Патент USA US2134102код для вставки
:Patented Oct.25, 1938 j 2,134,102 ' UNITED STATES PvA'T-E’NT: OFFICE‘? 27,134,102 ' ' ' > pnnrnnoonnoams'rrowor 1,1,2-rm cnLonrnoPANn Oliver W. Cass, lViagai-a Falls, N. Y., assignor to ' E. ‘I. du Pont de Nemours & Company, Wil mington,‘ DeL, a corporation of Delaware No Drawing. Application May 13, 1935, Serial No: 21,300. _ 5 Claims. (01. mill-654) I, This application relates to the preparation of unsaturated chlorhydrocarbon derivatives from 'CE=CH.CHC12 and CHa.CCl_=CHCl are not present in any ap- ‘ _ ‘ , saturated chlorhydrocarbons by treatment with a basic material. More particularly it relates .pre‘ciable amounts and that. 1,1-dichlorpropene— ' 5 to the preparation oi, 1,1-dichlorpropene~l, . CHa.CH=QCh. produced‘ in practically quantitative yields. by reacting 1,1,2 trichlorpropane, CHaCI-ICLCHCII. 10 with a base.‘ 1, the isomer which from theoretical considera- ‘5 , tions would be believed leastlikely to result, is I . have found that, the 1,1-dichlorpropene-2 and the 1,2-dichlorpropene-1, isomers arenot pro , In a copending patent application, Ser. No. 19,954 ?ied May 6, 1935 by Arthur A. Levine and Oliver W. Cass, a process is disclosed for the 15 preparation of isomeric mixtures consisting es-' sentially oi 1,1,2 triehlorpropane and 1,2,3 tri duced since they are not fiound in ‘recoverable 1o amounts in the‘ reaction product and the 1,1‘ chlorpropene-l isomer is formed in yields which are' normally well over 90%. '_ As a basic material I have used aqueous solu tions of sodium and potassium hydroxide vand 15 aqueous solutions of the alkali earth metal hy chlorpropane by chlorinating propylene dichlo "droxides such as calcium hydroxide. Any basic ride. ‘In that application separation of the two material is suitable. Thus I have used with isomers by distillation and condensation is also complete success, alcoholic solutions of caustic ” disclosed. This application relates to the ‘fur-. soda and caustic potash. I prefer,‘ however, ior 20 ther treatment oi'the 1,1,2 trichlorpropane iso mer to prepare a chemical compound which is valuable for various purposes. , - The compound 1,1,2 trichlorpropane,’ most purposes. to use one of the relatively less' expensive alkali metal bases dissolved in some suitable solvent such as alcohol or water. Bolu-4 tions of soda ash (sodium carbonate) in various ‘ media will also be iound'entirely satisfactory for 25 ” - cmoncrcncn. ' ‘ the purposes oi’ the process. when pure, is a colorless liquid having an at mospheric boiling pointooi approximately 132' C. One of the objects. oi.’ this invention is to ” react this liquid with'basic material at a tem perature belowkthe boiling point of the trichlor- - ' ' _ While the process of this reaction'is best car ried out in the liquid-‘phase, it is also possible to remove an atom of chlorine and one atom 01' hydrogen from 1,1,2 trichlorpropane and con- 30 ' vert it to an unsaturated compound by the use propane so ~that an atom of hydrogen and one of a gas phase reaction. Thus by vaporizing the .0! chlorine are split oil, thereby resulting in an . 1,1,2 ' trichlorpropane and passing the vapors unsaturated compound having one atom less of 35 chlorine. 7 - . -. . Prom considerations of theoretical chemistry, any one of three isomers might result by the over a catalyst comprising any .01’ the common hydrogen chloride-removing catalysts. such as 35, barium chloride on‘ charcoal, commercially im portant yields of 1,1-dichlorpropene-l have been removal oi.’ hydrogen chloride from the trichlor- ' obtained. Other suitable catalysts are the hal - ides particularly the chlorides of various metals Propane. These threeisomers are such as those of Ni, 'Cu,‘Pb, Cd and Fe. When 40 ‘°' - ' cm=cn.cnc1i: [ using barium chloride on charcoal the process-is‘ cmcc1=cnc1. ' ' ' ,and 'cnscn=c'c1=. 45 . . v A consideration of chemical0 principles would ' best carried out at an elevated temperature of about 300° C. or ‘one within the’ temperature range 250 to 350° C. vIn this reaction, as con; trasted with the liquid phase reaction,‘the chlo- 45 ' rine is removed as hydrogen chloride and not as, a salt of the base, as when utilizing a liquid also indicate that presumably‘ a mixturev of all three isomers in various proportions and amounts might result. Of the three possible But little need be said about the precise de 50 isomers, 1,1-dichlorpropene-1, CHaCH=CCh, is tails of the process, other than that it is pre- so _ the one which might be, considered'least likely ierred that it becarried out in the ‘liquid phase. to result since it is a derivative of methyl ketene, The ‘1,1,2 trichlorpropane is introduced into a CH:.CH=CO, which“ is an extremely ' unstable vessel containing a ‘strong solution of the base phasev process. compound. Surprisingly enough, however, ithas “ been discovered that the isomers \. ' _ : - ‘ - dissolved in a suitable solvent such as water or. ~ alcohol, While the reaction will proceed at room?