June 5 , 1959
C O m r U N I C A T I O N S TO THE
Synthetic Analogs of Busycon Mucus.-Broadly speaking a synthetic analog must be constituted of two acidic polyelectrolytes linked by a calcium ion. I t should possess the viscosity properties of mucus as well as the unique characteristics2 of "elastic recoil" and "stress-fibrilation." Two attempts were made to simulate this mucus behavior by reproducing synthetically these basic structural elements. First, a 37, solution of polyacrylic acid ([VI 0.8) in water was mixed with calcium carbonate forming a product with 7.61 acrylic acid residues per calcium atom. The pertinent physical properties were qualitatively very similar to those of Busycon mucus. AIoreover, it was found that addition of 0.5 S NaCl caused a decrease in these properties that was also reminiscent of Busycon mucus behavior.2 Finally, a somewhat closer analog was prepared
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2905
from poly-2-aminoglucose bisulfate and polyacrylic acid. A solution of partially acid degraded chitosan was treated with an excess of sodium bisulfate, dialyzed and the volume subsequently adjusted to an 8% solution. This solution was stirred into an equal volume of 3y0 aqueous polyacrylic acid and followed by the addition of 2 ml. of 0.1 N Ca(OH)2. The fresh mixture evidenced the typical behavior of Busycon niucus but with time further cross linking appears to have occurred with accompanying gelation. Acknowledgment.-We wish to thank Professor R. R . Ronkin of the Department of Biological Sciences of the University of Delaware for many helpful discussions on mucus and Dr. P. Hamilton of the Alfred I. du Pont Institute for his kind help in the ion exchange chromatographic analysis. SEWARK, DELAWARE
C 0 M M U N I C A T I 0 N S T O T H E EDITOR A NEW SYNTHESIS OF IRONES
Pinonone (111) and acetylene in the presence of sodium acetylide in liquid ammonia gave 3Since the isolation of irone from orris root by (2,2,3-trimethylcyclobutyl) -but-1-yn-3-01 (I V) (cis Tiemann and Kriiger' in 1893, various syntheses and trans mixture) in almost quantitative yield, have been attempted. Studies of the structure of b.p. 74' (8 mni.); 1.4667; a Z 5 D -4'. Anal. irone by Ruzicka and co-workers2 in 1933 were Calcd. CllHI80: C, 79.46; H, 10.91. Found: followed in 1940 by their synthesis of 6-methylio- C, 79.76; H, 11.02. The butynol (IV) and ethyl acetoacetate; a t nones2 later identified with the irones. In 1947 Naves and co-workers3 reported a practical syn- 178-180' afforded cyclobutyl isomers of irone. thesis of 3-methylcitrals and 3-methyllinalool 2- (2,2,3-trimethylcyclobutyl)-hepta-~~4-dien-~-one, from which irone could be made. ilnother ap- referred to as cyclobutirones (17) in 65% yield, proach was made in 1952 by Griitter, Helg and b.p. 95-105' (0.5 mm.) ; n 2 0 ~1.5080-1.5280. Schinz4 using thujacetone for the synthesis of 3- At least four main isomers were identified by gasmethylcitrals and their isomers. More recently liquid partition chromatography. The most stable the total synthesis of 5,6-dimethyl-5-hepten-2-oneof the isomers was isolated from the mixture as the from methyl isopropenyl ketone, acetylene and semicarbazone, m.p. 202-203' (ethanol). (Found : diketene led to a marked improvement in the C, 67.92; H, 9.11; N, 15.87). 2,4-Dinitrophenylsynthesis of irone in about eight s t e p 6 hydrazone, m.p. 198-199' (ethanol). (Found: We wish to report a new synthesis of irones C, 62.16; H, 6.62; X, 14.47). from a-pinene involving five steps : a-Pinene The mixture of cyclobutirones (V) was rearranged (I) was ozonized to yield 65-70y0 cis-pinonic to irone isomers (VI) by treatment for several 1.4610; hours with 85% phosphoric acid a t 25' in over 50% aldehyde ( I I ) , b.p. 92' (1.5 mm.); n 2 ( ' ~ 2% 40'; purity 9!3% by oxiniation, and a small amount of pinonic acid. Decarbonylation of (11) by means of palladium catalyst6 a t about 200' afforded the new ketone, (111) pinonone, 1-acetyl-2,2,3-trimethylcyclobutane (cis and trans mixture) in 80% yield, b.p. 53' .I (9 m m . ) ; %?OD 1.4410; semicarbazone of probable I ,OH rzs-isomer, m.p. 197-198'. (Found: C, 60.92; CH,COCH,COOR H, 9.84; E,21.40) ; 2,4-dinitrophenylhydrazone, \I/ m.p. 201-202' (Found: C, 56.36; H, 6.38; N, V IV 17.63).
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(1) F. Tiemann and P. Kriiger, Be?., 26, 2679 (1893). ( 2 ) L. Ruzicka, C. F. Seidel and H. Schinz, Hela. Chiin. Acta, 16, 1143 (1933); L. Ruzicka and H. Schinz, i b i d . , 23, 959 (1940). (3) Y . R . Naves, A. V. Grampoloff and P. Bachmann, i b i d . , 30, 599 (1947). (4) H. Griitter, R . Helg a n d H. Schinz, ibid., 35, 771 (1952). ( 6 ) W. Kimel, J. D. Surmatis, J. Weber, G. 0. Chase, PI'. W. Sax a n d 4.O f n e r , J . O Y C~h c ; n . . 22, 1611 (1957). I l i ) 11.
