[CONTRIBUTION FROM THE CHEMISTRY
LABORATORY O F NORTHWESTERN
UNIVERSITY ]
CHLOROACETONE CYANOHYDRIN AND RELATED COMPOUNDS CHARLES D. HURD
AND
CHARLES H . RECTOR, JR.’
Received May 18, 1946
For the present study of chloroacetone cyanohydrin UltBe’s synthesis (1), which involves the addition of an excess of dry hydrogen cyanide to chloroacetone in the presence of a trace of saturated potassium cyanide or potassium carbonate solution, was found to be themost satisfactory out of several tried. This method has also been used successfullyby Justoni (2) for the preparation of ‘the cyanohydrin of chlorinated methyl ethyl ketone. The conversion of chloroacetone cyanohydrin into j3-chloro-a-hydroxyisobutyric acid by the hydrolytic action of conc’d hydrochloric acid was reported by Biechoff (3). We found this to be a satisfactory method of synthesis for this acid. Both ketene and acetic anhydride were effective in the acetylation of the cyanohydrin if a trace of sulfuric acid was present as catalyst. As would be predicted, the acetate boiled at nearly the same temperature as the cyanohydrin. Alcoholysis of chloroacetone cyanohydrin (I) into methyl P-chloro-a-hydroxyisobutyrate (11) was carried out by use of methanol and conc’d sulfuric acid. Formed in this reaction also was a substantial quantity of unidentified crystalline
C lCHz
\ / C / \
CH3
OH
ClCHz
CN
CHs
I
\ / C / \
OH
COOCH3
I1
by-product. It is a nitrogen-containing, high niolecular weight (352) substance, which changes to P-chloro-a-hydroxyisobutyricacid on acid hydrolysis. There appeared to be little or no tendency for the cyanohydrin to undergo dehydration in this reaction. This is in contrast to the behavior of acetone cyanohydrin which yields a substantial amount of methyl methacrylate under similar treatment. As will be seen from the evidence to follow, a substantial stability was imparted to structures I and I1 by the presence of the chlorine atom. Boiling thionyl chloride (4) converts acetone cyanohydrin into a mixture of methylacrylonitrile and a-chloroisobutyronitrile, yet SO-SO% of I or I1 are recoverable after such treatment. A high recovery of I or I1 also follows treatment of either compound in hot benzene solution with phosphorus pentoxide, yet this method is recommended (5) for the conversion of an a-hydroxyisobutyric ester into a methacrylic ester. Phosphorus oxychloride is another reagent which dehydrates methyl a-hydroxyisobutyrate (6), but three-fourths of I1 was recoverable after treatment of it with phosphorus oxychloride. It T T ~ Snot possible to dehydrate I catalytically over alumina at 350” because 1
duPont Felloa- in Chemistry, 1940-1942. 441
442
C. D. HURD
.4ND C. H. RECTOR, JR.
pyrolosis into hydrogen cyanide and chloroacetone occurred instead, even at low pressures. This is the decomposition which occurs during ordinary distillation (3). Dehydration of (I) was successfully accomplished by the action of a mixture of thionyl chloride and pyridine. Thionyl chloride could not be used alone, and quinoline was not a satisfactory substitute for pyridine. This dehydration caused the production not only of /3-chloro-a-methylacrylonitrile,ClCH= C (CH3)CN (111),but also a ,p-dichloroisobutyronitrile, C1CH&C1(CH3)CN. The former was greatly in excess. This type of reaction has been used in the dehydration of other cyanohydrins (7). Structure 111, rather than a-(chloromethyl)acrylonitrile, C1CH2C=CH2, was assigned for several reasons. Strong
I
CN evidence was the inertness of the compound towards alcoholic silver nitrate or sodium phenoxide. Ozonolysis to acetic acid with no concurrent formation of chloroacetic acid or formaldehyde was confirmatory evidence. Lack of any tendency to polymerize was also in keeping with structure 111. It is interesting to note that sodium p-chloro-a-methylacrylate, produced from the nitrile by hydrolysis and neutralization, did not pyrolyze into methylacetylene on refluxing the solution. Many p-chloro salts do break down (8) with such treatment. This suggests that this salt (IV) and the nitrile I11 may be of the trans configuration Cl-C-H
C1-C-H
II
0ONa
CH3-C-C
II
CH,-C-CN
I11
IV
because the analogous potassium 6-bromotiglate (V) also is stable (9) in hot water. In contrast, potassium /3-bromoangelate (VI) breaks down with ease on boiling with water into dimethylacetylene. Br-C-CH3
