The Reaction of Alkanols and 1, 1, 2-Trichloro-3, 3, 3-trifluoro-1

Received January 11, 1952. The base-catalyzed reaction of alkanols and l,l,2-trichloro-3,3,3-trifluoro-l-propene was found to yield l-aIkoxy-1,2- dich...
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41 04 [CONTRIBUTION FROM

THE

UNIVERSITY OF COLORADO]

The Reaction of Alkanols and 1,1,2-Trichloro-3,3,3-trifluoro-1-propene' B Y J. D.

PARK,

E. HALPERN AND J. R. LACHER

RECEIVEDJANUARY 11, 1952 The base-catalyzed reaction of alkanols and 1,1,2-trichloro-3,3,3-trifluoro-l-propene was found to yield l-alkoxy-l,2dichIoro-3,3,3-trifluoro-l-propene.The physical properties of the ethyl, propyl and butyl alcohol reaction products are reported along with their magnetic siweptibilities and infrared spectra. A plau.;ihle mechanism is also proposed for the react ion,

The base-catalyzed addition of alkanols to fluori- cated at the top of an energy barrier and the difnated olefins has been previously reported by Park, ference in energy between the activated complex Lacher, et U Z . , ~ - ~ and various mechanisms of reac- and the reactants is the activation energy, we tion were suggested. would expect the more stable activated complex The present work describes the base-catalyzed (I) to have less activation energy than the less staaddition of alkanols to 1,1,2-trichloro-3,3,3-tri-ble complex (11). The reaction should therefore fluoro-1-propene to yield compounds of the type proceed mainly over the smaller energy barrier. CF~-CCI=CCl(OR) and an attempt to explain The addition of the alcohols to the olefin CF3this addition through the use of the activated com- CCl-CC12 could be explained on this basis plex theory. However, this attempted explanation ROH + OH- ---+OR- + H20 does not preclude or eliminate the possibility of CFICCI=CCI~ + (OR)- --+ CFiCCl--CCl>(ORi (1) (2) other explanations. Thus, for CF3CCl-CC12 let us consider the two CF - CCI CC12(OR) + ROH + addition complexes CF3CIICl-CCl2(OR) + OR- ( 3 ) CF3-CCl--CClz(OK)

+

CFJCHCICCI~(OR) base

a11d CFjCCl( OR)-CCli

r

I1

Complex (I) is more stable than complex (11) due to the resonance stabilization arising from hyperconjugation of the fluorine atoms in the CF3 group. Since the activated complex is assumed to be loCF,CCI=CCI(OCH3)

--+ F,CCCl=CCI(OR)

CP~--CCI=CCIIOC~HS) I11

V"

-

uu yJ

I

CF,CCI=CCIIOCpHs)

(4)

Proof of Structure.-The reaction products all showed unsaturation with the usual permanganate test. Chlorine analysis also showed the presence of two chlorine atoms. Thus, the chlorine analysis for the ethyl ether was 34% (theory 34%) which is in agreement with the chlorine content of either of the following compounds CF3C(OCzH~)=CCIz IV

Formula 111 was decided upon after ozonolysis of the product was found to yield CF&OOH and C1COOCzH5which is obtainable only from compound 111. Experimental The synthesis of 1,1,2-trichloro-3,3,3-trifluoro-l-propene was carried out according to the method of Henne, et el.5 TABLE OF

PHYSICAL PROPERTIES

2%

8

Compound CPaCCI-CCl(OCE1~) CF~CCI=CCI(OC2Ha) CFICCI-CCI(OC~H~) CI-JCCl-=CCI(OC+T-IP)

(&0 mm.) 112 126 146 16(1

,P.5

1.3919 1.:1980 1.4098 1 ~1110

Density

Chlorine, % Calcd. Pound

1.47162@ 36.37 1.377418 33.97 1.309112 31.83 29.95 1.?4i32?

