[CONTRIBUTION FROM THE CHEMICAL
LABORATORY O F HARVARD UNIVERSITY]
ON 1 , 2 AND 1 , 4 ADD1TION.l IV. NITROGEN TETROXIDE AND ISOBUTYLENE ARTHUR MICHAEL
AND
G. H. CARLSON
Received July 5, 1939
Ssidorenko2 found that nitrogen tetroxide acted upon isobutylene in ether solution to yield a small amount of the so-called bis-(isobutylene nitrosate), [(CH3)2C(ONO2)C(NO)H2]2(1)and, as the main product, a blue liquid, which gave a low yield of isobutylenediamine on reduction. Ipatieff3 showed that the dimeric product (I) and potassium cyanide yielded potassium nitrate and 0-cyanoisobutyraldoxime.* These products, analogous to those previously obtained by Wallach4from the corresponding isopentane derivative, established the structure of nitric ester I. We have confirmed this structure : sodium nitrate and a-nitroso-0-phenylsulfidoisobutane [ (CH&,C (SC~HE,)CH,(NO) J are formed quantitatively on treating the nitric ester with sodium thiophenolate, and catalytic reduction yielded ammonia and P-hydroxyisobutylamine. But the composition of the blue oil is uncertain. Ssidorenko2 obtained only a small yield of isobutylenediamine in the reduction, and Strack and Fanselow6could not experimentally confirm the result. This difference in experimental results led us to re-investigate the reaction and we have also endeavored to determine the chemical character of the main, complex, oily reaction product. Pure nitrogen tetroxide (prepared from lead nitrate), distilled into a cold ether solution of isobutylene, yielded a bluish-green solution, from which nitric ester I did not separate. I n petroleum ether the nitric ester appeared in variable yields (0 to 13.7 per cent.) and, although the 1 Previous papers: (a) MICHAEL AND WEINER,J . Am. Chem. Soc., 69, 744 (1937); ( b ) MICHAEL AND CARLSON, ibid., 69,843 (1937); ( c ) MICHAEL AND CARLSON, J. ORG. CHEM.,4, 169 (1939). The mechanism of the tetroxide addition has been discussed in lb. 2 SSIDORENKO, Zentr., 1907, I, 399. 3 IPATIEFF,ibid., 1901, 11, 1201. * The compounds named in this paper belong to the butyl series and are termed in accordance. These names are simpler and easier to connect with chemical structure than those founded upon the Geneva nomenclature, which unnecessarily complicates the chemical terminology of butyl and amyl derivatives. (A. M.) 4 WALLACH, Ann., 241, 296 (1888). 5 STRACX AND FANSELOW, J . physiol. Chem., 180, 153 (1928).
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2
ARTHUR MICHAEL AND G. H. CARLBON
experimental conditions were reproduced as far as possible, consistent results could not be obtained. The results of typical experiments are given in Table I (see under Experimental). The nitric ester separated from the crude reaction product in experiment 7 in a yield of only 0.1 per cent., but, after the volatile portion of the product had been distilled at low pressure, the residual non-volatile oil deposited 6.2 per cent. of the ester. From the crude products in experiments 8 and 9, the dimeric nitric ester separated in yields of 6 and 7 per cent., respectively, but the filtrates deposited more of the ester on longer standing (total yields are given in Table I). These results show that the nitroso-nitric ester derivative of isobutane, in contrast to the corresponding derivative of isopentane,lb is slowly and incompletely deposited from the crude reaction product. However, under similar conditions, the oily product formed in ether solution did not deposit the nitric ester, even after removal, at low pressure, of the easily volatile blue oil. Under no conditions could appreciable amounts of the ester be isolated from the products formed in ether solution (experiments 1-6). Accordingly, the nitroso-nitric ester of isobutane, as of isopentane, appears in higher yields in petroleum ether than in ether solution; the maximum yield of the isopentane derivative was 28 per cent.,'* while the highest yield of the isobutane product was 13.7 per cent. From the pasty reaction products formed in the absence of solvents (experiments 10-13), the bis-(nitric ester) was isolated in yields (7-12 per cent.) approximately the same as those obtained in petroleum ether (6-12 per cent.). While the yields of nitric ester I under comparable conditions (experiments 12 and 13) differed by 2 per cent., a change in temperature of 68" altered the yields only 4.6 per cent., (experiments 10 and 13), which shows that the course of reaction varies only slightly with moderate changes in temperature. Nitrogen tetroxide, volatilized slowly at room temperature into a current of gaseous isobutylene, reacted with evolution of heat; the addition was accompanied by oxidation, as was shown by the presence of carbon dioxide in the effluent gas. No solid separated from the green oil obtained with the tetroxide a t ordinary temperature in experiment 14. The nature of this green liquid could not be determined; reduction with zinc and acetic acid gave an inappreciable yield of basic product, which apparently consisted largely of hydroxylamine. At first, crystals mere formed on the walls of the reaction tube, when the tetroxide was passed slowly through a tube heated to 210' and then into a current of isobutylene diluted with nitrogen, but a green oil also appeared, which soon dissolved the crystals initially deposited on the glass surface. From the green solution only a very small amount of nitric ester I could be isolated and, because considerable oxidation had occurred, the oily product was not examined.