“ 8,184,108 temperature, it is preferable to maintain a some what elevated temperature,"one somewhere be tween the boiling point of 1,1-dichlorpropene-1 . (which is 77-78° C.) and‘ the boiling point of the 1,1,2 trichlorpropane (132° 0.). However, since 5 liter ?ask."I‘he ?ask was equipped with a stirrer and a re?ux condenser. Into the ?ask 1475 grams of. 1,1,2 trichlorpropane was then introduced. The mixture was thoroughly stirred and heated until an oil began to re?ux back in the con pene-l-will steam distill at a temperature below denser, the mixture in the reaction vessel being 77° C., it is not necessary to maintain a temper- ‘ maintained at a temperature of about 75° C. ature that high. 'Ihere \are two procedures of The elevated temperature in the reaction vessel 10 value in carrying out this liquid phase reaction. was maintained for three hours during which A re?ux condenser may be attached to the vessel period the mixture was stirred constantly. At in which the reaction is carried out, in which the end of this period the oil was separated from there is water present and ‘the 1,1-dichlorpro case the 1,.l-dichlorpropene-i, which is distilled off, will be condensed and ?ow back into the ves ll sel. Or, it is possible to attach to the vessel a fractionation column in which ‘the 1,1-dichlor propene-l will be distilled o?', ‘condensed, and recovered as a liquid outside of the reaction vessel. Yields of about the same uniformly high the slightly basic aqueous solution, dried, and carefully fractionated. ' The product was 953 grams of 1,1-dichlor propene-l, which has a boiling point of about “Fl-78° C. 94 grams of the residue consisted of unreacted 1,1,2 trichlorpropane. Based upon the quantity of sodium hydroxide consumed, the yield of 1,1 chlorpropene-i was 94% theoretical. 20 Example 2 _ In practice, as I have indicated, the 1,1,2 tri-v chlorpropa-ne is preferably added to the basic In these operations a ?ask equipped with a percentages are obtained by the use of either vmethod. . material dissolved in a solvent. Heat is then stirrer and “a short fractionation column was applied and the mixture is thoroughly stirred. used. .The same weights of materials indicated The elevated temperature is maintained for about in Example 1 were reacted, i. e. 400 grams of 95% three hours during which time the agitationv is sodium hydroxide in 2500v cc. of water and 1475 continuous. At the end of this period, if a re?ux - grams of the trichlorpropane. A condenser was condenser has been used, the oil may be readily placed incommunication with the fractionation separated from the basic material since it will column so that material passing thru the column rise to the top of the vessel. On the other hand, - and condenser would flow into‘ a receiving vessel. ‘ if a fractionation column has been used, the The reaction vessel and its contents were heat 1,1-dichlorpropene-l will be found in the re ed with constant stirring to a temperature “of ceiver attached to the condenser of the frac about 78°-85° C. at which temperature liquid ‘ionation column. I . began to pass through the fractionation column 1,i,-dichlorpropene-1 is readilyseparated from and condenser to the receiving vessel. After‘ unreacted 1,1,2 trichlorpropane and any other ‘about three hours no more oily material re by-products. in the reaction mixture since it has mained in the reaction vessel. The oil was sepa a boiling point of 77-78. C. while the boiling point rated from the aqueousj layer in the receiver, of 1,1,2 trichlorpropane‘is 132' C. High yields dried and fractionated. 40 are obtained by the process, the yields being in The product consisted of 908 grams of 1,1-di the neighborhood of 90% or over. 1 , chlorpropene-l boiling at 77-78° C. and 114 grams The reaction occurring, using sodium hy of unreacted 1,1,2 trichlorpropane. The yield of 1,1-dlchlorpropene-l, based upon the amount of sodium hydroxide consumed, was 89% of the - 'droxide as a typical basic material, may be ex pressed as follows: CKCHCl.CHCls+NaOH->CH:CH= theoretical. ‘ CCla-i-NaCl-i-HaO When using a catalytic material such as BaCl: on a charcoal carrier, the reaction occurring is probably as follows: cmcnorcnmbcmcn=dcn+xc1 It is thus evident that a saturated chlorinated 55 hydrocarbon is converted into an unsaturated chlorinated hydrocarbon containing one atom - In this example the ‘reaction was carried out at room temperature and without external heat ing. A solution of 56 grams of potassium hy droxide in 800 cc. of ethyl alcohol was placed in a 1-liter ?ask. To the potassium hydroxide was then added 147.5 grams of 1,1,2 trichlorpropane. A rise in temperature of the ?ask contents was 56 evident 'at once and a white'precipitate of po less of chlorine by the removal of