfume industry as odorants, for example, cyclononones and cycloundecanes. Substituted dicyclic peroxides containing the above-mentioned substituents may also be prepared according to the method of the invention.  
  The preparation of these mixed dicycloalkylidene peroxides is illustrated as follows:  
  C (I) 0 (K m m m/0 O\C/\ C (en (ca 2 a A X 2 y o o V (x.z)  
  Suitable liquid organic carboxylic acid solvents include the liquid, lower aliphatic, preferably lower alkanoic acids such as acetic, formic, propionic and butyric acids.  
  A wide variety of strong acid catalysts may be employed, such as perchloric, para toluene sulfonic, hydrochloric sulfuric and nitric acids.  
  While the above structural formulae do not include substituted peroxides, the method of the invention is also applicable to the preparation of various substituted mixed tricycloalkylidene peroxides. They may be substituted with the following groups: lower alkyl, hydroxy, lower alkoxy, carboxy, hydroxyloweralkyl, carboxyaryl, carboxyloweralkyl, etc. These peroxides produced by the method of the present invention are useful for the synthesis of macrocyclic compounds as described in US. Pat. No. 3,528,898. Obviously, the production of these types of macrocyclic compounds would be impossible utilizing symmetrically substituted peroxides.  
 in which x is a positive integer of from 4 to 17 and y is a positive integer of from 4 to 17. Not only does this process yield mixed dicycloalkylidene peroxides but also non-mixed dicycloalkylidene peroxides.  
 EXAMPLE I A solution of 5 mmoles of cyclopentanone in 10 ml of propionic acid was placed in a 50 ml Erlenmeyer flask containing a spinbar for magnetic stirring and cooled to just below 20C by adding dry ice to the solution. To this cooled solution was added with stirring 0.5 ml ofa perchloric acid solution, 10% in acetic acid, and 5 mmoles of 1,1 dihydroperoxydicyclopentyl peroxide. The temperature was maintained at about 20C for 1 hour after addition was completed. The temperature was then raised to 0C and kept there for 4 hours. At this time about 35 ml of water was added, resulting in separation of crystals. The separated product was washed with water and dried giving 1.09 grams of&#39;tricyclopentylidene peroxide, a 73% yield. The peroxide product was identified by infrared comparison, elemental analysis and by the nature of the products obtained on thermal decomposition of the peroxide, producing a macrocyclic compound.  
 EXAMPLE 11 A solution of 5 mmoles cyclohexanone and 10 ml of propionic acid was placed in a 50 ml Erlenmeyer flask containing a spinbar for magnetic stirring and cooled to just below 20C by adding dry ice to the solution. To the cooled solution was added with stirring 0.5 ml of a perchloric acid solution, 10% in acetic acid, and 5 mmoles of 1,1 dihydroperoxydicyclopentyl peroxide. The temperature was maintained at about 20C for 1 hour after addition was complete. The temperature was then raised to C and kept there for 4 hours. After this time, 35 ml of water was added, resulting in a separation of crystals. The crystals were washed and dried, giving a yield of 0.99 grams of dicyclopentylidene cyclohexylidene peroxide, a yield of 63%.  
 EXAMPLE Ill A solution of 5 mmoles of cycloheptanone in ml of propionic acid was placed in a 50 ml Erlenmeyer flask containing a spinbar for magnetic stirring and cooled to just below C by adding dry ice to the solution. To the cooled solution was added with stirring 0.5 ml ofa perchloric acid solution, 10% in acetic acid, and 5 mmoles of 1,1 dihydroperoxydicyclopentyl peroxide. The temperature was maintained at 20C for one hour after addition was complete. The temperature was then raised to 0 C and kept there for 4 hours. After this time, about 35 ml of water was added which resulted in separation of crystals. The crystals were washed with water and dried. The resulting product was dicyclopentylidenecycloheptylidene peroxide in the amount of 0.61 grams, a yield of 37%. The product was identified as in Example I.  
 EXAMPLE IV A solution of 5 mmoles of cyclopentanone in 10 ml of propionic acid was placed in a 50 ml Erlenmeyer flask containing a spinbar for magnetic stirring and cooled tojust below 20 C by adding dry ice to the solution. To the cooled solution was added with stirring 0.5 ml of a perchloric acid solution, 10% in acetic acid, and 5 mmoles of 1,1 dihydroperoxydicyclohexyl peroxide. The temperature was maintained at about 20 C for one hour after addition was complete. The temperature was then raised to 0 C and kept there for 4 hours. After this time, 35 ml of water was added resulting in a separation of crystals. The crystals were washed and dried. The produce was dicyclohexylidenecyclopentylidene peroxide in the amount of 1.02 grams, a yield of 62%. The product was identified as in Example 1.  