Petrol. . . . . . . . 60 60 60 Time, mins. . . . . 50 90 60 601 60 45 120 135 40 60 90 75240 Temp., "C . . . . . . -10 -8 -12 -51 -91 -88 -7 -5 - 5 - 8 0 - 1 0 -8 -12 40 Product, g. Bis-nitrate (I) 21 2 . 3 2 . 4 1 . 2 3 . 6 3 . 9 Liquid (A) . . . . 14.0 34i31.126 128 0 2 7 . 2 3226.826.0;22.824.9 128.8, 24.6 Calc'd Yield . . . . 14.5,32.534.0i25:9/25:6!25.032.2i33.532.732.525.635.7'32.41 21.6 Dist. gave, g. 9.8 11.7 15.0 11.4 3 . 5 Blue dist. (B) . Residue (C). . 22.8 12.9 11.0 13.8 6 . 2 1 0 . 5 1 2 . 2 7 . 4 8.61 10 12 % ' Bis-nitrate.. .
1
~
a Zinc dust (12 9.) was added to 5 g. of A in 50 cc. of glacial acetic acid, excess acid was distilled in vacuo, the residue was made basic and then steam-distilled: t h e distillate required 15 cc. of N hydrochloric acid for neutralization, and, accordingly, contained, at maximum, 0.7 g. of isobutylenediamine. A similar reduction was made with zinc and hydrochloric acid and the steam-distillate required 6 cc. of N hydrochloric acid for neutralization; the neutral solution, evaporated to dryness in vacuo, gave 0.1 g. of unidentified solid. * Oil 13 deposited no solid during 3 days a t room temperature; 2 g. of B, added to a solution prepared from 0.5 g. of sodium, 20 cc. of methyl alcohol and 3 g. of thiophenol, gave no inorganic salt and, as the only identified organic product, l g. of diphenyl disulfide. A portion of B (5.1 g.) was solidified a t -80"; the centrifuged mixture yielded 3.4 g. of blue solid, which, crystallized from an ether-petrol solution at -80°, gave 2 g. of white solid. Washed with ether at room temperature, the solid turned blue and fused to a wax, which, pressed on tile, gave 0.05 g. of the bis-nitroso-nitro derivative of ieobutane, m.p. 80-82". c A soliution of 5 g. of C in 50 cc. of ether was extracted a t 0' with a solution of 7 g. of sodium hydroxide in 75 cc. of water, and the aqueous solution was shaken with small portions of benzoyl chloride until acidic: the product (0.7 g.) was gummy and could not be identified. Five grams of C and 7 g. of potassium cyanide in 50 cc. of methyl alcohol gave, during 24 hours, 4.6 g. of insoluble salts: solvent was distilled in vacuo from the filtrate, t8heresidue was acidified and gave 2 g. of oily product which decomposed a t room 1;emperature. dOi1 C (mol. wt. calc'd for C4HsNnOl, 148; found 188.7) decomposed when distilled a t low pressure (bath temperature, 50'). Oil c' decomposed a t low pressure (bath-temperature, 50"): 8.5 g. of crude C, treated with 12 g. of dimethylaniline, gave 4.5 g. of oily product (b.p. 155-165'), which could not be identified. Two grams of B, added to a solution prepared from 0.6 g. of sodium, 20 cc. of methyl alcohol and 3 g. of thiophenol, gave no inorganic salt and the organic product (1.1 g.) gave 0.6 g. of diphenyl disulfide as the only identifiable product. Oil A deposited 0.05 g. of impure nitric ester I, m.p. 102". At low pressure, the filtrate evolved gas rapidly for 4 hours; when evolution of gas ceased, distillation 3 8
4
ARTHVR MICHAEL AND G. H. CARLSON
