Jan. 20, 1955
CONJUGATED POLYENES AND ~POLYPHENYLS
passed through a solution of 2 g. of the monomer dissolved in 50 ml. of ethyl acetate until the reaction was complete. The reaction mixture was kept a t Dry Ice temperatures t o prevent the loss of any formaldehyde which might be liberated during the course of the reaction. The reaction time of each experiment was approximately 45 minutes. Decomposition of the ozonide was carried out by a procedure similar to that of Hurd and BlanchardZ1in which the ozonide was poured into 50 ml. of water and 10 g. of zinc dust and the mixture mechanically shaken for 20 minutes. The zinc dust was collected on a filter and the water layer separated from the organic layer in a separatory funnel. To the former there was added a solution of 36.4 g. (0.026 mole) of methone dissolved in 25 ml. of 50% ethanol and to the latter there was added a solution of 2.57 g. (0.13 mole) of 2,4dinitrophenylhydrazine dissolved in 20 ml. of concentrated sulfuric acid t o which was added 20 ml. of water. Crystals separated almost immediately in all experiments. The methone derivatives were recrystallized from 95% ethanol and ethyl acetate mixtures. The melting points and yields of the derivatives of the ozonide decomposition products for the three monomers were as follows: a-ethylstyrene, (21) C. D. Hurd and C. A. Blancbard, TRISJOURNAL., 71, 1461 (1950).
[CONTRIBUTION FROM
INSTITUTE O F
373
methone derivative, m.p. 0189°, 59%; 2,4-dinitrophenylhydrazone, m.p. 190-191 , 45% (formaldehyde dimethone, m.p. 189’; ethyl phenyl ketone 2,4-dinitrophenylhydrazone, 191O)**; a-n-propylstyrene, methone derivative m.p. 188.5-189’, 52%; 2,4dinitrophenylhydrazone, m.p. 189-190°, 57% (n-propyl phenyl ketone, 2,4dinitrophenylhydrazone, m.p. 188 or 190°)en; a-isopropylstyrene, methone derivative, m.p. 189’. 53%; 2,4-dinitrophenylhydrazone, m.p. 157-158’, 62% (isopropylphenyl ketone, 2 , 4 dinitrophenylhydrazone, m .p. 163O. zx A mixture of methone derivatives from the ozonide decomposition products of the a-ethyl, a-propyl and a-isopropylstyrenes were mixed together with formaldehyde dimethone, m.p. 189’, with no depression of the melting point.
Acknowledgment.--We wish to thank the Office of Naval Research, Contract No. NR-343 (00) for their generous support of this work. (22) E. H. Huntress and S. P. Mulliken, “IdentiBcation of Pure Organic Compounds,” John Wiley and Sons, Inc., New York, N. Y., 1941.
BROOKLYN, N. Y.
POLYTECHNICS,
OSAKA
CITY UNIVERSITY]
Absorption Spectra and Chemical Structures. I. Conjugated Polyenes and p-Polyphenyls BY K E N ZHIRAYAMA ~ RECEIVED JULY 16, 1953 A study is presented of the dependence of spectral absorption on structure in polyene derivatives and p-polyphenyls. In this paper conjugation of similar chromophoric groups is considered. I t is shown that the wave length of the first absorption maximum may be expressed by (Am.=)* = A B C N ,where N is a proposed index defined by number of conjugated homochromophores, number and type of substituents, and of spectroscopically effective structures.