36.4 34.0 31.91 30 1

100

75 50 25 n

-I

2

3

4

5

6

7

8

9

ID

II

12

13

1415

TABLE OF MAGNETIC SUSCEPTIBILITIES~ The diamagnetic susceptibilities were measured by the Quincke method using benzene as the standard: x,(benzetie) -0.701 X

Wove Length In Microns.

Fig. 1.-The infrared absorption spectrograms a t room temperature in a 10-cm. gas cell a t 25 mm. pressure for I, I1 and 111, and liquid film for IS'. ._____

Compound

CF3CCl=CCI(OCHs) CFaCCl~CCI(OCzH,) CFaCCl=CCI(OCsH,) CFaCCkCCl(OC4He)

Mol,

wt ,

192.97 207.00 221.02 235.00

Mass suscept. x 108

Molar suscept. (cxptl.) X 106

-0.4726 - 91.10 - ,5072 - 105,0 - ,5294 -117.0 - ,5472 - 128.6

(1) Abstracted from the M.S. thesis of E. Halpern, University of Colorado, August, 1951. ( 2 ) J. D. Park, M. L. Sharrah, W. H . Breen and J. R.Lacher, T H I ~ ( 5 ) A. L. Henne, €1, Sf,Whaley and J. R. Stevenson, i b i d . , 6 8 , JOURNAL, 73, 1329 (1951). 3478 (1941). (3) J. D. Park, M . I,. Shmrrah Mud J. K. Lacher, i b i d . , 71, 2337 ( 6 ) f. R. Lacher, H , ~4~ Srrvby and J . n,park. ibld , 'la, 383 (1980)i (1M9). T I , 1797 (1949). (1) J. a.Park, C. M.Snow and I.R. I,acher, ibid., 78, 2842 (1951)

RE-ESTERIFICATION DURING

Aug. 20, 1952

THE

About 200 ml. of a 10% KOH solution of methanol was added to a 500-ml. round-bottom three-necked flask equipped with stirrer, dropping funnel and reflux condenser. was Then 36 g. of 1,1,2-trichloro-3,3,3-trifluoro-l-propene added slowly. After the heat of reaction had subsided, the reaction mixture was refluxed for about three to four hours, and allowed to cool. I t was then washed with water, the organic layer separated and dried over calcium chloride. Distillation yielded 17.4 g. of CF3CCI=CCl(OCHs) which

[COSTRIBUTION FROM

THE

HYDROLYSIS O F CELLULOSE ACETATE

4105

boiled at 107-108° (630 mm,). Under these conditions no CFaCC1HCC12(OCHI) was isolated. Similar methods were used for the ethyl, propyl and butyl derivatives. The yields were about 50% of theory. Infrared Spe&a.-The infrared absorption spectra were measured using an automatic recording Perkin-Elmer infrared spectrometer, model 1 2 ~ . BOULDER, COLORADO

CELLULOSE ACETATEDEVELOPMENT DIVISION,EASTMAN KODAKCOMPANY ]

Re-esterification during the Hydrolysis of Cellulose Acetate BY CARLJ. MALM,LEOJ. TANGHE, BARBARA C. LAIRDAND GLENND. SMITH RECEIVED MARCH15, 1952 Acetone-soluble cellulose acetate, when treated with 99.8y0 acetic acid containing a catalyst, esterifies, yielding products low in primary hydroxyl. In the presence of more than 2y0 water hydrolysis takes place, and the products contain increasing percentages of primary hydroxyl as the percentage of water is increased. Upon hydrolysis in other solvents where re-esterification is impossible, the products contain a high percentage of primary hydroxyl regardless of the amount of water present. In 95% butyric acid, considerable butyryl is introduced into cellulose acetate upon prolonged hydrolysis. Similarly, in 95% acetic acid, considerable acetyl is introduced into cellulose butyrate. A correlation was found between the optical rotation of the products and the percentage of primary hydroxyl present.

