Nov., 1943
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found when the values of log log (Io/I)were plotted against the frequency or reciprocal wave length. Separate isomerization experiments indicated that the "flavoxanthinlike carotene," which apparently is not identical with a
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similar carotene of yellow corn,6containsthe stable or Irun: form of the Polyene chromophoric group. (6) White, Zscheile and Brunson,
Trlls J O U R N A L , 64, 2003 (1942)
STANFORD UNIVERSITY, CALIF RECEIVEDM A Y10, 1943
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all the sodium is dissolved or more sodium is added until the A Zn salt spectrum is cwnpletely I n 1935 Rothemund' described the preparation replaced by a new one consisting of three bands of tetraphenylporphin from pyrrole and benzalde- 620 mp, 600 mp and 559 mp. This solution shows hyde and claimed the separation of two isomers a very powerful red fluorescence. which he believed to be due to the two possible 4. The solution from 3 is washed with water, positions of the pyrrole acid hydrogen atoms. then with 6 N hydrochloric acid which removes the This work was continued by Aronoff and Calvin2 Zn and converts the free base irito the c ! c q green in which a more c6mplete separation was achieved hydrochloride (in the n-hexanol). This is then by chromatographic adsorption. It was also washed with water until all thi: hydrochloric acid shown that not only two but probably six dif- is removed, leaving a solution of the flee base (Bj ferent porphyrin-like substances were formed in in the n-hexanol. the reaction. 5 . The solution from 4 is converted into Cu Recently an examination of their spectra and salt as described in 1and shows two approximately a comparison with the spectra of naturally and equally intense bands 536 inp and til5 inp which synthetically derived porphyrins and chlorins: is the spectruni of the H Cu salt. (jpercitions 4 indicated that the spectra of the first two most and 5 must be done as nearly in the abscmcr (ti abundant materials obtained in the tetraphenyl- oxygen as possible. porphin synthesis, called A (most abundant) and 6. Upon blowing oxygen throuyli the solutirvrr B (next most abundant) might be rclated as par.- obtained in 5 for several rninutcs :ii!d warming, phyrin to chlorin, respectively. If this be so it the 615 m p band disappears a.ncl, after a w:ishing should be possible to convert B into .I by oxir!a with water, the spectrum is that of the pure -1C u tion and A into B by reduction. This w r liavc salt. The Cu salt of B obtuiiied clironiatosucceeded in doing in the following inanner. 'The graphing the original porph>-riii pre;Jara tion has spectrum of the Cu salt was used as identification also been oxidized by oxygen tt, Xive thr A C'U since the difference there is greater and easier to salt. observe than in the free base. Thus we have shown that A anti 1.; a r c related 1. A sample A (several mg.) is dissolved in by oxidation and reduction and suggest t h a t I3 is about 15 cc. of n-hexanol. Several crystals c;f tetraphenylchlorin. cupric acetate are added and the solution is The work is being repeated cluaniit;ttively aiid brought to a boil, cooled, and washed thoroughly will be so reported later, together 1c.it.h o1)serwwith 6 AT hydrochloric acid and then with water. tions on the intermediate products in thr oxid:!The hesanol solution (after drying with sodium tiori and reduction. sulfate) then shows only the spectrum of the CLI CHEMISTRY LADORATORY $1. CAL.VIN salt of -1,i. e., a single intense band at 5% m. UNIVERSITY OF CALIFORNIA R. €1. HALL CALIFORNIA s .4ROSOFf 2 . Another sample (several mg.) of A is dis- BERKELEY, RECEIVED OCTOBEK 13, 191:; solved in 15 cc. of n-hesanol and several crystals (ca. ten-fold excess) of zinc acetate added and the solution brought to a boil. After cooling, the ROTENONE IN THE YAM BEAN (PACHYRRHIZUS solution is washed with dilute acetic acid arid with EROSUS) water and dried with sodium sulfate. This solu- Sir. tion now shows the spectrum of the Zn salt of -4 The question of the possible occurrence of t o t t i which seems to consist of three bands in the fol none in the yam bean is of particular intcrcst belowing order of intensity: 555 mp, 50G mp arid cause this plant has recently been suggested' a s a 31s mp. 3. Thc- solution of the A Zn salt is now boiled source of insecticidal material to s u p p l ~ m c n tthe for two minutcs sild a piece of metallic sodium usual rotenone-bearing insecticides, Tile w c d 5 (5 min.) dropped in arid the boiling continued until have long been known to be toxic to insects .md fish, arid Hmang2 has reported the occurrci:icis of