-
It has long been known that definite relationships exist between the structure of organic molecules and their visible and ultraviolet absorption spectra; empirical and theoretical formulas have been advanced relating the wave length of the first absorption maximum with the number of conjugated chromophoric groups. But the values calculated by these formulas do not always agree satisfactorily with the observed values. However, we have found that the wave lengths predicted by equation 1,l:in which n is the number of conjugated groups, agreed well with the observed wave lengths of the first absorption maximum. (Anlaa)z = u
+ B ( l - C”) = A (A = a +B)
- BC“
(1)
The adequacy of this functional relationship is shown in the following examdes. a,o-Diphenylpolyenes : =C H( = C H) . ~ For benzene solutions, equation 2 holds
-
(X&:)*
= (38.08
- 30.81
I n spite of the comparative agreement between the values in column b and those observed, equation 3 is not valid because the relation between X 2 and n is obviously not linear‘ (see Fig. 1). TABLE I ABSORPTIONMAXIMA OF DIPHENYLPO POLYENES
IN
BEN-
ZENE
Obsd.,‘ mr
n
Calcd. a, mr
b Bmp
c. mr
d , mr
1 2 3 4 5 6 7
306 305 310 311 356 335 334 334 357 294 358 339 360 358 412 384 382.5 366 380 445 403 402 400 480 395 420 420 416 420 505 438 435 435.5 438.5 532 a K. W. Hawser, R. Kuhn and A. Smakula, Z . p h y s i k . Chem , B29, 384 (1935).
.
a,a,w,w-Tetraphenylpolyenes:
X 0.934“) X lo4 mp* (2)
The values in column a of Table I calculated by equation 2 are more satisfactory than those in col- Equation 4 holds for this series; the agreement beumn b calculated by Lewis and Calvin’s formula 32 tween the values for the parameter C in equations 2 (C 0.934) and 4 (C 0.935) should be noted. The (A,)Z = A + Bn (3) (4) Nevertheless, since the numerical disagreement between the or the values in columns t and d given by Dewar’s values obtained by equations 2 and 3 are so slight, it m a y be conceded LCAO MO methodss that the results obtained with the Lewis and Calvin equation are supe(1) One possible justification for the functional relation (1) will be demonstrated in the appendix. (2) G. N. Lewis and M. Calvin, Chem. Reus., 25, 273 (1939). (3) M. J. S. Dewar, J . Chem. SOC.,3544 (1952).
rior in the sense that the latter was derived on the basis of a physically signiEcant model. Thus far, our equation has been described merely as an empirical relation. In the appendix, however, a justification of the new relation is given.
Vol. 77
K E N ZHIRAYAMA ~
374
of the substituents must be considered. -1lthough there are structural differences between chromophoric and auxochromic groups, experimentally the differences may be correlated with the amount of the wave length shift. Therefore for auxochromic substituted polyenes, the approximate value of Amax may be calculated by adding the effect of the substituents to n. For this purpose, the ratio of the auxochromic substituent effect to the ethylene chromophore effect was determined for a number of substituted butadienes (Table VI, 2, 3 , 9, 10 and 12-16), with the assumption that the curve X2-n is approximately a straight line for a small range of n, e.g., 2 5 n 5 3 (see Fig. 2 ) . These ratios are given in Table IV.
18
16 . *
s
.
x
l4
1
4 5 6 7 N. 1.-First absorption maxima of diphenylpolyenes ' ( X ~ ~= ~ (38.08-30.81 ~ ) 2 X 0.934") X l o 4 m,u2.
Fig
2
3
values for Amax in Table I1 calculated from equation 4 are in excellent agreement with the experimental values. (XCt:X)z = (4034 - 32.71 X 0.935"i) X lo4 mwz (4)
TABLE IV RATIOSOF BATHOCHROMIC EFFECTS OF ALKYL AND aHYDROXY ALKYL AUXOCHROMSS TO THAT OF ETHYLENE CHROMOPHORE R
0.13 .17 .09 a-Hydroxyalkyl A .15 R = substituent in a- or w-position; R' = substituent
R' I
a
in
01-
or w-position in
TABLEI1 position other than ABSORPTION MAXIMA OF CY,CY,~,U-TETRAPHENYLPOLYENES IN a- or w-position. CYCLOHEXANE Obsd.," mp
?I
Ratio
Suhstituents"
Alkyl
01
">
C=C. . ,; I = substituent iri R' or w ; A = a-hydroxyalkyl group in
Calcd., mp
312.5 342.5
312 343 . . 369 3 4 392 392 5 411.5 112 6 430 430 0 Observed wave lengths were calculated from wave numbers observed by G. Kortiim and G. Dreesen, Chem. Ber., 84, 182 (1951). 1
0
i
p-Polyphenyls : Equation 1 is also applicable to this conjugation series. The agreement between the experimental values for Amax and those calculated (column a, Table 111)from equation 5 is quite good. (Xom",'~)4= (10.97
- 4.66
X 0.661") X l o 4 mpa ( 5 )
The values in column b were calculated by Dewar3by the LCAO MO method. TABLE 111 ARSORPTION MAXIMAOF p-POLYPHENYLS
IN
CHLOROFORhl
Calcd. 7,
Obsd.,' m p
a , mp
2.5 3.0 N. Fig. 2.-Auxochrornic effect of alkyl substituents in hutadiene derivatives.
