AUGUST
1961
2981
NOTES
Solid State Ultraviolet Spectra W. H. WAGGONEEAND M. E. C-PBS' Recsived December 8'7,1960
The ultraviolet spectra of organic solids can be obtained by studying single crystals,a by examining the powder sublimed or otherwise deposited onto quartz platesla or absorbed onto silicic acid,' and by measuring the optical properties of a compacted sample in which the absorbing substance has been diluted with another material which is transparent in the spectral region being investigated.6 This latter technique has been employed extensively in the infrared region but neglected in the ultraviolet, although it was proposed originally for both. Recently we have found that the potassium bromide disk method is applicable to the study of organic compounds in the 220400 mp range. The spectra obtained from three widely divergent samples are shown in Figs. 1,2, and 3, together with the corresponding solution spectra. 2Gr.
--
,
00 200
2 50
300
I 350
4 00
WAVELENGTH, MU
Figure 3
The principal advantages of this method are that (1) only extremely small quantities of sample are required; (2) sample preparation is easy and rapid; (3) sample disks can be filed for future reference; and (4) good quality spectra containing some fine structure are obtaiqed. In addition, the spectra are free of solvent effects and should, therefore, be more amenable to theoretical interpretation.
7
p - BIOMOACETOPHENONE
I
151
EXPERIMENTAL
All melting points are uncorrected. Ultraviolet determinatiom were made with a Beckman DU quartz epectrophotometer. p-Bromoacet6phmonc waa obtained from Matheeon, Coleman, and Bell, and waa used without further treatment. melted a t 49-60' (lit.: m.p. 49-50.5"). ___i It Nitrosobenme waa prepared according to the directions of Vogel' and recrystallized three times from methanol to give an analytical sample, m.p. 67' (lit.: m.p. 67.548'). ~- bPhcnocylidencaxindbIc waa prepared by the method of Lindwall and Mac1ennan.O After recrystallization twice 350 400 from ethanol, it melted at 193' (lit.,' m.p. 193-194'). Sample prepardion. A . Absolute ethanol ~ o l u t i m a .Analytical solutions were prepared by standard volumetric techniques to give a final concentration of 0.02 mg. eample per ml. of absolute ethanol for all cornpounds examined. Absorption measurementa on these solutions were made with 1om. silica cella using absolute ethanol aa a blank. B. Potassium brontidc disks. Analytical grade potassium bromide and the sample compounds were separately ground in an agate mortar to approximately 200 meeh particle she. The appropriate weight of potassium bromide waa taken and the desired weight of sample added directly, ita weight being determined by difference from the weight of the mix-
I
\ 0 0
200
L LIQUID
. 250
3ao
WAVELENGTH, MU
Figure 1
I
J
(2) A. Kronenberger, Z . Physik, 63,494 (1930). ( 3 ) A. Kronenberger and P. Pringsheim, Z . Physik, 40,
200
250
300
WAVELENGTH, MU
350
4 GO
Figure 2
(l)(a) Present address: University of Tennessee, Knoxville, Tenn. (b) This paper is based on an M.S. dissertation by M.E.C., University of Georgia, 1959.
75 (1927). ( 4 ) M. Robin, J. Chem. Edw., 33,526 (1956). (5) M. M. Stimson and M. J. O'Donnell, J. Am. Soc., 74,1805 (1952). (6) R. Adams and C. R. N o h , Org. S&m, Vol. I, 110 (1941).
Chem. Coll.
(7) A. I. Vogel, Practical Organie Chemistry,3rd ed., Longmane, Green and Co., New York, 1950, p. 630. (8) E. Bamberger and L. Storch, Ber., 26, 473 (1893). (9) €I. G. Lindwall and J. S. Rlaclennnn, J. Am. Chem.
Sac.,54,4739 (1932).
2982
POL. 26
NOTES
ture.'O The mixture wm then thoroughly blended by further grinding together, placed in a Perkin-Elmer potassium bromide evacuable die, and pressed under approximately 25,000 p.s.i. (gauge) for 3 min. Spectral measurements were made using the disk holder described by Waggoner" with a similarly prepared 400 mg. potmiurn bromide disk for a blank.
c; T'
COCH3
I
-
0COCH,
CHEMISTRY DEPARTMENT OF GEORGIA UKIVERSITY ATEENS, GA.
