US2864867A - Condensation reactions - Google Patents

Description

United States Patent CONDENSATION REACTIONS Company, St. Paul, Minn., a corporation of Delaware No Drawing. Application July 12, 1955 Serial N 0. 521,639

14 Claims. (Cl. 260-609) This invention relates to reactions of thiols with highly fluorinated olefins and includes reactions under free radical conditions, ionic conditions, and also vinyl replacement reactions.

In accordance With the process of the present invention, monoand polymercaptans having 1 to about 16' carbon atoms are reacted with polyhalogenated ethylenically unsaturated compounds having from 3 to about 12' carbon atoms. The invention also includes the use of perhalogenated ethylenically unsaturated compounds and, in both cases, all of the halogen atoms of the ethylenically unsaturated compounds are chlorine or fluorine, and at least half of the halogen atoms are fluorine.

Exemplary of the alkyl mercaptans which may be used are those having the formulae, CH (CH SH, in which n is an integer from 1 to 17; HS(CH SH, in which n is an integer from 2 to 12;

HS CH CHSI-I CH SH in which m and n are integers from I to 6;

HS(CH2)MCH(OH2)1|SH CHzSH in which m and n are integers from 1 to 6; and

[(CH2)12SH]4 in which n is an integer from 1 too.

Among the aryl mercaptans which may be used are: thiophenol, the thiocresols, alpha and beta thionaphthol and compounds having the formulae:

HS SH @Q HSHzC SH SH and Among the polyhalogenated and perhalogenated ethylenically unsaturated compounds which may be used are: hexafluoropropene, perfluoro-1,5-hexadiene, 4-chlo'ro-l',1,

ice?

2,3,3,4-hexafluoro-l-butene, and compounds having such formulas as:

CF =CF(CF CF=CF(CF ),,CF=CF and CF =CC1(CF ),,,CC1=CC1(CF ),,CF=CF in which in and n are integers from 1 to 5; and

C FgOFz-C F=C F2 0 F2-C F-O F=C F2 and the like.

Polyhalogenated olefins having some hydrogen substituents may also be used provided the majority of the carbon atoms have at least 1 fluorine or chlorine substituent attached thereto. In a preferred embodiment of the invention, the olefins are perhalogenated.

When the reaction of the present invention is conducted under free radical conditions, these conditions may be obtained by the use of ultraviolet illumination or by the use of a catalyst such as benzoyl peroxide.

The molar ratio of monoolefin to mercaptan may be from about 1 to 1 to about 1 to 10, preferably from about 1 to 1 to l to 2. When dior triolefius are used, the

ratio'is correspondingly increased in favor of the mer captan, and when polymercaptans are used, the ratio is correspondingly increased in favor of the olefin. The time of reaction may be from a few minutes to about 10 hours, and the temperature may be in the range of about 25 C. to about 150 C.

The formation of reaction products becomes increasingly difiicult as the molecular Weight of the olefin increases; for example, the reaction of perfluor0-1,5-hexa diene and excess thiophenol produced only a small yield of product.

The reaction of thiols with fluoroolefins may also be effected under base catalyzed or ionic conditions, and these conditions may be obtained by the use of such materials as benzyltrimethylammonium hydroxide, sodium and potassium hydroxides, carbonates, and other bases capable of reacting with the --CH groups of thiols to-form salts.

The product obtained may be controlled by theratio of reactants, as the presence of excess olefin favors the formation of a mono-substituted product, While the presence of excess mercaptan favors the formation of the disubstitution product. This is shown by the following equations in which X and X are chlorine or fluorine, R

and R are chlorine, fluorine or perhalogenated alkyl rad- One mole'or less (2) X X1 excess R25 SR The first step proceeds more easily than does the second and produces a good yield of pure product based upon mercaptan. The secondstep requires more, vigorous conditions or a longer reaction time.