2.0
b , mp
251 257 251.5 281 296 1 280 299 302 2 300 310 310 3 310 317.5 311 4 317.5 a Experimental data from E. A. Braude, Ann. Repts. on Progr. Chem. (Chem. Soc. London), 42, 111 (1945). 0
Polyenes with Auxochromic Substituents.-For polyenes with auxochromic substituents, the effect
1. 2. 3. 4.
5. 6. 7. 8.
9. 10.
Kumbers as in Tahle VI Butadiene (BD). . . . . . 2-MeBD.. . . . . . . . . . . 1-MeBD.. . . . . . . . . . . l-CMe20H-BD.. . . . . / ~ - c H ~ o H - B D.. . . . . . 11-CHMeOH-BD . . . . . 2,3-DiMeBD.. . . . . . . 1,4-DiMeBD.. . . . . . . 1,1,3-TriMeBD.. . . . . 1,1,4,4-TetraMeBD. .. Hexatriene
1
10 2 16 14 15 13 3 12 9
375
CONJUGATED POLYENES AND ~ P O L Y P H E N Y I ~ S
Jan. 20, 1953
TABLE V ABSORPTION MAXIMUM OF POLYENES IN ALCOHOL No.
Compound
1 2 3 4
CH~=CH-CH=CH-CH=CHZ CHz=CMe-CH=CH-CH=CHz Me-CH=CH-CH=CH-CMe=CHz Me2C=CH-CH=CH-CMe-CH2
5 G
Me-CH=CH-CH=CHCH=CHCHzOH M~-CH=CH-CH=CHCH=CHCHOH-= Me-CH=CH-CH=CHCH=CHCHOH-Ph
7 8 9 10 11
3 3 3 3
0 1 2 3 1 1 1 2 2 2
3
2
1
3 3 3 3 3 3
Me-CH=CH-CH=CHCMe=CHCH2OH
Me-CH=CH-CH=CHCMe=CHCHOH 4 r(CHz)aCH=C-CH=CHCH=CHCHOH-Me
Subst. and structure R A E p
n
3
r(CH2)3CMe2CH=C-( CH=CH)zCHOH-Me
0 0 0 0 1
0 0 0 0 0
1
o
1 1 1 1
xdo.
rl
0 0 0 0
0 0 0 0 0 0 0 0 0 0
0
0
N 3.0
mal’
Obsd.
ma
Calcd.
3.1 3.2 3.3 3.2 3.2
257” 257“ 261b 270b 265“ 26gd
256 260.5 265 270 265 265
3.2 3.3 3.3 3.3
269‘ 268‘ 26Sd 270d
265 270 270 270
3.3
268.
