J. CRAIK,K. H, BERGER AND A. W. BROWNE
2380
[CONTRIBUTION FROM THE
BAKERLABORATORY OF
Azido-dithiocarbonic Acid. VIII.
CHEMIS7XY AT CORNELL
Vol. 56 UNIVERSITY]
Guanidine Trinitride and Azido-dithiocarbonaW
BY J. CRAIK,K. H. BERGERAND A. W. BROWNE Guanidine Trinitride, HNC (NH2)yHNs Preparation.-It was found possible to prepare guanidine trinitride by interaction of (1) guanidine hydrocbloride and silver trinitride, (2) guanidine sulfate and barium trinitride, and (3) guanidine carbonate and hydronitric acid. The third method, which yields 9OV0of the purified final product, was adjudged the best To 5 g. of guanidine carbonate dissolved in about 50 cc. of water 3 5% aqueous hydronitric acid was added until effervescence ceased. The solution was evaporated nearly to dryness over the steam-bath, and was Jlowed to cool, with the result that a crystalline mass of guanidine trinitride was obtained. This product was recrystallized from water, washed with small amounts of ice water and placed in a vacuum desiccator over phosphorus pentoxide. Anal. Total nitrogen was determined hy the method of Rumas, and the Qinitride graup by that af Rawbig. Calcd far HNC(NHsk.HN3: C, 11.70; H, 5.90; N (total), 8240; Na, 40.99. Found: C, 12.03, 11.64; H, 5 81, 5.97; N (total), 82 5, 82.45; Na, 41.25. Properties.-Guanidine trinitride crystallizes from aqueous 5olution in the form of Iwg, colorless prisms (m. p 93.5' that deliquesce slowly under ordinary atmospheric conditiws. At 20', 100 g, of water will dissolve 159.2 g. of the salt, which i s also somewhat soluble in the following liquids, listed in the order of decreasing solvent action: 80% ethanol, acetone, methanol, absolute ethanol and ether. It is not appreciably soluble in chloroform, benzene, carbon disulfide or carbon tetrachloride, Ayueoua solutions respond to the ferric chloride test2 for the trinitride ion, and yield hydrogen trinitride vapar wheti acidified. In aqueous solution a t 40' the trinitride ion discharges upon the carbon disulfide molecule, with formation of the azidodithiocaxbonate ion: NsC& --+ SCSNl-. This reaction takes plate in conformity with the general behaviw of inorganic trinitrides in aqueous solution toward carbon disulfide.3 The organic trinitrides do not condense directly with carbon disulfide to form the corresponding azido-dithiocarbonates.'"
+
Guanidine Azido-dlthioearbonate,
HNC (NH2)2*HSCSN3 Preparation.-Two methods were employed in the preparation of guanidine azido-dithiocarbonate. (1) For the earlier artieIes of this series see (a) Tsns JOURNAL, 46, 2804 (195a). (b) 47, 269% (19%5): (39% 917 (E387); (d) 4% 2129 (19.271, (e) 68, 1928, (f) 2806 (1930); (g) 06, 1116 (1934). The expenmental work recorded in the current articte was carrfed out by D r Cmik es P wt d w iofaratal "@inor" dwlaa the aeM of his incumbency as CQWPOWVWkh Fund Rellpw at Cqs%eU Uaiver4 t y , and Mr Berger as a part of his "Senior Research " Prossc, rbid., tr, IWW) (3) $ee, for exeIspk. Brwvne and HoeL % b a d , (a) 6% 2106, (b) 2315 ( 1 9 2 2 ) . ( c , Currier with Browne, ihzd , 44, 2849 ( 1 9 2 2 ) ; also
w
tar
R*
l(P)
*ad l(d)
(1) Freshly prepared solid azido-ditbiocarbonic acid,'" still moist, was added to an aqueous solution of guanidine carbonate until no further evolution of gas was observed to take place. The slightly turbid liquid was filtered, and the filtrate concentrated in vucuo over phosphorus pentoxide. The resulting sirupy supersaturated solution, when vigorously stirred with a glass rod, yielded slightly yellowish crystals to the amount of about 60% of the theoretical yield. By recrystallizing this product from water, pure colorless crystals were obtained. (2) To a solution prepared by dissolving 2 g. of guanidine trinitride in 25 cc. of water was added 2 cc. of carefqlly purified carbon disulfide. The reacting mixture was held a t 40" in a tightly-stoppered 100-cc. battle for sixty hours A t the end of this period portions of the solution failed to respond to the iodine testabfor unchanged trinitride ion. After filtration, concentration of the filtrate in v a w , and recrystallization of the solid product had been effected, the purified substance was stored in vacuo a t a temperature below 1 0'. Anal. Total nitrogen was determined by the method of Dumas, sulfur with the aid of the parr bomb, and the azido-dithiocarbonate radical according to the procedure of Volhard.Ib Calcd. for HNC(NH&.HSCSNs: C, 13.47; H, 3.40; N (total), 47.19; S, 35.94; SCSNa, 66.3. Found: C , 13.6, 13.6; H, 3.7, 3.6: N, 47.3, 47.5; S, 35.99, 35.90; SCSNs, 65.8. Properties.-Guanidine azido-dithiocarbonate crystallizes from aqueous solution in the form of colorless prisms. Like the other inorganic compounds'o~ldof the azido acid, and unlike the alkyl and acyl derivatives'" thus far studied, it is photosensitive. In the dark it may be stored at temperatures below 10' dla W G U I ) over phosphorus pentoxide for days without appreciahle decomposition. I t was found to dissolve readily in water and in acetone, less readily in 95% ethanol and not appreciably in ether. Heated on platinum foil it decomposes rapidly, with evolution of much gas, hut without detonation. I n the capillary tube it decomposes a t 88-90'. In aqueous solution the azido salt interacts with silver nitrate to form the insoluble silver azido-dithiocarbonate.lbIf Interaction of Guanidine Carbonate and Azido-carbondisulfide.-Equivalent amounts of guanidine carbonate (1.80 9.) in aqueous, and azido-carbondisulfide (2.36 9.) in acetane, solutiaa were brought together at rwrn temperature. The resulting satutiaa immediately assumed a greenish-yellow color, and a brisk evolution of gas took place. After five hours about 0.5 g. of free sulfur was recovered by filtration, and 1.75 g. of a crystalline solid identified as guanidine thiocyanate (m. p. 118') was obtained from the Mtrate,
The initial readion that occurred is analogous with that of an J k l i u p the halogenoid azidocarbondisuIfide,* and may be expressed by the equation ,4)
Browne. IIoel, Smith a s d Swezey, $bad., 46, W
l 6.1WS).