II
CH3-C-COOII V
CH2-C-Br
II
CH3-C-COOK VI
Reactions of methyl p-chloro-a-hydroxyisobutyrate(11) were investigated, many of which paralleled those listed above for (I). Acetylation of the hydroxyl group was accomplished by means of ketene. This acetate (VII) underwent pyrolysis at 500" (65 seconds) to produce methyl /3-chloro-a-methylacrylate (VIII) : ClCH:,
OCOCH,
\ / C / \
CH3
COOCH, VI1
ClCH=C-COOCHz
I
CH3 VI11
CHLOROACETOXE CYANOHYDRIN
443
Some hydrogen chloride was detached concurrently. No decomposition occurred a t 390", and three-fourths of the compound was recovered a t 450". When alumina was used as catalyst with I1 at 250" or 350". gaseous products were formed, but there seemed to be no production of VIII. Just as I was dehydrated to 111 by the mixture of thionyl chloride and pyridine, so also I1 was found to dehydrate into VIII. Some chlorination of the hydroxyl group of I1 occurred simultaneously to produce methyl a ,p-dichloroisobutyrate. On the other hand, substantial recovery of 11, without formation of VIII, occurred when these reagents were used: thionyl chloride alone, phosphorus oxychloride, or phosphorus pentoxide suspended in benzene. Some tarry products were produced, however, in these operations. EXPERIMENTAL PART
Chloroacetone cyanohydrin. A supply of chloroacetone was generously furnished for this investigation by Commercial Solvents Corporation. It contained water for purposes of stabilization (10). T o this wet chloroacetone was added some solid sodium carbonate. The mixture was shaken well, then the liquid was decanted and distilled. The purpose of the sodium carbonate is t o neutralize the acidity which is present. It is not added as a desiccant, because anhydrous chloroacetone may be made simply by distillation. It was our experience, however, that poor yields of the cyanohydrin were frequently encountered if the chloroacetone was distilled without the treatment nrith sodium carbonate. Anhydrous chloroacetone (46.4 g.), b.p. 119-120°, and anhydrous hydrogen cyanide (23 ml.) were cooled in an ice-bath under a reflux condenser. A vigorous reaction started when five drops of saturated potassium cyanide solution was added as catalyst. The previous treatment with sodium carbonate eliminated any acid which would have destroyed this catalyst. After thirty minutes five drops of conc'd sulfuric acid was added. Vacuum distillation of the product yielded 53-56 g. (87-9oQ/o) of chloroacetone cyanohydrin: b.p. 108-110" (20 mm.), n: 1.4520. The substance is soluble in water. Kone of the cyanohydrin was obtained by interaction of saturated sodium cyanide solution with a cooled suspension of chloroacetone sodium bisulfite, although Gaind (11) reports a 38.5% yield by this method. Reactions of Chloroacetone Cyanohydrin Hydrolysis. 8-Chloro-a-hydroxyisobutyricacid was formed in 62% yield following Bischoff's directions (3). Conc'd hydrochloric acid (40 ml.) was employed with 17 g. of ( I ) , the mixture being left a t room temperature for two days, and then two hours at 100". Before ether extraction of the acid the mixture was diluted with 10 ml. of water. After crystallization from benzene the acid melted at 109-110". Alcoholysis. Fifty ml. of conc'd sulfuric acid was added t o 52.3 g. of chloroacetone cyanohydrin in 150 ml. of methanol. The solution was refluxed on the steam-bath for sixteen hours, then cooled and poured onto 100 g. of cracked ice using 40 ml. of rinse water, and finally extracted with ether. The ether solution was dried over anhydrous sodium sulfate. The ether was distilled and the remaining oil was distilled t o give a 5470 yield of mcithyl 6-chloro-a-hydroxyisobutyrate, b.p. 18&190", n: 1.4440, d f : 1.2295. A n a l . Calc'd for C5H&10a: C1, 23.24; Mol. wt., 152.5. Found: C1, 23.71, 23.52; Mol. wt. (cryoscopically in benzene), 156.2, 157.2. A 4ooj, yield of this methyl ester was obtained with a 10-hour refluxing period (80 ml. of conc'd sulfuric acid, 177 g. of (I),100 ml. of methanol; yield, 57 6.) but a substantial quantity of dark solid material remained undistilled after removal of the ester by vacuum distillation. Crystallization from water with Norit treatment yielded 10.3 g . of white needles which melted at 126.5-127.4'. This material liberated ammonia on boiling with alkali,
444
C . D. HURD AND C. H. RECTOR, J R .