270
12 CH*=CH-CH=CH-CH=CH-CH=CH2 4 0 0 0 0 4.0 302” 299 5 4 1 1 0 0 4.2 310’ 307 13 Me-(CH=CH)d--CH2OH 0 0 0 5.2 343’ 14 Me-(CH=CH)5-Me 5 2 341 15 Dihydrobixin 8 6 0 0 425 423 0 8.6 16 Dihydromethylbixin 8 6 0 8 6 424 423 0 0 8 6 0 0 0 8.6 17 Dihydro-P-carotenone oxime 426 428 18 a-Apo-2-carotenol 8 5 1 0 0 8.6 423 423 19 5,6-Dihydro-a-carotene 9 6 0 0 0 9.0 443 44 1 0 0 11 8 0 11.8 472 20 Lycopene 473 21 Lycoxanthin 11 8 0 0 0 11.8 474 473 22 Lycophyll 11 8 0 0 0 11.8 474 473 23 Decapreno-E1-carotene 13 8 0 0 0 13.8 494h 496 24 Rhodoviolascin 13 8 0 0 0 13.8 491 496 25 Eloxanthin (xanthophyll epoxide?) 9 5 0 1 0 9.7 445 442 26 Cryptoxantin diepoxide 9 4 0 2 0 9.8 442 444 27 Violaxanthin (zeaxanthin diepoxide?) 9 4 0 2 442.5 444 0 9.8 28 Vitamin AI 5 5 1 0 1 4.8 328’ 328 29 8-Apo-2-carotenol 9 7 1 0 1 9.0 426 430 30 5,6-Dihydro-P-carotene 10 8 0 0 448 447 1 10.0 31 Lutein (xanthophyll) 10 8 0 0 1 10.0 446.5 447 32 Helenien (xanthophyll dipalmitate) 10 8 0 0 1 10.0 448 447 33 Capsanthol 10 7 1 0 1 10.0 448 447 34 Cryptoxanthin monoepoxide 10 7 0 1 1 10.1 449 449 35 Antheraxanthin 10 7 0 1 1 10.1 450 449 36 Gazaniaxanthin 11 9 0 0 1 11.1 462 463.5 37 Rubixanthin 11 9 0 0 1 11.1 463 463.5 38 Celaxanthin 13 10 0 0 1 13.2 488 490 39 Cryptoxanthin 11 10 0 0 2 10 4 452 453 40 Zeaxanthin 11 10 0 0 2 10.4 451.5 453 41 Decapreno-8-carotene 15 12 0 0 2 14.6 506’ 504 42 Dodecapreno-&carotene 19 14 0 0 2 18.8 53Sk 537 43 Tetradecapreno-&carotene 23 16 0 0 2 23.0 ... 559 ., . .. m ... 608 44 Compound with N = m Experimental data from P. Karrer and E. Jucker, “Carotenoids,” Elsevier Publ. Co., Inc., Houston, Texas, 1950, unless L. N. Ferguson, Chem. Rev., 43, 385 (1948). E. A. Braude and C. J. Timmons, J . Chem. Soc., otherwise indicated. 2007 (1950). B. C. L. Weedon and R. J. Woods, ibid., 2687 (1951). E. A. Braude, T. Bruun, B. C. L. Weedon and R. J. Woods, ibid., 1414 (1952). E. A. Braude, T. Bruun, B. C. L. Weedon and R. J. Woods, ibid., 1419 (1952). f K. Dimroth, Angew. Chem., 52, 545 (1939). f C. Bohlman, Chem. Ber., 85, 386 (1952). P. Rarrer, C. H. Eugster and M. Faust, Heh. Chim. Acta, 34, 823 (1951). a A. E . Gillam and M. S. El Ridi, Biochem. J . , 32, 820 (1938). j P. Karrer and C. H. Eugster, Heh. Chim. Acta, 34, 28 (1951). P. Karrer and C. H. Eugster, ibid., 34, 1805 (1951).
..
The difference in effect attributable to the chain length of the substituent is SO slight that i t can be ignored (see Table VI, 17-28). As Table IV shows, the position of the substituent also caused a slight difference which is always small compared with the effect of the chromophore; so that usually the rounded-off value for the ratio (0.1) is satisfactory for calculation purposes. If we define an index N , the homoconjugation index, as the value of the index n, corrected by sub-
.
stituent effects defined above, N will be in general non-integral and thus loses its meaning as the number of chromophores. Obviously, in the absence of auxochromic substituents, e,g,, in the a,w-diphenylpolyenes, N and are identical. The values for 1-24, Table V, calculated by equation 6, which contains N , agree well with the observed values. (A:&)*
= (36.98
- 39.10 X
0.92W) X 104mp2 (6)
37c,
K E N ZHIRAYAMA ~
Vol. 77
TABLE VI ABSORPTIONMAXIMUM OF COMPOUNDS ap 3 Compound
NO.