hydrogen chlo tassium chloride immediately formed. ride in the process disclosed. The precipitated potassium chloride was re moved by ?ltration and the alcoholic filtrate was diluted with water. The oily layer which sepa rated was removed, washed with water, dried and distilled. A fraction of 51 grams boiling at 75-85° C. was secured. The greater portion of As previously sug- I gested, it is indeed surprising that the 1,1-di chlorpropene-l isomer is produced in substantial quantitative yields and that the two other isomers CH==CH.CHC12 and CH.1.CC1=CKCi are practi cally completely absent. Moreover ‘when it is considered that the 1,1-dichlorpropene-1 isomer CH.1.CH=CClz is a derivative of methyl ketene, CH1.CH=CO, and would normally be expected propane is indeed remarkable. ' As ‘illustrative examples of the process the fol lowing may be given: ~ ~ this fraction was 1,1-dichlorpropene-l, boiling at 77.5. C. The yield was 67% ‘of the theoreti cal based on the quantity of potassium hydroxide used. up in the reaction. to be unstable, the preparation of this product by removal of hydrogen chloride from trichlor 70 = Emmple 3‘ Example 4 In this example 590 grams of 1,1,2 trichlorpro 70 pane were stirred for six hours in a flask fitted with a re?ux condenser vat a temperature of 85° C. with a 20% excessv of a 20% calcium oxide A solution of 400 or‘ 95% sodium hy-_ suspension in water. At ‘the end of this period droxide and 2500 cc. of water was 91min a the oil was removed by steam distillation, sepa 2,134,102 rated from the aqueous layer, dried and frac ting 01! hydrogen chloride irom the trichlorpro tionated. pane by a catalytic process utilizing a hydrogen ‘ \ The product consisted 01-195 gramsof 1,1-di chlorpropene-l and 253 grams of unreacted 1,1,2 ed to the speci?c times, temperatures, conditions, pene-l, based upon the amount of 1,1,2 trichlor chemical agents,'or amounts which have been dis closed as illustrative in the preceding typical examples. Various modi?cations of the inven tion may come within its purview and the-scope theoretical. ‘ . Example 5 In this example hydrogen chloride was re moved from the 1,1,2 trichlorpropane by the use i of the hydrogenchloride-removing catalyst bari um chloride. A tube was packed with charcoal on which the 15 barium chloride was retained. The tube was ?tted at the upper end with an inlet bulb which could be ?lled with the trlchlorpropane. A stop cock at the lower end of this bulb could be ad 20 chloride-removing catalyst. The invention is one of broad general utility and is not to be restrict 'trichlorpropane. ‘ The yield of 1,1-dichlorpro propane used up in the reaction was 77% of the 10 3 , justed to regulate the ?ow of the liquid through the tube. , . ' The tube was heated to a temperature of 300 350° C. and the 1,1,2 trichlorpropane permitted to ?ow at a relatively slow rate through the tube. Hydrogen chloride gas was evolved and passed. 25 out through a ventin the upper end of the col umn. The lower end of the tube, which was in _ communication with a condenser, served to col lect the reaction product. _ In the condenser at the lower end of the heat 30 ed tube an oil separated which was washed with thereofis to be determined solely in‘ accordance 10 with the appended claims. I claim: ' I 1. A process of preparing 1,1-dichlorpropene-1 which comprises reacting 1,1,2 trichlorpropane with a basic compound of a metal of the group 15 consisting of the alkali metals and the alkaline earth metals. I , - 2. A process of preparing 1,1-dichlorpropene-1 which comprises reacting 1,1,2 trichlor'propane with a basic compound of a metal of the group 20 consisting of the alkali metals and the alkaline earth metals at a temperature below the boiling point of 1,1,2 trichlorpropane. 3. A process for “preparing 1,1-dichlorpropene-1 whichv comprises reacting 1,1,2 trichlorpropane 25 in the liquid phase with a basic compound of a metal of the group consisting of the alkali metals and the alkaline earth metals. 4. A process for preparing 1,1-dichlorpropene-1 which comprises reacting 1,1,2 trlchlorpropane in 30 the liquid state with a solution of sodium hy water and distilled. From this product 30 grams of 1,1-dichlorpropene-1 boiling at a temperature droxide. 5. A process for preparing 1,1-dichlorpropene-1 of 77-78 C. was obtained. The isomers 1,1 di-‘ which comprises reacting 1,1,2 trichlorpropane in chlorpropene-Z and 1,2 dichlorpropene-1 'could the liquid state at an elevated temperature with 35 35 not be found in the reaction product. a basic compound of a metal of the group con It is thus evident that the invention resides in sisting of the alkali metals and the alkaline earth the prepaartion of 1,1 dichlorpropene-i in sub stantially quantitative yields by reacting 1,1,2 tri chlorpropane with a basic material or by split metals dissolved in a suitable solvent. OLIVER W. CASS’.