and acid hydrolysis converted it t o p-chloro-a-hydroxyisobutyricacid. It has been analyzed, but not identified as yet. Anal. Found: C1 (Na-NHS method) 36.14, 36.28; (Parr fusion method) 36.16. Mol. wt., cryoscopically in benzene, 352. Acetylation. Into 52 g. (0.43 mole) of chloroscetone cyanohydrin containing 2 drops of conc'd sulfuric acid was passed 0.43 mole of ketene gas. Since heat was evolved the flask was placed in cold water. The product was washed with both dilute potassium carbonate and hydrochloric acid solutions, and finally with water. Twenty ml. of ether was added and the solution was dried over sodium sulfate. Distillation yielded 49 g. (70%) of p-chlorom-acetoxyisobutyronitrile : b.p. 107-108" (17 mni.) . To 0.1 mole (12 9.) of chloroacetone cyanohydrin was added 10 ml. of acetic anhydride and 3 drops of conc'd sulfuric acid. The solution warmed and turned yellow. During two hours of refluxing hydrogen chloride fumes were given off. The mixture was poured into 50 ml. of water and extracted with ether. The extract was dried and distilled; yield, 8.1 g., b.p. 111-112' (20 mm.). Analysis of this material was high in chlorine, pointing t o the presence of some unacetylated cyanohydrin. The above experiment was repeated by W. A. Yarnall with these quantities of reagents: the cyanohydrin, 39.9 g.; acetic anhydride, 34.0 g.; sulfuric acid, 1 drop. The reaction mixture was cooled by an ice-bath for thirty minutes, then left a t 25' for several hours. Distillation a t 15 mm. yielded 34 g. (75%) a t 109-11lo; d i 5 1.191. Twenty ml. of this was extracted with two 50-ml. portions of water (about 1.5 ml. dissolved) after which i t was dried over sodium sulfate and redistilled; b.p. 105-105.5" a t 12 mm.; n; 1.4390. Anal. (by M. Ledyard) Calc'd for CBHsClKOz: N , 8.66. Found: N , 9.09. Conversion to B-chloro-a-methyzacrylonitTiZe. One mole (120 6.) of chloroacetone cyanohydrin was placed in a 1-liter three-neck flask fitted with stirrer, reflux condenser, and dropping-funnel. When the chloroacetone cyanohydrin was thoroughly cooled in an icebath, 2 moles (162 ml.) of ice-cold anhydrous pyridine was added slowly to the flask. Through the dropping-funnel was added slowly 2 moles of thionyl chloride (146 ml.) with vigorous stirring. The mixture turned brown immediately and a brown solid formed which dissolved as more thionyl chloride was added. The mixture was stirred for twelve hours a t 0" and was then heated for three hours in a water-bath kept a t 80-85". One hundred ml. of water was added slowly to the cooled, stirred mixture. Sulfur dioxide was given off. More water and 10 ml. of concentrated hydrochloric acid were added. The dark solution was then extracted several times with ether. The ether solution was washed with dilute sodium hydroxide solution until free from acid. The ether solution was dried for six hours with anhydrous sodium sulfate but was still wet, so phosphorus pentoxide was added. The ether solution was filtered and distilled. The yield of clear liquid, b.p. 14C-17Oo, was 69.2 g. From a second run half this size was obtained 34.5 g. of liquid boiling a t 141-170". The above two fractions, 103.7 g., were combined and thrice fractionally distilled at atmospheric pressure through a 20-cm. Vigreux column to yield these fractions. (A) 17-20 g., b.p. 127-129", ng 1.4592. This fraction possessed a sweet odor and gave a negative test B7ith alcoholic silver nitrate solution. It was p-chloro-a-methylacrylonitrile. It displayed no tendency t o polymerize on standing. (B) 4C-50 g., b.p. 160-162', or 55-56' (16 mm.), ng 1.4568. It appeared to be a constant boiling mixture of 6-chloro-a-methylacrylonitrileand a, 6-dichloroisobutyronitrile. Anal. of A . Calc'd for C4H4ClK:C1, 34.94; Mol. wt. 101.5. Found: C1, 34.69, 34.75. Analysis was by the Parr method. The method using sodium in liquid ammonia gave high, erratic results, caused by the presence of the cyanidc radical. Anal. of B . Calc'd for C4H5C12N:C1, 51.39; Mol. wt., 138.0. Found: C1, 41.78, 41.20; Mol. wt., 114.5, 114.8. Behavior of fraction B . Tlyo-thirds of the substance was recovered following treatment with an equal aeight of dry pyridine a t 100" for ninety minutes. Half of the substance was recovered unchanged after 10.5 g. in 20 ml. of benzene was warmed for ninety minutes