The reaction of thiophenol with perfluo'ro LS-hexadiene in the presence of benzyltrimethylammonium hydroxide occurs very readily and results in complete neutralization of the added base with formation of. excess Patented Dec, 16,- 1958,

acid and a small yield of product. This result suggests that replacement of vinylic fluorine occurs as the primary reaction.

A similar reactivity is observed with perfluoropropene and dodecyl mercaptan. Complete consumption of the mercaptan is achieved, and a 97 percent yield of crude product is isolated. The structure of the product is indicated as CH (CH SCF=CFCF by analysis and its infrared spectrum, and the monoreplacement product was found qualitatively to react to completion with a second mole of mercaptan.

The reaction products of the invention are useful as additives to lubricating oils, insecticides, herbicides, and as chemical intermediates in the formation of other novel and useful compositions of matter.

The invention will be further illustrated by reference to the following specific examples:

EXAMPLE 1 Reaction of thiophenol with perfluoro- 1,5-hexadiene A Pyrex glass ampoule was charged with a mixture of 27 grams (0.10 mole) of (CF =CFCF 22 grams (0.20) mole of C H SH and 0.13 gram of benzoyl peroxide. The olefin and mercaptan were not very soluble in each other. The 2 layer system was heated in an oil bath at 65-70" C. for two and one-half hours, but no change was observed in the size of either layer. The ampoule was finally recharged with 0.26 gram of benzoyl peroxide and placed in a rocker shaker for seventeen and one-half hours at 83 C. A very small change was noted in the size of the layers. The ampoule was opened and the mixture heated to drive oil 24 grams of unreacted olefin. The remainder of the liquid (24 grams) had the characteristic smell of C H SH. It was washed with 10 percent NaOH to remove the mercaptan, leaving a residue of 14 grams. This was distilled to yield:

Grams (1) B. P. 77.5-80 C./727 mm 2 (2) B. P. 38-80 C./0.5 mm 3 (3) Residue 9 Fraction 1 was saturated to 2 percent KMnO, and a sodium fusion showed that it did not contain fluorine or sulfur. Fraction 2 reacted with a 5 percent solution of bromine in carbon tetrachloride to a moderate extent and reduced 2 percent KMnO, only at the boiling point of the acetone solvent Sodium fusion showed that this fraction contained fluorine and sulfur. Presumably it consisted of a small yield of replacement products.

EXAMPLE 2 Reaction of thiophenol with 4-chlor0-1,1,2,3,3,4-hexafluoro-l butene A homogeneous mixture of 25 grams (0.12 mole) of CF =CFCF CHClF, 11 grams (0.10 mole) of C H SH and 0.24 gram (0.001 mole) of benzoyl peroxide was placed in a Pyrex glass ampoule and irradiated by 8 U. V. lamps for 8 hours and then opened. The odor of the mercaptan was still quite noticeable. An additional 0.24 gram of benzoyl peroxide was added, the ampoule was rescaled and heated at 90100 C. for 2 hours in the rocker shaker. The ampoule was opened and the odor of thiophenol was still quite noticeable. Heating of the ampoule in an oil bath removed 15 grams of unreacted olefin. The residue was washed in NaOH solution but only a few drops of insoluble material were found indicating that no more than a small amount of addition could have occurred.

EXAMPLE 3 Reaction of thiophenol with perflu0ro-1,5-hexadiene A mixture of 30 grams (0.11 mole) of C F and 8 ml. (0.020 mole) of benzyltrimethylammonium hydroxide added as a 40 percent aqueous solution was placed in a 100 ml. pear-shaped flask fitted with a water cooled con- Grams (1) B. P. 508S C./0.S mm. 9 (2) Residue 4.5

Fraction 1 had a pleasant odor and was unsaturated to potassium permanganate. The residue was very viscous at room temperature.

Acidification of the NaOI-l used for washing produced 10 grams of unreacted thiophenol. Titration of the acidic aqueous layer removed from the pear flask showed that 0.0191 mole of acid was present; the total acid produced amounted to 0.0191+0.020 or 0.039 mole. Obviously, the product formed was a mixture.