 EXAMPLE V A solution of 5 mmoles of cyclohexanone and 10 ml of propionic acid was placed in a 50 ml Erlenmeyer and 5 mmoles of 1,1 dihydroperoxydicyelohexyl per- I oxide. The temperature was maintained at about 20 C for 1 hour after addition was complete. The temperature was then raised to 0 C and kept there for 4 hours.  
 After this time, 35 ml of water was added resulting in crystal separation. The crystals were washed and dried. The product thus produced was tricyclohexylidene peroxide in the amount of 1.30 grams, a yield of 76%. The product was identified as in Example 1.  
 EXAMPLE VI A solution of 5 mmoles of cyclopentanone in 10 ml of propionic acid was placed in a 50 ml Erlenmeyer flask containing a spinbar for magnetic stirring and cooled to just below 20 C by adding dry ice to the solution. To the cooled solution was added with stirring 0.5 ml of a perchloric acid solution, 10% in acetic acid, and 5 mmoles of l,l-d1hydroperoxydicycloheptyl peroxide. The temperature was maintained at about 20 C for one hour after addition was complete. The temperature was then raised to 0 C and kept there for 4 hours. After this time, 35 ml of water was added resulting in crystal separation. The crystals were washed with water and dried. The product was dicycloheptylidenecyclopentylidene peroxide, 1.17 grams, a yield of 66%. The product was identified as in Example 1.  
 EXAMPLE V11 A solution of 50 mmoles of 4-methoxycyclohexanone and 20 ml of propionic was cooled down to 20 C by adding powdered dry ice. The solution was stirred and to it was added 02ml of 10% perchloric acid in acetic acid and 5 mmoles of l,1dihydroperoxydicyclododecyl peroxide. The temperature of the solution was maintained at 20 C for 1 V2 hours and then raised to 0 C and maintained at this temperature for 2 /2 hours. Water was added to the reaction mixture which yielded 2 grams of a colorless mass. After filtering, the mass turned pasty and it was stirred in methanol for 4 hours at 0 C which yielded a colorless crystalline product, dicyclododecyclidene-4-methoxycyclohexylidene peroxide, identified by infrared analysis.  
 EXAMPLE V111 A solution of 5 mmoles of 4-methoxycyclohexanone in 20 ml of propionic acid was placed in a ml Erlenmeyer flask containing .a spinbar for magnetic stirring and cooled to just below 20 C by adding powdered dry ice to the solution. To this solution was added 0.5 ml of 10% perchloric acid in acetic acid and 10 mmoles of 1,1 dihydroperoxydicyclopentyl peroxide. The temperature was maintained at about 20C for 2 hours after addition was completed. The temperature was then raised to about 0C and after 2 more hours, 100 ml of water was added to the reaction mixture, resulting in a heavy oil. This oil became a pasty mass by stirring with a large amount of water for several hours at 0C. The water was decanted and the reaction product dried. This product was dicyclopentylidene-4-methoxycyclohexylidene peroxide as identified by infrared analysis.  
  A 500 mg sample of the dicyclopentylidene-4- methoxycyclohexylidene peroxide was thermolyzed by refluxing in 10 ml decane for 2 hours. Gas chromatographical analysis of the reaction mixture which was identified by infrared analysis disclosed the decomposition products to be methoxycyclotridecane; 20% yield; methoxycyclotetradecanolide, approximately 20% yield; and the methoxy derivative of a cyclic dilactone containing 15 C. atoms.  
  The following examples are directed to the synthesis of mixed dicycloalkylidene peroxides from mixed tricycloalkylidcne peroxides.  
 EXAMPLE IX A solution 5 mmoles of cyclohexanone in 10 ml of propionic acid was placed in a 50 ml Erlenmeyer flask containing a spinbar for magnetic stirring and cooled to just below 20C by adding dry ice to the solution. To the cooled solution was added with stirring 0.5 ml of a perchloric acid solution, 10% in acetic acid, and 5 mmoles of 1,1 dihydroperoxydicyclopentyl peroxide. The temperature was maintained at about 20 C for 1 hour after addition was complete. At this point, the trimeric mixed peroxide, dicyclopentylidenecyclohexylidene peroxide was produced.  
  After maintaining the solution for one hour at -20 C, the temperature was raised to C and kept there for 4 hours. Thereupon, 25 ml of acetic acid and 1 ml of the perchloric acid solution, all at room temperature, were added to the reaction mixture with stirring. After 1 hour at room temperature, the mixture was diluted with about 100 ml of water. The crystalline solid which separated was filtered and washed with water and then recrystalized with acetone-water. A mixed dicycloperoxide was produced, cyclopentylidenecyclohexylidene peroxide and a non-mixed peroxide, dicyclohexylidene. The melting point of the mixed dicycloalkylidene peroxide was 78 105 and weighed 0.29 grams which gave a yield of 27%. These products were established by their photolysis in methylene chloride solvent which gave the corresponding macrocyclic hydrocarbon whose structures were determined by infrared analysis and mass spectral analysis.  