gave: (1) 3.5 g. of blue distillate and (2) a green residual oil, which deposited 2 g. of nitric ester I (m.p. 110-111"; mol. wt. calc'd for CaHsN204,296; found 292). The filtrate (16.6 g. of green oil) could not be distilled at low pressure: 3 g. of the oil, added to a solution prepared from 1 g. of sodium, 25 cc. of methyl alcohol and 7 g. of thiophenol, gave 0.8 g. of inorganic salt (found Na, 29.7; mixture contained 42% of NaNOs and 58% of NaN02) and 2.6 g. of oil, from which 0.9 g. of diphenyl disulfide was isolated as the only identifiable product. h Oil A deposited 1.5 g. of nitric ester I: the filtrate (21.8 g.) decomposed during low-pressure distillation. Oil A deposited 1.7 g. of nitric ester I: the filtrate (21 g.) was steam-distilled and gave: ( 1 ) 5.8 g. of blue and (2) 1.1 g. of green distillate; leaving 5.4 g. of viscous oil, which was not examined. Oil 1, added t o a solution prepared from 1.8 g. of sodium, 30 cc. of methyl alcohol and 8.7 g. of thiophenol, gave 0.8 g. of inorganic salt (found Na, 30.57; 30.51%; mixture contained 55% of P?ahiOs and 45% of ;h;aN02)and 4.4 g. of oil, which yielded 3.7 g. of distillate (a), b.p. 145-170" at 5 mm., leaving 0.3 g. of residue. Chromic anhydride (1.5 9.) was added slowly to a solution of 1 g. of S in 15 cc. of hot glacial acetic acid; the solution was poured into ice-water and yielded 0.5 g. of product, m.p. 85-89', from which 0.05 g. of diphenyl disulfone, m.p. 193-194', and 0.2 g. of p-phenylsulfonyl-a-nitroisobutane,m.p. 89-90", were isolated. A solution of 2.7 g. of 3 in 20 cc. of glacial acetic acid was treated with 15 g. of 30% hydrogen peroxide in 25 cc. of acetic anhydride and, until the vigorous reaction subsided, the mixture was maintained a t 35-40". The mixture, kept a t room temperature overnight, and poured into ice-water, gave 0.7 g. of p-phenylsulfonyla-nitroisobutane; m.p. 89-90" (Anal. Calc'd for CloHlaNOrS: C, 49.45; H, 5.35; N, 5.76; S,13.15. Found C, 49.43; H, 5.44; N, 5.72; S,13.60). i The pasty reaction product was diluted with ether: the solid was removed by filtration, but began to decompose and was immediately suspended in ether at -80" and again filtered. The bis-(nitric ester) (I), centrifuged from a methyl alcohol suspension, melted a t 117-118". Solvent was distilled i n vacuo from the ether filtrates; the residual oils, 12.8 g. and 10 g., respectively, decomposed violently within 3 minutes after isolation. k Oil A, during 60 hours, deposited only a trace of solid. A solution of 20 g. of A in 50 cc. of glacial acetic acid, containing platinum oxide catalyst, absorbed 170 cc. of hydrogen during 6 hours. Catalyst was filtered off, the filtrate added t o water; the oily product (1.3.7 g.) deposited 1 g. of nitric ester I. 2 The reaction mixture was stored a t 0" for 10 hours and the bis-nitric ester (I) filtered off: the filtrate (23.1 g. of green oil) decomposed rapidly. m The reaction mixture was stored a t 0" for 36 hours, ether was added, nitric ester I was removed by filtration; the solvent, distilled from the filtrate, left 28.8 g. of green oil. At low prt'ssure, the oil (27 9.) gave: (1) 3.8 g. of blue distillate and and (8) 22.7 g. of green residual oil, which solidified to a glass a t -80". A solution of 17.7 g. of d in 50 cc. of glacial acetic acid containing platinum oxide catalyst absorbed only 10 cc. of hydrogen during 12 hours. The excess isobutylene contained carbon dioxide, and water appeared in oil A. An ether solution of A waH washed with water, dried and the solvent distilled, gave 15.7 g. of green oil (1). One gram of dimethylaniline and 0.5 g. of 1 gave only an oily product. Five grams of 1, reduced with 5 g. of zinc in 25 cc. of acetic acid, gave 0.2 g. of product as the hydrochloride, which gave a positive test for hydroxylamine by the Bamberger method. A solution of 3.7 g. of 1 in 3 vols. of ether, treated with 5 g. of anhydrous potassium carbonate and 5 g. of benzoyl chloride, gave 5 g. of red oil, which, as i t decomposed on distillation, could not be identified.