An infrared spectrum of fraction 1 showed major absorption peaks at 5.61,a, 6.80 1 and 697a. The peak at 5.61 can be attributed to I C=C 2 REPLACEMENT OF VINYL HALOGEN IN FLUOROOLE- FINS BY REACTION WITH BIERCAPTANS EXAMPLE 4 Reaction of dodecyl mercaptan and hexafluoropropene A mixture of 40 grams (0.20 mole) of dodecyl mercaptan, 28 grams (0.20 mole) of potassium carbonate, 200 ml. of acetone, and 10 ml. of water were placed in a 500 ml. flask. The propene, 49 grams, (0.33 mole) was rapidly condensed into the system during ten minutes and resulted in a pot temperature of 10 C. at reflux. The

temperature rose slowly and reflux ceased after four hours. Considerable mercaptan was still present at this point and an additional 10 ml. of water and 14 grams of potassium carbonate were added. A silver nitrate test for the presence of RSH was negative eight hours later, and the carbonate salts contained considerable F". The reaction mixture was drowned in water, and the organic product was washed twice, and dried over magnesium sulfate to yield 66 grams of product. This was pumped at a pressure of 5 mm. at room temperature for one hour to remove 2 grams of C 1 The remaining 64 grams corresponded to a 97 percent yield. The cis-trans mixture appeared to be essentially the unsaturated sulfide, since a freezing point of 35 to 40 C. was obtained without further purification.

For physical properties 54 grams of the sulfide were distilled from a sidearm flask to yield:

(1) B. P. 128130 C./4 111111., 18 grams, 11 1.4212 (2) B. P. l30131 C./4 mm., 24 grams n 1.4200 (3) Residue, 12 grams, n 1.4210

Properties of fraction 2 were: B. P. 13013l C./4 mm; 11 1.4200; (1 3, 1.0654; F. P. 35.3 to 42.0 C. Calculated for C H F S: MR 78.9; S, 9.62 percent. Found: MR 39.7; S, 9.66 percent.

An infrared spectrum of the product gave a weak absorption peak at 5.99; and none at 5.55-5.61 which is characteristic of CF=CF--. On this basis and by analogy with the orientation shown for addition reactions the structure was assigned as RSCF=CFCF (R==dodecyl').

A qualitative test tube reaction showed that this sulfide would react with a second mole of mercaptan' in apparently high yield since all the mercaptan was cons'umed.

It will be obvious to those skilled in the art that many modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications.

I claim:

1. A process for the replacement of a vinylic halogen of an unsaturated halocarbon which comprises reacting in the temperature range of 25 to 150 C. a compound selected from the group consisting of monoand polymercaptans having from one to about 16 carbon atoms with a polyhalogenated ethylenically unsaturated compound having from 3 to about 12 carbon atoms and having at least one halogen atom bonded to each of the doubly bonded carbon atoms and in which the halogen atoms are selected from the group consisting of chlorine an'd fluorine, at least half of the halogen atoms being fluorine.

2. A process for the replacement of a vinylic halogen of an unsaturated halocarbon which comprises reacting in the temperature range of 25 to 150 C. a compound selected from the group consisting of monoand polymercaptans having from one to about 16 carbon atoms with a perhalogenated ethylenically unsaturated compound having from 3 to about 12 carbon atoms and in which the halogen atoms are selected from the group consisting of chlorine and fluorine, at least half of the halogen atoms being fluorine.

3. A process according to claim 2 in which the reaction is conducted under free radical conditions.

4. A process according to claim 2 in which the reaction is conducted under ionic conditions.

5. A process according to claim 2 in which the reaction is a vinyl fluoride replacement reaction conducted in the presence of a solvent and a base.

6. A process for the replacement of a vinylic halogen of an unsaturated halocarbon which comprises reacting in the temperature range of 25 to 150 C. a compound selected from the group consisting of monoand polymercaptan's having from one to about 16 carbon atoms with a compound having the formula,

in which X and X are selected from the group consisting of chlorine and fluorine, R and R are selected from the group consisting of chlorine, fluorine, and polyhalogenated radicals in which all the halogens are fluorine; the compound containing not in excess of about 12 carbon atoms, at least one of R and R being a polyhalogenated radical, and at least half of the total halogen atoms present being fluorine.