 EXAMPLE X A solution of 5 mmoles of cycloheptanone in ml of propionic acid was placed in a 50 ml Erlenmeyer flask containing a spinbar for magnetic stirring and cooled to just below C by adding dry ice to the solution. To the cooled solution was added with stirring 0.5 ml of a perchloric acid solution, 10% in acetic acid, and 5 mmoles of 1,1 dihydroperoxydicyclopentyl peroxide. The temperature was maintained at about 20 C for 1 hour after the addition was completed. At this point, a mixed peroxide was present, dicyclopentylidenecycloheptylidene.  
  Thereupon, ml of acetic acid and 1 ml of the perchloric acid solution, all at room temperature, was added to the reaction mixture with stirring. After 1 hour at room temperature, the mixture was diluted with about 100 ml of water. The crystalline solid which separated was filtered and washed with water and then recrystalized with acetone-water. The products thus produced were cyclopentylidenecycloheptylidene peroxide, a mixed dicycloalkylidene peroxide, melting point 49 55 C. in the amount of 0.29 grams representing a yield of 27%, and dicycloheptylidene peroxide. These compounds were identified as in Example IX.  
 EXAMPLE XI A solution of 5 mmoles of cyclopentanone in 10 ml of propionic acid was placed in a 50 ml Erlenmeyer flask containing a spinbar for magnetic stirring and cooled to just below -20 C by adding dry ice to the solution. To the cooled solution was added by stirring 0.5 ml ofa perchloric acid solution, 10% in acetic acid, and  
 5 mmoles of 1,1 dihydroperoxydicyclohexyl peroxide. The temperature was maintained at about -20 C for 1 hour after addition was complete.  
  A mixed tricycloalkylidene peroxide was produced, dicyclohexylidenecyclopentylidene. Thereupon, 25 ml of acetic acid and 1 ml of the perchloric acid solution, all at room temperature, was added to the reaction mixture with stirring. After 1 hour at room temperature, the mixture was diluted with about 100 ml of water. The crystalline solid which separated, was filtered and washed with water and recrystalized with acetonewater. The products produced are cyclopentylidenecyclohexylidene peroxide, a mixed dicycloalkylidene peroxide with a melting point of between 120 C, 0.66 grams representing a yield of 62%, and dicyclohexylidene. The products were identified as in Example 1X.  
 EXAMPLE XII A solution of 5 mmoles of cycloheptanone in 10 of propionic acid was placed in a 50 ml Erlenmeyer flask containing a spinbar for magnetic stirring and cooled to just below 20 C by adding dry ice to the solution. To the cooled solution was added with stirring 0.5 ml of a perchloric acid solution, 10% in acetic acid, and 5 mmoles of 1,1dihydroperoxydicyclohexyl peroxide. The temperature was maintained at about -20 C for 1 hour after addition was complete.  
  After this time, the temperature was raised to 0 C and kept there for 4 hours. Thereupon 5 ml of acetic acid and 1 ml of the perchloric acid solution, all at room temperature was added to the reaction mixture with stirring. After l hour at room temperature the mixture was diluted with about ml of water. The crystalline solid which separated was filtered and washed with water and then recrystalized with acetonewater. The products produced in this reaction were cyclohexylidenecycloheptylidene peroxide, a mixed dicycloalkylidcne peroxide with a melting point of between 90 C, 0.90 grams, a yield of 84%, dicyclohexylidene peroxide and dicycloheptylidene peroxide. These products were identified as in Example IX.  
 EXAMPLE XIII The exact procedure of Example IX was followed except cyclopentanone was used and the peroxide 1,1dihydropcroxydicycloheptyl was used. This gave reaction products of cyclopentylidenecycloheptylidene peroxide, a mixed dicycloalkylidene peroxide with a melting point of between 60 90 C, 0.53 grams representing a yield of 50%, and dicycloheptylidene peroxide.  
 EXAMPLE XIV The exact procedure of Example IX was used except 1,1&#39;dihydroperoxydicycloheptyl peroxide was used. The reaction products were cyclohexylidenecycloheptylidene peroxide, a mixed dicycloalkylidene peroxide with a melting point of between 82 84 C, 0.79 grams, a yield of 74%, dicyclohexylidene peroxide and dicycloheptylidene peroxide.  
