Patented Feb. 26, 1946 2,395,455 UNITED STATES PATENT OFFICE 2,395,455 . DHYDRONoRPoLYCYCLOPENTADIENYL SOBOCYANATES Herman A. Bruson, Philadelphia, Pa., assignor to The Resinous Products & Chemical Company, Philadelphia, Pa., a corporation of Delaware No Drawing. Application January 13, 1945, Seria No. 57239 9 Claims (CL 260-454) This invention relates to addition-rearrange endomethylene group and possess two double. ment products of nascent thiocyanic acid (HSCN) bonds, only one of which, however, responds to and polycyclopentadienes having two double the reaction with thiocyanic acid even when in bonds and one to four endomethylene cycles per excess. Individual, relatively pure, polycyclo molecule. It further relates to a method for the 5 pentadienes may be used or mixtures of these preparation of these new products. hydrocarbons. In accordance with the disclosure of the pres The reaction of polycyclopentadienes and nas ent application, which is a continuation-in-part cent thiocyanic acid takes place particularly rap of application Serial No. 476,646, filed February idly in the presence of water-at temperatures 20, 1943, thiocyanic acid is reacted in the pres 0 of about 60° C. to about 110° C., although some ence of water with polycyclopentadienes having what lower and higher temperatures may be used. the formula: In the preferred temperature range little, if any, polymerization of thiocyanic acid occurs. This acid is generated in situ from a thiocyanate salt 5 and a strong, non-Oxidizing acid which is strong er than thiocyanic acid. The reaction between polycyclopentadiene and thiocyanic acid is carried out by mixing a salt of thiocyanic acid, water, and polycyclopentadi so ene, heating the mixture to a reacting tempera ture, preferably 60° C. to 110° C., and, while the mixture is stirred rapidly, gradually adding an wherein 72 is zero or a Small integer, such as 1, acid, preferably a mineral acid such as sulfuric 2, or 3. The polycyclopentadiene adds thiocyanic or hydrochloric. The strong acid momentarily acid, and, at the same time, a rearrangement. 25 liberates thiocyanic acid which reacts at Once takes place to form a new type of ring system with the polycyclopentadiene. At the same time, Containing one double bond in a terminal five a rearrangement takes place to yield isothiocy membered cycle. This new ring system is here anodihydromorpolycyclopentadiene. designated as the norpolycyclopentadiene sys These new compounds may be represented by tem. The new addition-rearrangement products 80 the general formula: are primarily unsaturated isothiocyanates with the possible presence of small amounts of thio cyanates. The character of the group added, C ch contrary to what was expected, is an -N-a-C==S group as demonstrated by the reaction of the new addition-rearrangement products with an 35 ? li N" monia and amines which form thiou reas there B with . The isothiocyanates of this invention are --Jit H. capable of undergoing further reaction at the ole finic linkage of the terminal five-membered cycle - a to give new saturated cyclic Compounds. The new isothiocyanodihydromorpolycyclopentadienes may wherein n is a number from zero to three, in add chlorine, bromine, iodine chloride, iodine clusive, and C3H4 is a propenylene group which bromide, thiocyanogen, hydrogen, etc., to this 45 in conjunction with the adjoining carbon atoms residual bond. forms a cyclopentenO group. typical of the polycyclopentadienes having , While any salt of thiocyanic acid can be used, two double bonds per molecule which may be used it is advantageous to use water-soluble salts, such for the purposes of this invention are dicyclo as ammonium thiocyanate, sodium thiocyanate, pentadiene, tricyclopentadiene, tetracyclopenta 50 potassium thiocyanate, calcium thiocyanate, and diene, pentacyclopentadiene, and homologues, the like. It is desirable to liberate thiocyanic acid isomers, and mixtures thereof. These hydrocar from these salts by the use of approximately bons are crystalline solids obtainable by heating equivalent proportions of strong raineral acid. cyclopentadiene at 150-200 C. in a closed ves The following examples illustrate this invenir sel. They contain one to four cycles having an is tion, the parts being by weight. 