ON
1,2
AND
1,4
ADDITION
5
The oil, which was separated from the pasty product in experiment 10, decomposed rapidly while still below room temperature. In experiment 12, too, the green oily product, although formed a t -8", decomposed violently after nitric ester I had been removed by filtration. Yet, the product formed under similar conditions in experiment 13 was stable and could be distilled at low pressure. It yieded an easily volatile blue, and a much less volatile green, viscous 0.11,which, like the crude product of experiment 11, could not be reduced catalytically. Decomposition of the green liquid formed in petroleum ether solution in experiment 7 was brisk at room temperature; the liquid, contained in an all-glass distilling apparatus, evolved gas so rapidly for four hours that a pressure below 5 mm. could not be maintained. When the evolution of gas had ceased, distillation a t low pressure separated the residue into a volatile blue, and a non-volatile green, oil, which, after separation of nitric ester I, was treated with sodium thiophenolate. The products, a mixture of sodium nitrate and nitrile and diphenyl disulfide, gave no insight into the composition of the oily addition product. During steamdistillai,ion, about one-half of the oil from experiment 9 decomposed with evolution of brown fumes; the volatilized green, mobile oil yielded with sodium thiophenolate a mixture of sodium nitrate and nitrite and an organic product, which, on oxidation, gave @-phenylsulfonyl-a-nitroisobutane. The sulfone was undoubtedly formed from the corresponding thio-ether, which, although the souxe is not definitely established,? probably was formed from a ,@-dinitroisobutane; accordingly, the latter compound constituted at least 3 per pent of the crude addition product. Although the liquid product formed in petroleum ether solution, or without solvent, decomposed easily, the product obtained in ether solution, could be distilled a t low pressure, and yielded a volatile, blue, and a non-volatile, green oil. With sodium thiophenolate, the blue distillate (experiment 2) gave diphenyl disulfide as the only identifiable product, which gave no insight into the composition of the blue oil. However, this oil solidified a t -80" to a blue mass, from which the adhering oil was centrifuged. The solid was crystallized from an ether-petroleum ether solution at -80" and gave a white solid, which, when washed with a few drops of ether at room temperature, changed to a waxy substance. From this wax a small amount of tlie poorly named, bis-(isobutylene (111), was isolated. The pseudonitrosite), ie., [(CH,)~C(KO~)CI:SO)H~]~ appearance of this product indicated that some nitrogen tetroxide had been reduced to the trioxide before the addition. Catalytic reduction of the distilled blue oil in experiment 4 (Table 11)
t The thio-ether may be derived from tlie nitro-nitrous or the nitroso-nitrous ester derivative of isobutane. The mechanism of the formation of the sulfide is not known, see IC, footnote 11.
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ARTHUR MICHAEL AND 0 . H. CARLSON
TABLE I1 CATALYTIC REDUCTION OF ADDITIONPRODUCTS Hz AEBORBED
PRODUCT REDUCED
- --
Oil
From apt.
-
g.
,.
- -_
Time, hrs.
__
PRODUCTS
NHIC1, g. -
3"
31.1
14.1 24.1
5.1
4b
11.7
7.06 56
1.4
5c
15
10.2 71
1.8
Fractions, g.
'1 2