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C)OhlMUNICATIONS TO THE
EDITOR
Vol. 81
yield, b.p. 74-83' (0.3 xnm.); n2O~1.5002; @D -15'. The irone mixture was shown by infrared and gas-liquid partition chromatography to consist of about 57% a-neoisoirone8 (4-phenylsemic a r b a ~ o n em.p. , ~ 174-175' from ethanol. (Found : C, 74.02; H , S.43.)), 10.5% a-irone; 8.2% pirone, S.4% lights and 16% high boiling isomer (4-phenylsemicarbazone, m.p. 144' from ethanol (Found: C, 74.03; H , 8.18)). The structure of the latter isomer is being elucidated.
added to a synthetic mixture containing the metal ions and acid is recovered almost quantitatively under the same conditions for distillation. When pyrophosphate in excess is added to the mixture after reaction and the solution is subjected to continuous extraction with ether, in 6 hours 6G-70y0 of the fumaric acid is recovered, this recovery being identical to that observed when R F H + + rather than RFCH3++ is the oxidant. The extract however contains very little alcohol (it should be noted that the half-ester would (8) T h e structure of a-neoisoirone was established by Y.R . Naves and P. Ardizio, Bull. SOL.Chbz. Fvancc, 1419 (1955). respond to the test for CHJOH). If the reaction ( 9 ) Pseudoirone from Hoffmann-La Roche, Inc.,s Kutley, N. J., mixture then is refluxed to complete the cornplexing gave upon cyclization with 85% phosphoric acid 16% a-irone, 10 5 % by pyrophosphate, the alcohol can be recovered 8-irone, 7 % lights, and G G . 5 % a-neoisoirone (4-phenylsemicarbazone. essentially quantitatively on distillation. m p. 114' from ethanol). Mixed melting point with 4-phenylsemicarbazone of a-neoisoirone from cyclobutirone, 174'. Both derivatives From these and related observations, we conclude show identical infrared spectra in K B r pellets. that ester hydrolysis accompanies electron transfer THE GIVAUDAN CORPORATION (to account for the appearance of acid and the DELBWANNA, KEIV JERSEY H. E. ESCHINAZI extractability of fumaric acid) and that the CH30H RECEIVED APRIL 1, 1959 is left cobrdinated to Cr(II1) (to account for the holdback of alcohol by the solution). Blank SUBSTITUTION COUPLED TO ELECTRON experiments prove that CH,OH in solution does TRANSFER' not become associated with chromium when Cr++Sir: aq. reacts with RFH++. Thus we conclude further Rate comparisons2 made for a series of pentam- that transfer of alcohol to chromium must be direct, minecobaltic complexes reacting with Cr++ aq. and therefore that C r f + attacks the ester end of suggest that when appropriate bridging groups are the fumarato ligand. associated with Co(III), electron transfer takes GEORGE HERBERT JOSES LAD. R. T. &I. FRASER place by remote attack of Cr++, the electron flowing USIVERSITYOF CHICAGO D. I(.SEBERA ILL H. TAUBE through the bond system of the bridging group. CHICAGO, RECEIVED FEBRUARY 27, 1959 The results reported now seem to constitute definite proof for this conclusion.
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DIFLUOROAMINE'
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During the reaction of nitrogen trifluoride with arsenic a t elevated temperatures (250-300') to produce tetrafluorohydrazine2 small amounts of (to be subsequently represented as RFCH3++) difluoroamine were produced. reacts with Cr++aq. a t almost the same rate as The identity of difluoroamine has been estabdoes the corresponding complex with fumaric acid lished. Its molecular weight by vapor density in place of the half-ester. In both systems, good measurements is 52 (calculated 53). The mass stoichiometry for the oxidation-reduction process spectrum of difluoroamine given in Table I was is observed, one Co++aq. (and 5NH4+)being formed obtained on a Consolidated Electrodynamics for each Cr++aq. which reacts. Model 620 Mass Spectrometer and is consistent Now it should be noted that remote attack by with the formula HNF2. Cr++aq. on the half-ester will leave both Cr(II1) TABLEI and CH3 attached to the remote carboxyl. The resulting structure would not be stable, so t h a t ester FRAGMEXTATIOW PATTERN OF HI\-F2 hydrolysis may be expected to ensue on electron ni/e Ion Pattern, % transfer. We cite evidence that this reaction does 53 HSFz 100 indeed take place. When Cr++aq. in equivalent 52 SFL X i amount is added to 0.01 dl RFCH3++ in the 84 HNF+ 99 5 presence of 0.1 A f HC104, and the solution imme33 SF+ 4i 4 diately after reaction is titrated to pH 4.5 with 20 IIF 4 0 standard alkali, we observe that acid has been 5 2 19 F' produced equivalent in amount to the complex 15 SH X i which has reacted. When such mixtures after 11 S+ 33 0 reaction are distilled a t 4', variable amounts of The infrared absorption spectrum of difluoroCHIOH are detected in the distillate, but comprising only 2 to 7y0 of the total CHzOH. In a amine consists of strong doublets a t 7.0, 7.8, blank experiment, similar in every respect except 10.2 and a triplet a t 1 1 . 2 ~ . The n.m.r. proton specthat Cr+++aq. is used in place of Cr++aq., no trum consists of a triplet as would be expected CHlOH is found in the distillate. Free CH,OH from a proton spin-spin coupling with two equivalent fluorine nuclei. The center of the triplet is bCH3
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(1) This work is supported by the Atomic Energy Commission under COntrdCt AT(l1-1)-378 I ? ) P K Sehera and €1 T a u h r t o I>P p i i h l i - h d (rlwrrihed in p i r t i n i iil I ( 1 , 37, ~ 124 ( I ' i i q i )
(1) Army Ordnance Contract DA-01-021-ORD-5135 (2) C R Colbura and A Kennedy. THIS J O U R N A L , 8 0 , 5004 (i%Rl