2 2,395,455 f . Eacample 1 The product consists primarily of the isothio A mixture of 132 parts of dicyclopentadiene, 75 cyanate having the probable formula: parts of water, and 76 parts of ammonium thio C CH CH cyanate is rapidly stirred and heated under a reflux condenser at 90°-95 C. To the hot, stirred 5 of ? f Yoh solution, 100 parts of concentrated hydrochloric acid (37%) is added dropwise during the course of one hour while the reaction temperature is elt1 NfI . maintained at 90°-95° C. The mixture is then O when this product is crystallized from ethanol, heated for three hours longer at 90-95 C., fl white, fluffy, needle crystals, melting at 66-67 C., tered hot by suction, and allowed to separate into are obtained. These dissolve in kerosene and layers. The oil layer of the clear filtrate is sep other organic solvents to yield a powerful insec arated, then washed with water, and distilled in ticidal spray against flies, mosquitoes, roaches, vacuo. The thiocyanic acid addition-rearrange 15 etc. The sprays made from this isothiocyanate ment product of dicyclopentadiene distils over and also other isothiocyanates of this invention between 127° and 132° C. at 2 mm. absolute pres are exceptionally free from possibly objection sure of mercury as a pale yellow oil having a characteristic faint thiocyanate-like odor. The able odor and from irritation. r yield is 120 parts. Upon redistillation it boils at Eacample 4 140°-142° C./6 mm. and possesses the probable 20 One hundred thirty-two parts of dicyclopenta formula: diene is mixed with 264 parts of tetracyclopenta B CH diene, 225 parts of water, and 152 parts of am monium thiocyanate. The mixture is stirred and 25 heated under reflux to 95-100° C., and 200 parts ca if " of concentrated 37% hydrochloric acid added dropwise thereto during the course of two hours. chill. The mixture is stirred and heated for an addi tional two hours at 95-100° C., then mixed with It is readily soluble in kerosene and such solutions 30 an equal volume of toluene, and filtered hot by may be used for killing flies, mosquitoes, bed suction. The oil layer of the filtrate is separated, bugs, and other soft-bodied insects. washed, and distilled under reduced pressure at The product of Example 1 when boiled with 1 mm. until the vapor temperature reaches 200 ammonium hydroxide solution yields the crystal C/2 mm. Dihydronordicyclopentadienyl isothio line thiourea: cyanate is obtained in a yield of 128 parts, boiling S at 127°-130° C./1 mm. Dihydron Ortetracyclo CH-NH--NH, pentadienyl isothiocyanate, weighing 250 parts, which has a melting point of 197°C. It also gives, cannot be distilled at this pressure without de upon being boiled with acetic acid, the corre composition. It is obtained as a dark red oil. sponding amide, C10H13NHCOCH3, having a melt 40 In the same manner, dihydronorpentacyclo ing point of 129°-130° C. pentadienyl isothiocyanate can be obtained as a The product of this example is soluble in lubri dark red oil by reacting pentacyclopentadiene cating oil and may be added thereto to give better with nascent thiocyanic acid. lubrication under extreme preSSureS. Although in the above examples practically 45 pure polycyclopentadienes have been used, the Eacample 2 process shown may also be applied to mixtures of hydrocarbons which contain 5% or more of the To a mixture of 132 parts of dicyclopentadiene, polycyclopentadienes having two double bonds per 100 parts of water, and 81 parts of sodium thio molecule, such as are obtained in the thermal cyanate heated to 99 C. and rapidly stirred un 50 cracking of petroleum or in the manufacture of der reflux, there is gradually added 135 parts of Water gas. The reaction. Of the polycyclopenta 37% sulfuric acid during the course of thirty-five dienes provides a new means for separating the minutes. The mixture is then heated and stirred components of mixtures of unsaturated hydro for one-half hour longer at 99 C. and filtered carbons and gives new utility to such products. hot by suction. The oil layer of the filtrate is 55 I claim: separated, washed with water, and distilled in 1. The addition-rearrangement product of One vacuo. The distillate is dihydronordicyclopenta mol of nascent thiocyanic acid and One mol of diene isothiocyanate, identical with that obtained a crystalline polycyclopentadiene having two in Example 1, in a yield of 100 parts. double bonds and one to four endomethylene Eacample 3 60 cycles per molecule, said acid being formed in the presence of said polycyclopentadiene in an Fifty parts of concentrated hydrochloric acid aqueous bath at 60° C. to 100° C. and said product (37% strength) is added dropwise during the being a dihydronor polycyclopentadienyl isothio course of twenty-five minutes to a well-stirred cyanate. - mixture of 99 parts of tricyclopentadiene, 40 parts 65 2. The addition-rearrangement product of one of water, and 38 parts of ammonium thiocyanate, mol of nascent thiocyanic acid and One mol of which is maintained at 95-99 C. under a reflux dicyclopentadiene having two double bonds and condenser. The mixture is then stirred for One one endomethylene cycle per molecule, said acid half hour longer at 95-99. C., and is filtered hot being formed in the presence of the dicyclopenta by suction. The oil layer of the filtrate is Sep 70 diene in an aqueous bath at 60° C. to 100° C. and arated, washed and distilled in vacuo. said product being dihydronordicyclopentadienyl The addition-rearrangement of HSCN and tri isothiocyanate. cyclopentadiene distils over between 188 and 190° 3.