Sir:
(1) Hansberry dnd Lee, J . Ecox. Enlornol., $ 6 , 351 i1013) (2) Hwang, Kwangsl A g i . , 9, 269 ( 1 9 l l i $ i n Chinese:, summar) Reo. A p p l i e d Enlonml.. SOA, 41R (19421
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rotenone, but only on the basis of' a color test not specific for rotenone itself. Camson3has obtained a crystalline substance resenibling rotenone from a carbon tetrachloriclc solution oi the oil-free resin from the seeds. Two I;g. of ground yarn bran needs from Mexicc! were exLractctl wiih ether, the ether removed, a i d the iiisecticidally active resin (1.47;) separated froin the large atiiount of fatty oil (26.7c/c,j by partition between 90% acetic acid and petroleuiii ether. The oil-free resin in heiizene solution was iractionatetl by clironiatographic ndsorption on nlut~iina. The fraction giving a strong Goodhue' red color test deposited from benzene solution Sevcrdl crops of crystalline material giving little or no color test. The benzene was removed from the remaining solution, and the residue taken up in hot carbon tetrachloride. X heterogeneous brownish deposit formed after cotling overnight, arid was removed. On scratching the flask walls or seeding with rotenone-carbon tetrachloride solvate, a. mass of white needles was depositei, siniilx iri appearance to the rotenone solvate. Wheii warmed with alcohol, these needles were converted rapidly to thin plates like those of rotenone. 'The compound w : identified ~ as rotenone by a ni. p. of 1~64-~1&5'(cor.) both alone a i d in atlmixture with kiiwvii rotciiorie ; the formation of' a dehydro compound of t i l . 1). 222' ; optical rotation in 17, Ixiizeiie soltitiem [ u ] ? ~ D - 233'; quantitative Goodhrie and M e y r a t i d qualitative 1)urhaiii c- agreeiiieiit with the wrresponding properties ( i f authentic rotenone. Tlie isolated rotctione atiiountcd to about 0.1% (,I tlie origiiial I)eai!s. 'i'lie total material giving t tie red colc~rtcst iii thic s:tniple was O.135&,cal,111atcd as rotci:orie. I t is therdore probable (list rc.itenoiic itself accounts for a substantial iwq)ortioii of the color tests reported by previous wvrkers. Some samples have beeii reported to havc a much higher content of color-producing inaterial tha:i the sample used in this work. Rotenone does iiot account fully for either the toxicity or the red color test of tlie yam bean. A riunibcr of other compounds of yet unknown constitution also have been isolated, some giving the color test, and some showiiig c1efiiiit.e toxicity to insects. Investigation of these conipounds is iiow in progress.
VOI.
ti#-,
would yield cyclohexadienes and cyc1ohex:inol. It has now been found, however, that l,&eporycyclohexane is predominantly forti!crl. I t h a also been observed that by p:using :t soliitioii of /rans-l,4-cyclohexanrdioIo i w :ic!i\,:ct.citl :111.1nii11;i a t 27,5", 7$4 of 1,d-eposycyc.lrihe~~n~ is f o i - J : i i . i i , while the cis ison:cr under similar cmilitims k: -,,\.e< only 28Yh of the epoxidc. 'The type ~i~I~:(.i1t, contact agent, and temperature used rxen influence upon the yield of the epc!xidt. 1,4-Epoxycyclohexane boils :it 120. I ;ii( I mm.), d2"4 0.9707, 1 . 4 4 i i ! .ll% ? i . i ) ; j , .1 /;(!L. Calcd. for CcHloO: C, 73.4i; H, l!j.:?O. i;ouiitl: C, 74.10; 13, 10.14. I t is soluble in tlie U S U : ~organic solvents and is partially soluble i n water, with which it forms an azeotropic niistiire boiliiiy a t 90'. It is soluble in -kO--60'z;i sulfuric acid from which it niay be reco eti 1)y tlilution 7,Yitli water. On heating with 1 bromide fmns-l,3-dibromo "
(1) V. K. Ipatieff, "Catalytic React) Temperatures," The MacMillan Cimpzi
CHPMISI R Y IJEPAKTMENT ORTII\YI..Sl E K S ~ ~ I I V P R S IY. 1
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