CHLOROACETONE CYANOHYDRIN
445
with 3 g. of powdered potassium hydroxide. Only partial hydrolysis occurred (0.7 g. of product of b.p. 200-205" from 5 g. of original substance) after being in contact with hot (100") conc'd hydrochloric acid overnight, and over half of the starting substance was recovered. Data concerning the reaction of chloroacetone cyanohydrin with other compounds which were found to be incapable of dehydrating it into 0-chloro-or-methylacrylonitrile are collected in Table I. Action of alumina. Twenty ml. of 8-14 mesh activated alumina pellets, obtained through the courtesy of Dr. V. N . Ipatieff of this laboratory, was placed in a vertical Pyrex tube, 30 x 1.2 em. The catalyst chamber a t 350' and 30 mm. pressure was preceded by a preheater into which the chloroacetone cyanohydrin dropped. From 23 g. of the latter, introdnced during twenty minutes, an amber liquid was collected in an ice-trap from which 8 g. of chloroacetone, b.p. 118-119", was isolated.
Reactions of p-Chloro-or-methylacrylonitrile Formation of 6-chloro-or-methylacrylic acid. Two grams of the nitrile was added to 10 ml. of conc'd hydrochloric acid and the mixture was warmed on the steam-bath for one hour. On diluting and cooling, long white needles separated. These were recrystallized from hot water; yield, 0.7 g., m.p. 58.0-58.5'. One-half g. of this acid was dissolved in an excess of a sodium hydroxide solution. The solution was refluxed for an hour but no gases escaped through the condenser. The solution was then acidified and the original acid was recovered, m.p. 56.5-58". A n a l . Calc'd for C4H&101: Neut. equiv., 120.5. Found: Keut. equiv., 121.5, 122.1. Alcoholysis of p-chloro-or-methylacrylonitrile. To 9.8 g. (0.1 mole) of sulfuric acid in 1.0 mole of methanol was added 10.1 g. (0.1 mole) of (111). The solution was refluxed for three hours. The excess methanol was removed on the steam-bath. Fifty ml. of water was added and the resulting solution was ether extracted. The ether solution was dried over phosphorus pentoxide. Distillation yielded 4.4 g. of a liquid, b.p. 127-141' and n: 1.4580, and 1.3 g. of methyl p-chloro-a-methylacrylate which boiled a t 141-143'; n: 1.4562. Ozonolysis of p-chloro-or-methylacrylonitrile. Two g. of this nitrile was added t o 50 ml. of carbon tetrachloride. An ozone stream was passed into the cooled solution for fifty minutes. The solvent was then removed under vacuum. An oil remained which warmed but was cooled under running water. Ten ml. of water was added and the solution was allowed to stand for two hours before warming on the steam-bath. The escaping gases smelled of hydrogen cyanide and were passed into an alcoholic solution of dimethyldihydroresorcinol t o detect any formaldehyde. KO precipitate was obtained on adding water. Ten ml. of conc'd hydrochloric acid was added and the solution was warmed. One-half of the solution was treated with p-nitrobenzyl bromide. A solid separated on standing that melted a t 73-74', indicative of p-nitrobenzyl acetate which melts at 78". The other half of the solution was tested for a carbonyl-containing compound by neutralizing and adding sodium acetate and phenylhydrazine hydrochloride. No solid was obtained. I n a like manner, 1.7 g. of the nitrile was placed in 35 ml. of carbon tetrachloride and an ozone stream was passed in for forty minutes. The ozonide was decomposed by boiling with water. This sample was tested for chloroacetic acid by adding phenol to the basic solution. S o phenoxyacetic acid was obtained. Non-reaction with phenol. One g. of the starting 2 g. of p-chloro-or-methylacrylonitrile was recovered following eight hours of refluxing with 20 ml. of acetone, 2 g. of phenol, and 3 g. of anhydrous potassium carbonate. There was no replacement of chlorine by the phenoxy group. Reactions of Methyl p-Chloro-a-hydroxyisobutyrate Acetylation b y ketene. Ketene gas was passed into 11, containing a trace of conc'd sulfuric acid, until a small excess of ketene had been introduced. After washing and drying