7. A process for the replacement of a vinylic halogen of an unsaturated halocarbon which comprises reacting in the temperature range of 25 to 150 C. a compound selected from the group consisting of monoand polymercaptans having from one to about 16 carbon atoms with a compound having the formula,

ganic radical in which all the halogens are fluorine; the compound containing not in excess of about 12 carbon atoms and at least half of the total halogen atoms present being fluorine.

8. A process for the replacement of a vinylichalogen of an unsaturated halocarbon which comprises reacting in the temperature range of 25 to 150 C. a compound selected from the group consisting of monoand polymercaptans having from one to about 16 carbon atoms with bon atoms, at least one of R and R being a perhalogenated radical, and at least half of the total halogen atoms present being fluorine.

9. A process for the replacement of a vinylic halogen of an unsaturated halocarbon which comprises reacting in the temperature range of to 150 C. a compound selected from the group consisting of monoand polymercaptans having from one to about 16 carbon atoms with a compound havin'g the formula,

FC=( -R1 in which X'and X are selected from the group consisting of chlorine and fluorine, R is a polyhalogenated organic radical in which all the halogens are fluorine; the compound containing not in excess of about 12 carbon atoms and at least half of the total halogen atoms present being fluorine.

10. Compounds having the formula,

in which n is an integer from 1 to 16.

11. A compound having the formula,

12. A process for the replacement of a vinylic halogen of an unsaturated perhaloolefin which comprises reacting an alkyl mercaptan having from 1 to 16 carbon atoms with an ethylenically unsaturated perhaloolefin in which the halogens are selected from the group consisting of fluorine and chlorine and in which said perhaloolefin contains from 3 to 12 carbon atoms under conditions of temperature of about 25 C. to C. and a mole ratio of olefin to mercaptan between about 1:1 and about 1:10. I

13. The process of claim 12 in which said perhaloolefin is a perfiuoromonoolefin.

14. The process of claim 12 in which said alkyl mercaptan is dodecyl mercaptan and said perhaloolefin is hexafluoropropene.

References Cited in the file of this patent UNITED STATES PATENTS 2,594,935 Ladd et al.. Apr. 29, 1952 2,671,799 Miller Mar. 9, 1954 FOREIGN PATENTS 462,856 Canada Jan. 31, 1950 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION December 16, 1958 Patent N00 2,864,867

William T, Miller It is hereby certified that error appears in the-printed specification of the above "numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 4., line 65,, for "39,,7g" read 7907'; m

Signed and sealed this 5th day of May 1959,

(SEAL) Attest:

KARL H. AXLINE ROBERT C. WATSON Commissioner of Patents Attesting Ofiicer

Claims (2)

1. A PROCESS FOR THE REPLACEMENT OF A VINYLIC HALOGEN OF AN UNSATURATED HALOCARBON WHICH COMPRISES REACTING IN THE TEMPERATURE RANGE OF 25 TO 150*C. A COMPOUND SELECTED FROM THE GROUP CONSISTING OF MONO- AND POLYMERCAPTANS HAVING FROM ONE TO ABOUT 16 CARBON ATOMS WITH POLYHALOGENATED ETHYLENICALLY UNSATURATED COMPOUND HAVING 3 TO ABOUT 12 CARBON ATOMS AND HAVING AT LEAST ONE HALOGEN ATOM BONDED TO EACH OF THE DOUBLY BONDED CARBON ATOMS AND IN WHICH THE HALOGEN ATOMS ARE SELECTED FROM THE GROUP CONSISTING OD CHLORINE AND FLUORINE, AT LEAST HALF OF THE HALOGEN ATOMS BEING FLUORINE.

11. A COMPOUND HAVING THE FORMULA