 EXAMPLE XV The exact procedure of Example IX was followed except cyclooctanone ketone was used, and 1,1dihydroperoxydicycloheptyl peroxide was used. The reaction products were cycloheptylidenecyclooctylidene peroxide, a mixed dicycloalkylidene peroxide with a melting point of between 82 91 C, 0.53 grams representing a yield of 50%, and dicycloheptylidene peroxide.  
 EXAMPLE XVI The exact prodedure of Example IX was used except 1,1dihydroperoxydicyclohexyl peroxide was used. The reaction products were dicyclohexylidene peroxide which had a melting point of between 125 129 C, 1.03 grams representing a 97% yield.  
  The exact procedure of Example [X was used except cyclopentanone ketone was used. The reaction products were dicyclopentylidene peroxide with a melting point of between 94l04 C, 0.055 grams representing a yield of 5%.  
 EXAMPLE XVlll A solution of 5 mmoles of cyclododecanone in 10 ml of propionic acid was placed in a 50 ml Erlenmeyer flask containing a spinbar for magnetic stirring and cooled to approximately 20 C by adding dry ice to the solution. To the cooled solution was added with stirring 0.5 ml of 10% perchloric acid in acetic acid and 5 mmoles of l,ldihydroperoxydicyeloheptyl peroxide. The temperature was raised to C and kept there for 4 hours. Thereupon 35 ml of water was added resulting EXAMPLE XlX A solution of 30.4 mmoles, 3.78 grams, of freshly distilled cyclooctanone and 30 ml of acetonitrile was prepared. To this solution 2 ml of 98% hydrogen peroxide was added and the mixture was stirred for minutes at 0C, and then 5 drops of 70% perchloric acid were added. After 24 hours stirring at 0C, there was obtained a very viscous liquid which was treated with 30 ml of methanol. The reaction solution was allowed to stand for 24 hours at 0C, yielding 870 mg of tricyclooctylidene peroxide, 20% yield of colorless crystals, m.p. 72C75C.  
  A solution of 400 mg of tricyclooctylidene peroxide was refluxed in ml of decane for 3 hours. A gas chromatograph analysis showed three peaks whose retention times matched with the expected thermal decomposition products of the above trimer.  
 EXAMPLE XX A solution of 5 mmoles of cyclohexane-1,4-dione in 30 ml of propionic acid was placed in a 100 ml Erlenmeyer flask containing a spinbar for magnetic stirring and cooled to just below C by adding powdered dry ice to the solution. To the cooled solution was added with stirring 0.5 ml of a perchloric acid solution, 10% in acetic acid, and 20 mmoles of 1,1 dihydroperoxydicyclohexyl peroxide. The temperature was maintained at 20C for 3 hours and then raised to 0C and maintained for 17 hours. Thereupon, ml of water was added which resulted in the formation of a viscous liquid as the bottom layer. The bottom layer was separated and washed with water and then dissolved in about 20 ml of methanol. The solution was kept for 7 days at 0C, after this time crystals separated; they were filtered, washed with methanol, recrystallized from acetone to give a yield of 0.48 grams, 13 per cent yield, mp. C. The product, tetracyclohexylidene -l,4-cyclohexylidene, was checked by elemental analysis. molecular weight determination in benzene and by infrared spectrum.  
  Thus, with the process of the present invention one is able to produce mixed tricycloalkylidene peroxides in high yields as well as the mixed dicycloalkylidene peroxides in high yields within a short reaction time employing solid ketones. Also, it was not necessary to employ an excess of the ketones. The procedure itself is straight-forward and not complicated. Further, the process of this invention has produced novel dimeric peroxides.  
 What is claimed is:  
  l. A method for preparing nonsymmetrical trimeric peroxides of the formula:  
  lZ X C O 0 0 l (Cl-l K V C x R (C 2) wherein:  
 x and y are different and are positive integers of from 4 to 17 R is hydrogen or methoxy which comprises reacting 1,1-dihydroperoxydicyclic peroxide of the formula:  
  C (i) OOH d OOH (CH )x with a cyclic ketone of the formula:  
 2. The method of claim 1 wherein R is hydrogen.  
  3. The method of claim 1 wherein the strong acid catalyst is selected from the group consisting of perchloric, hydrochloric, sulfuric, nitric and p-toluene sulfonic acids.  
  4. The method of claim 1 wherein the temperature is about -20C.  
  5. The method of claim 1 wherein the ratio of peroxide to concentrated acid catalyst is from about 200 mmolezml to about 200 mm0le:lOO/ml.  
  6. The method of claim 1 wherein the ratio of peroxide to acid solvent is from about 50 mmolezlO ml to about 50 mmolez3000 ml.  
 7. The method of claim 1 wherein the acid solvent is propionic acid.