Nov., 1934
THE
+ +
METHYLENE RADJCAL
238 1
( H N C ( N H ~ ) ~ ) ~ . I I Z C(SCSNJ)~ O~ + HNC( NE1z)yHSCSNa HNC(NHZ)~.HOSCSN~CC+
conctusion that two atoms of nitrogen gas per mole of (SCSN&, or one-third of the total azide The very unstable oxy-azida-dithiocarbonate nitrogen, were liberated at once. This confirms quickly decomposes, with evolution of two-thirds the theory that the oxy-azido-dithiocarbnate of its azide nitrogen as gas (or one-third of the undergoes very rapid decomposition under the total nitrogen of the original azido-carbondisulfidcr prevailing conditions. used), deposition of sulfur and formation of the Summary oxy-thiocyanate. This would tend to form thir Guanidine trinitride, H?(C(NH&.HS3 (m. p. tri-oxy-thiocyanate, or chlorate ana10g.~ The guanidine azido-dithiocarbonate, on long 93.5'), has beefi prepared b y interaction, in aquestanding, decomposes quantitatively, yielding ous solution, of (1) guanidine hydrochloride and nitrogen, sulfur and the thiocyafiate. Five- silver trinitride, (2) guanidine sulfate and barium sixths of the total original azido-dithiocarborlate tfinitride, and ( 3 ) guafiidine carbonate and hydrois therefore converted into thiocyanate, while the nitric acid. Guanidine azido-dithiocarbonate, H S C ( S I-12)2. remaining sixth yields the chlorate analog, guanidine tri-oxy-thiocyanate, or cyanosulfate, HSCSNJ (dec. SS-OOO), has been prepared by which hydrolyzes illto the sulfate and cyafiide.5 interaction in aqueous solution of (1) guanidine The amount of frev sulfur recoveted in this carbonate and azido-dit hiocarbonic acid, and ( 2 ) esperiinent corresponds to a yield of about 947, of guanidine trinitride and carbon disulfide. Certain physical properties and chemical rethe theoretical, while the guanidine thiocyanate, actions of these salts have been studied, and a without correction for the amount unavoidably preliminary investigation of the reaction between left iti thc mother liquor, corresponds t o a yield guanidine carbonate and the free halogenoid, of 83y0 Nitrometric experiments upon sample!; azido-carbondisulfide, has been made. of one-tenth the weight previously used led to tht!
+
ITHACA, N. Y
i.5) Soderb'ick, .Ittn, 419, 217 (191'))
[ C O S T R I B V T I O S FROM THE CHEMICAL LAHORATORY OF THE JOHSS
RECEIVED A U G U ~28, T 1934
HOPKISSUNIVERSlTY]
The Thermal Decompoditioh of Organic Compounds from the Standpoint of Free Radicals. XI. The Methylene Radical B Y I?. 0. RICEAND A. L. GLASEBROOK'
In this paper we shall describe some experi- walls of the tube just beyond the tellurium mirror ments in which we have proved that under certain Since finethyl groups combine with metallic telconditions the methylene radical can be prepared lurium to form a red liquid, dimethyl ditelluride by thc thermal deecmpositibfi of diazomethane. CH3Tel'eCH3, which passes over into the liquid When this compound is carried in a current of air trap, it is very easy to distinguish between the ether or butane a t low pressures and is decom- two radicals. We found the methylene group posed? a t temperatures below about 550°, thc to he extremely toactive and to have a half life fragment6 pmdurred readily remove mirrors oi of the same order as that of the alkyl radicals, tellufium, selenium, antimony atid aYseHic whereas namely, of only a few thousandths of a second. zinc, cadmium, thallium, lead end bismuth mirrors It can be carried in a current d ether or butane are not i-efnoved.D We analyzed the produd. utlder our conditions up to 600"; above this formed by the combination of the fragments temperature but below the decomposition point with metallic tclluriutn and found it to be i. of the carrier gas it disappears and is replaced by polymer of teiluroforrnaldeliyde (HCH'Te),; thi:, methyl groups, is a rcd involatile solid which deposits on the ) < k n e ~ 4 Motors < Ca E'ehw, lBi30-lS3.L 11) A full d t s h l p t h t+ the tedtaque l k e d is p v e a in a paper lis Rirt Johnston and ftLermR ? h s JOURNAL, 64, 8628 (1932) Set. .LIW Klc' and