acid has recently been reported.' Among the several variables investigated, it was found that only the percentage of water in the hydrolysis bath afTABLE I fected the percentage of primary hydroxyl in the BEHAVIOR OF CELLULOSE ACETATE IN AQUEOUSACETIC ACID product. A high percentage of water gave a high Hydroxyl percentage of primary hydroxyl in the resulting Water, Time, Acetyl, per g . u. Sample % Catalyst hours % Total Primary [ o ] S ~ D " cellulose acetate. A (Original) 39.3 0.60 0.28 -14.6 In the continuation of this work, the behavior of A-1-1 0 . 2 0.01 .If 72 3 9 . 9 0.54 .22 -12.5 a cellulose acetate of 39.3% acetyl content has been A-1-2 HCl 168 40.7 .45 .15 -10.8 studied in acetic acid solution over a wider range of A-1-3 336 41.3 .39 .10 - 9 . 3 water content (Fig. 1). In the presence of only A-1-4 672 41.5 .37 .09 - 7 . 4 0.2% water (Table I, samples A-1-1 to 4-1-4) and a trace of hydrochloric acid catalyst, slight esterifi72 40.0 0 . 5 3 0.20 -11.0 A-2-1 1 . 0 0 01 M A-2-2 HC1 168 40.0 .53 .16 - 9 . 3 cation took place a t room temperature. The prodA-2-3 336 39.7 .56 .I3 - 6 . 0 ucts had reduced percentages of primary hydroxyl A-2-4 672 39.9 .54 .12 - 1 . 7 because of preferential reacetylation. It has long been known that boiling acetic acid can partially A-3-1 2 . 0 0 . 0 1 -11 48 39.8 0 . 5 5 0.24 -12.9 Variation in amount of primary hydroxyl in cellulose acetate during hydrolysis in aqueous acetic

A-3-2 A-3-3 A-3-4 A-3-5 A-4-1 A-4-2 A-4-3 A-4-4 A-4-5 A-4-6 A-4-7 A-5-1 A-5-2 A-5-3 A-5-4

A-5-5

HCl

5.0 0 . 0 5 J f HCl

20

0.10 Af HCl

120 384 624 960 48 72 120 168 240 288 336 24 48 72 96 120 144

39.9 .54 .20 39.7 .56 .16 39.6 .57 .16 39.0 .63 .16 3 9 . 3 0.60 0.24 38.7 .65 .23 37.4 .78 .24 36.2 .89 .25 35.0 1.00 .28 33.4 1.13 32.9 1.19 .32 38.3 0.69 0.34 37.2 .80 .39 36.4 .87 .42 35.8 .92 .44 34.3 1.06 .49 3 3 . 5 1.12 .53 lb 39.0 0.63 0.31 3 37.5 .77 .39 5 36.1 .90 .45 6 35.3 .97 .49 7 34.8 1.02 .51 8 33.2 1 . 1 5 .58 tubes in ch1oroform:ethanoI

-10.3 - 6.0 - 4.0 - 1.7 - 9.4 - 4.6 - 1.1 2.7 4- 7 . 4 9.7 +11.2 -13.4 -11.2 - 9.3 7.6 - 5.4 3.7 -14.6 -12.6 -11.6 -10.6 -10.2 9.4 (85: 15

+ + -

A-5-6 A-6-1 45 h'one A-6-2 50 A-6-3 A-6-4 A-6-5 A-6-6 Measured in Zdm. by weight), at a concentration of 6 g. per 100 ml. selution. Thio suier was run at ateam-bath temperature,

-

I

I

I

02

04

I

I

I

06 08 IO Hydroxyls per glucose u m t

I I2

I

Fig. 1.-Behavior of cellulose acetate in aqueous acetic acid, effect of water concentration on primary hydroxyl. (1) C. J. Mala, L. J. Tanghe and

P B (iwe). ~

E. C. Laird, Tarn J o u n r ~TI, ~,