446
C. D. HUED A S D C. H. RECTOR, JR.
the product it m-as distilled to give a 75y0 yield of methyl p-chloro-a-acetoxyisobutyrate, b.p. 212-213'. For analysis, this material was redistilled: b.p. 91-92" (13 mm.), n f : 1.4380. A n a l . Calc'd for C,HIIClO4: C1, 18.22. Found (Stepanow method) : C1, 18.90, 18.22. Pyrolysis of the acetate. Forty-nine grams out of an original 51.2 g. was recovered after passing through a Pyrex tube (1.5 x 20 cm.) maintained a t 390" and 10 mm., and 26.8 g. out of an original 38.7 g. when the methyl 0-chloro-a-acetoxyisobutyrate was passed through a larger tube (2.2 x 30 cm.) a t 450' and 750 mm. h little tar was formed in the latter run. Another pyrolysis was run with the furnace heated to 500". Twenty-six g. of methyl p-chloro-a-acetoxyisobutyratewas passed through the tube over a period of eighty minutes, TABLE I EFFECT O F SEVERAL DEHYDRATIXG AGENTS I OR 11, 0 .
BENZEm,
PEAGENT, G.
ML
.
1
REACTION PERIOD
hours
PRODUCTS
1
temp., "C.
Chloroacetone Cyanohydrin ~
48 112 112 21 21
SOClz, 96; quinoline, 103 SOCln, 119 SOC12,119 PC13, 48 (PCl,, 49; \pyridine, 50
0
'i
24 50.5
-
60
{
-
;I
80
2 2 1.7
tar
100 reflux reflux reflux
2 g. of ether-sol. product
reflux
1 g. of ether-sol. product
reflux 0', exother-
tar
+ 8 g.
chloroacetone
red t a r
Methyl p-Chloro-a-hydroxyisobutyrate ~
reflux reflux reflux
23 7 9.7
-
some HCI some t a r
or a contact time of 65 seconds. This time there was more carbon and less tar in the reaction tube. Hydrogen chloride fumes again were given off, Distillation yielded six fractions: B.P.,
"C.
96-111 112-131 131-133 41-50 51-84 85-94
PRESSUBE, MM.
WEIGHT, 0 .
750 750 750 10 10 10
1.7 5.8 0.6 3.0 2.7 4.9
:n
1.4108 1.4210 1.4536 1.4525 1.4508
The fourth fraction (b.p. 41-50' at 10 mm.) was chiefly methyl p-chloro-a-methylacrylate and the higher-boiling fractions were mixtures of this ester and the starting material. Dehydration of 11. Into an ice-cold mixture of 15.2 g. (0.1 mole) of I1 and 16 ml. (0.2 mole) of dry pyridine was slowly added 14.5 ml. (0.2 mole) of thionyl chloride. Vigorous stirring was maintained during this addition and for several hours thereafter. Then water and hydrochloric acid were added, the mixture ether extracted, the ether solution washed with dilute alkali solution, dried, and distilled. The product collected a t 160-190" weighed 8.8 g.