1 2 8 4
5 6 7 8 9 10
CHFCH-CH=CHZ M-CH=CH-CH=CH? Me-CH=CH-CH=CH-Me Et-CH=CHCH=CHCHzCOpH
2
0 1 2 2
m
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0
Obsd.
2.00 2.13 226 2.26
217" 223. 5b 22T 225"
PhCHLCH=CHCH=CHCIIZPh AcOCH~C€I=CHCH=CHCHZOAC EtOCH~CH=CHCH=CHCH~OEt Me?C=CHCH=CMe? CHZ=CMe-CH=CHl CH2=C-CH=CH?
I
12 13 14 15 I8 17
CH2CH?CH=CMet (myrcene) MeZC=CH-CMe=CHz CH2=CMe-CMe=CH2 CH2=CH-CH=CII-CHZOH CH2=CH-CH=CH-CHOH-Re CIIZ=CH-CH=CH-CMe?OH hleCH=CIICH=CHCIIOHhe
18
MeCH=CHCH=CHCHOH-
19 20 21
Me-CH=CH-CH=CH-CHOH-C=CI { Me-CH=CH-CH=CH-CEIOH-C= MeCH=CHCH-CHCMeOHCH==CHPli MeCH=CHCH=CHCMeOHC=CR R = Er
R =
23
0 0 1 1 0 0 0 0 0 0 0 0
Calcd.
(217) 222 228 225
220"
228
233' 228" 228= 231d
228 228 228 24 1
220"
231
224.5' 232d 225" 223' 223' 223.5' 2279
22 1 233 224 223 223 223 228.5
0 0
0
0
2.09 2.39 2. IS 2 15 2 15 2 15 2 28
1 0 0
2 28
228"
228.5
1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0
2 28 2 2s 2 28
2.730b 229b Qoqi
228.5 228.5 228.5
"y-2
1 0 0 1 0 0
2.28
22'7'
228.5
1 0 0 1 0 0
2.28
=
1 0 0 1 0 0
2.28
22gk
228.5
1 0 0 1 0 0
2.28
227k
228.5
1 0 0 1 0 0
2.28
230i
228. 5
1 0 0 1 0 0
2.28
22Qk
228.5
1 1 1 1 1 1 0
0 0 0 0 0 0 0
2.28 2.45 2.45 2.45 2.37 2.54 2.30
227' 236' 236' 237d 23jd
228.5 235 23 5 235 232 239 229
1 0 n 1 0 1 1 0 0 1 0 0 1 0 1 1 0
2.37 2.37 2.39
236.5" 23.73'
232 232 233
2 0 2 n 2 0 2 0
2.76 2.76 2.76 2.76
248" 245O 247O 246"
247 247 247 247
0
0 0 0 1 0 1 0 1
mu
0 0 0 0 0 0
1
1 1 2 0
xlns
hT
?O~CHzCH=CHCH=CHCH~co~H
11
22
>N 2
Subs;. and structure E E I A ex en
0 0
1 0 0 I
}?