Fe
II
&AH
I
(10) The final compositions of the disks were: 0.05 mg. of p-bromoacetophenone, 0.3 mg. of nitrosobenzene, 0.2 mg. of 3-phenacylideneoxindole, each in 400 mg. of potassium bromide. (11) W. H. Waggoner, ChemistAnulyst, 48,80 (1959).
CHCH3
I1
+
NaBH4
CFHCHCHS
Cyclic Ether Formation by
Bis[(l-hydroxyethyl)cyclopentadienyl]iron EUGENE c. WINSLOW
AND
w.
EDWARD BREWSTER
- H20
Fe
I
&AH
I
\
P
CHCHB
Received September SO, 1960
The preparation of divinylferrocene was attempted in this laboratory by the use of diacetylferrocene (I) as a starting material. This was reduced to form bis [ (1-hydroxyethyl) cyclopentadienyl]iron (11).This compound was previouslyreported as melting at69-71 O.l Infrared data and other evidence indicate that the compound produced by reduction of diacetylferrocene ~1ith sodium borohydride in this laboratory is in fact bis [ (1-hydroxyethy1)cyclopentatlienylliron I1 and has a melting point, of 105106". The attempted dehydration of this dialcohol (11) produced B cyclic ether (111) between the side chains of the two cyclopentadiene rings of ferrocene rather than the desired divinyl ferrocene. The infrared spectrum of I1 shows a strong hydroxy bond a t 3.10 p. The carbonyl bond is absent in the spectrum. ildditional significant bonds appears at '7.35, 7.60, 9.10, and 12.41 p. The infrared spectrum of the cyclic ether I11 shows :t disappearance of the hydroxyl bonds. An ether bond a t 8.8 B can be cited as evidence for a cyclic ether. Other bonds appear a t 7.68, 9.36, 9.88, 11.95, and 12.35 p.
I
Fe
I11 lyze the salt formed in the reaction. The product was then extracted with ether. The ether was removed and a yellow crystalline solid was obtained, which was recrystallized from methanol The yield was 14.4 g. (53.4%), m.p. 105-106'. Anal. Calcd. for ClaHleOt Fe: C, 61.31; H, 6.57. Found: C, 61.36; H, 6.72. Preparation of 1,i'-diethyl-a,a'-epoqbiscyclopentadienyliron (IZ)(III).In a 1-1. flask, fitted with a reflux condenser, wafi placed 27.0 g. (0.0985 mole) of diacetylferrocene, 7.56 g. (0.2 mole) of sodium boroh>-dritle, and 200 nil. of isopropyl alcohol. The mixture was refluxed for 5 hr. on a steam hath. The solution was tlieii cv:qJomted to dryness by 1nea11sof an air stream and 100 ml. of water containing 5 ml. of glacial acetic acid was added to the residue to hydrolyzv t,he salt formed in the reaction. The product was extracted m-ith ether. The ether was evaporated and a yellow crystallinc solid was obtained. The product was recrystallized from methanol. The yield was 11.2 g. (44.570), m.p. 95-98". Anal. Calcd. for CllH1& Fe: C, 65.52; H, 6.25. Found: C, 65.53; 13, 6.42.
Acknowledgment. This u w k was carried out :LS a portion of work on a contract mit)h t,he U. S. Army Quatermaster Corps. UNIVERSITY OF RHOUE ISLAND KINGSTON, R. I. (2) R. B. Woodwitrd, bZ. Rosenblum, and hf C. Whiting, .T. Am. Chem. Soc., 74, 3458 (1952).
bXPERIMENfl'AI~
Preparation of 2,6-L)ioxocyclohexarlepropiollic
Diacetylferrocene was preparrcl IJY followiiig the I'roocdrirc of Woodward ( 2 ) . Acid and 6-Oxoazelaic Acid from Glutaric Preparation of bis[(l-hydroz~~ethyZ)cyclopetitadienyl]iroi~. Anhydride In a liter one-neck flask, fitted with a reflux condenser, was placed 27.0 g. (0.0985 mole) of diacetyl ferrocene, 7.56 g. (0.2 mole) of sodium borohydride, and 200 ml. of isopropyl RALPHF. GILBY,JR. alcohol. The mixture was refluxed for 5 hr. on a steam bath. The solution was then evaporated to dryness by means of Received October 5, 1960 an air stream and water was added to the residue to hydro(1) R. J. Graham et al., J . A m , Chern. Soc., 79, 3416 (1957).
The preparation of 6-oxoaselaic acid (boxononanedioic acid) from discdoacetone dicarboxylic