CHLOROACETONE CYANOHYDRIN
447
Another similar run, starting with 25 g. of the ester yielded 17.8 g. of b.p. 140-190'. The combined 26.6 g. was fractionated with these results (b.p. "C., wt. g.): 140-145, 3.9;145-165, 2.8;165-173, 5.7;173-175,9.2;residue, 2.4. The first 3.9-g.fraction, on redistillation, gave a sweet-odored fraction of b.p. 143", n: 1.4558, which was analyzed. It gave no precipitation of silver chloride when treated with an alcoholic silver nitrate solution. It was methyl 8-chloro-or-methylacrylate. No attempt was made t o characterize the higher-boiling fractions, but the substantial absence of I1 (b.p. 188-190') was revealed by the fact that the fractions were all of lower boiling point. Presumably, methyl a,& dichloroisobutyrate was present. Anal. (Na-NH3method) Calc'd for C6H,C102: C1, 26.4. Found: C1, 27.3,27.4. The action of alumina. Two out of five experiments will be mentioned, one at 250" and one at 350". Twenty ml. of 8-14 mesh activated alumina catalyst was placed in a Pyrex tube (30x 1.2cm.) which was heated electrically. I n the 250" experiment, 12.3g. of I1 was passed over the catalyst during ten minutes, and 10.8 g. was recovered. This 10.8 g. was used in the 350" experiment during ten minutes. I n this run, only 4.1 g. of dark-colored liquid, b.p. 45-65', was collected. There was an extensive production of gaseous products, including hydrogen chloride, but no methyl 8-chloro-a-methylacrylate. SUMMARY
These reactions of chloroacetone cyanohydrin are reported: hydrolysis with conc'd hydrochloric acid to 0-chloro-a-hydroxyisobutyricacid, alcoholysis to methyl p-chloro-a-hydroxyisobutyrate,acetylation by both acetic anhydride and ketene to p-chloro-a-acetoxyisobutyronitrile,dehydration to p-chloro-amethylacrylonitrile by thionyl chloride and pyridine, the decomposition of the cyanohydrin into chloroacetone either by distillation a t atmospheric pressure or in the presence of alumina a t 350" and 30 nun. pressure. The essential inertness of the cyanohydrin towards thionyl chloride (without pyridine) , phosphorus trichloride, or phosphorus pentoxide is pointed out. p-Chloro-a-methylacrylonitrile mas converted to 6-chloro-a-methylacrylic acid and its methyl ester by hydrolysis and alcoholysis. The nitrile was charaeterized by its inability to polymerize, its inert halogen, and by ozonolysis. These reactions were developed for methyl 0-chloro-a-hydroxyisobutyrate: acetylation by ketene to methyl p-chloro-a-acetoxyisobutyrateand pyrolysis of the latter to methyl /3-chloro-cu-methylacrylateldehydration t o methyl p-chloroa-methylacrylate by means of thionyl chloride and pyridine but not by these reagents : thionyl chloride alone, phosphorus oxychloride, phosphorus pentoxide, or activated alumina a t 250" or 350". EVANSTON, ILL. REFERENCES
(1) ULTEE,Ber., 39, 1856 (1906); Rec. trav. chim., 28, 17 (1909). (2) JUSTONI,Gazz. chim. ital., 69, 378 (1939). Ber., 6, 863 (1872). (3) BISCHOFF, (4) KAUTTER AND GRAEFE,U. S. Patent 2,210,320,Chem. Abstr., 36, 139 (1941);MACQ, Bull. classe. sci., Acad. roy. Belg., 12,753 (1926);Chem. Zentr. I, 880 (1927). (5) HENRY,Bull. Acad. r o y . Belg. (3)36, 22, 31 (1898);Chem. Zentr. 11,662 (1898);MACQ, ref. 4; SCORAH AND WILSON, Brit. Patent, 416,007,Chem. Abstr., 29, 814 (1935); WAINEAND WILSON,Brit. Patent, 466,504,Chem. Abstr., 31,7894 (1937); BRUSON, U. S. Patent 2,100,993,Chem. Abstr., 32, 953 (1938).
448
C. D. H U R D AND C. H. RECTOR, JR.
(6) CRAWFORD, Brit. Patent 410,208 (1934);Chem. Abstr., 28, 6157 (1934). (7) COOKAND LINSTEAD, J . Chem. Soc., 954 (1934); BACHMANN AND STRUVE, J . Am. Ckem. Soc., 63, 2589 (1941). ( 8 ) HURD,“The Pyrolysis of Carbon Compounds,” Reinhold Publishing Co., New York, 1929, pp. 489-490. AND HENZE, Ann., 313,243 (1900). (9) WISLICENUS (10) MOREY,U.S.Patent 2,243,484;Chem. Abstr., 36, 5511 (1941). (11) GAIND,J. Indian Chem. Soc., 14, 13 (1937).