1
0
0 0 0
-.a'
228.5
A
24
R
25
R
26
R=*
=
a a
27 28 29 30 31 32 33 31
Me-CH=CH-CH=CEI-CMeLOH Me2C=CH-CH=CH-CHLOH MezC=CH-CH=CH-CHOI-I-Me Me&=CH-CH=CH-ChleZOH Me-CH=CH-CMe=CH-CMaOH MezC=CH-C?rIe=CH-CMe?OH PhCHOHCH=CHCH=CHCHOHPh
X = H X = NMez X = OH
37, 38 ) 39 I 40 ; c > = c H c H = d A 41 I HO R 42 r(CH?)rCH=C-CH=CHz
X
1
X X X X
0 1 1 1 0 1 0
0 0 0 0 1 1 0
0 0 0 0 0 0 0
1
1 2 0 1 2 0 1 2 0 CHzCOzH 1 2 0
= H,R = H = H, R = Me = O H , R = CHzC02H
= OAc,R
1 1 1 1 1 1 2
1 1 1 1
23Gd
"10" 2386
1 0
1 0
0
1
2.26
2300
228
1 0
0
1
2.39
232'
233
43
r(CHz)rCH=C-CH=CHCHOMeMe
2 0
44
I-( CH2)&Me=C-CH=CHz
1 1 1
0 0
1
2.43
233"
234
45
r(CHZ)~CH=C-CM~=CH*
1 0 2 0 0
1
2.35
212'
23 1
CONJUGATED POLYENES AND ~POLYPHENYLS
Jan. 20, 1955
377
TABLE VI (Continued) Subst. and structure I A ex en
N
Obsd.
Calcd.
r(CHz)zCHMeCHzCH=CCMe=CH~
1 0 2 0 0 1
2.35
235c
231
,-( CHz)XH=C-CH=CHCHOHMe
1 0 1 1 0 1
2.41
235‘
234
1 0 1 0 1 1 2 0 2 0 0 2
2.33 2.52
232c 23@
230.5 238
No.
Compound
46 47
CHs=CCH=CH 48 49
I
E E’
I
CHzCHzCHCHMez CHz)rCH=C-C=CH( CHt)q
r(
Amax, m p
K. Dimroth, Angew. Chem., 52, 545 (1939). E. A. Braude, Ann. Refits. Prugr. Chem., 42, 105 (1946). e L. N. Ferguson, Chem. Revs.,43, 385 (1948). E . A. Braude and J. A. Coles, J . Chem. Soc., 1425 (1952). * R. B. Woodward, THIS JOURNAL, 64,72 (1942). f E. A. Braude and C. J. Timmons, J . Chem.Soc., 2007 (1950). 0 E. A. Braude and J. A. Coles, L. Crombie, S. H. Harper and D. Thompson, ibid., 2906 (1951). B. C. L. Weedon and R. J. Woods, ibid., 2085 (1951). ibid.. 2687 (1951). j 1. Attenburrow, A. F. B. Cameron. 1. H. ChaDman. R. M. Evans. B. A. Hems. A. B. A. Tansen and T. Walker, ibd., 1094 (lb52). T. Bruun, I. Heilbron, B.‘C. L. Weidon and R. J. Woods, ibid., 633 (1950). iE.A. Braude arid J. A. Coles, ibid., 2014 (1950).
I n the case of carotenoids, an a,@-epoxyalkylsubstituent (Ep) has a larger bathochromic effect NE^ = f0.2) than an alkyl substituent.6 Thus, NE^ = +0.2 was used in the calculation of N for compounds 25-27, Table V. It is known that a ring structure like ( r l ) exerts a
A
::lC 3
hypsochromic eff e ~ t .The ~ values for compounds 28, 29, 30, 41 and 42 Table V, were calculated with the assumption that N,, = -0.8; a ring with a hydroxyl group a t position 3 of r l has the same valueifor N as N,, (see Table V, 31-40). Our method is illustrated by the following calcuof tetradecapreno-@-carotene,which is lation of A,, still to be synthesized. The number of conjugated ethylene linkages n is 23, the number of alkyl substituents R is 16 and the number of conjugated rings r l is 2; then with N R = 0.1 and NrI= -0.8 N = 23 f (0.1 X 16) - (0.8 X 2) = 23.0 Theref ore = (36.98
-
39.10 X O.92Oz3)X lo4 mpz; A$:,.,
5.59 mfi
Substituted Butadienes.-Although equation 6 is quite satisfactory for compounds where N 2 3, the error becomes considerable when N < 3. The observed A2-N curve has a point of inflection a t N 3, while the curve plotted according to equation 6 has no such point. However, as the observed line shows only a slight curvature and is almost linear can also be calculated in the region 2 5 N < 3, A,, for this range from the homoconjugation index N according to equation 7. This expression was obfor tained from the straight line connecting the A,, N = 3 calculated by equation 6 and the observed A,, for N = 2; the observed line is assumed to be straight for 2 5 N < 3. (Amsl)) = (1.061 f 1.824 X N)X 104mfi2(25 N < 3 ) (7) Since in this case N is small, the effect of the substituents is relatively large; therefore, the values given in Table IV for the contribution of auxochromic substituents to N should be used rather of compounds 1-34, than 0.1. The values of A,,
+
( 5 ) L. F. Fieser, J .
Or#.Chem., 16, 930 (1950).
Table VI, calculated in this way show good agreement with those observed. Equation 7 is applicable to methanol, hexane, petroleum ether, ether, alcohol and light ligroin solutions, because the effect of these solvents is about the same in the range 2 S N < 3 (see Part 11). The good agreement between the observed and calculated values for compounds 4, 5 , 7, 8 and 1827, Table VI, shows that a chromophore or auxochrome, other than an alkyl and hydroxyl group, a t the a-position of an alkyl substituent has little bathochromic effect. The considerable discrepancy in compounds 6 and 34, Table VI, is probably due to overlapping of the absorption of the phenyl chromophore (ca. 220-270 mp) with that of the diene chromophore. The effect of the exocyclic ethylene group (3541, Table VI) is N, = +0.07. The observed absorption maxima of compounds 4 2 4 9 , Table VI, are generally larger than the calculated values unless the endocyclic ethylene (en) is taken into account; the effect of this linkage is Ne,
= +O.O4.
The above values NE^ = +O.lS, Nex = +0.07, and Ne, = +0.04) are used for compounds 2 6 N < 3, but for compounds N > 3 the rounded-off values (+0.2, +0.1 and 0, respectively) are sufficiently accurate. Calculation with these factors gives satisfactory results except for compound 45, Table VI; this large deviation may be due to an incorrect observed value, since good agreement was obtained for the analogous compounds (Table VI, 42, 44, 46,47 and 49). Steroid.-Equations 6 and 7 can be used without modification for conjugated unsaturated steroids ; see Table VII, 1-13. It has also been shown that the 1,z-dihydrobenzene ring (db) exerts a bathochromic effect,6 and the value of which is N d b = +0.83 (f0.8); the values calculated with this factor (Table VII, 1422,25-29 and 31) are satisfactory. The 1,2,5,6-tetrahydronaphthalene ring (tn), which is considered as two fused dihydrobenzene rings, should exert a bathochromic effect equivalent to more than one and less than two db rings; Ntn calculated from the observed values for the compounds30and32,TableVII, was f1.12 (+l.l). ( 6 ) L. F. Fieser and M. Fieser, “Natural Products Related t o Phenanthrene,” 3rd Ed., Reinhold Publishing Corp., New York, N. Y., 1949.
378
KEN26
Vol. 77
HIRAYAMA
TABLE VI1 ABSORPTION MAXIMUM OF STEROIDAL POLYENES Compound
NO.
1 2 3 4 6 6 7
8 9 10 11 12 13
7-Methylenecholesterol 3,5-Cholestadiene 5-Cholestene-3-one enol acetate Testosterone diacetate 4,6-Cholestadiene Ergosterol D 4,6-Chloestadien-3-01 Cholestadienol Ea Cholestadienol Bt acetate Ergosterol Ea 7,9(1l)-Cholestadien-3-01 acetate 6,8(14)-Cholestadien-3,9-diol 6,8( 14)-Cholestadien-3,9-diol 3acetate 2,4-Cholestadiene Ergostatriene
n
E
E'
2 2 2 2 2 2 2 2 2 2 2 2
1 2 2 2 2 2 1 2 2 2 2 2
1
0
0 0 0
1 0 0 0 0 0 I
Subst. and structure A ex I
1 1 1 1 1
2 1 2 2 2 2
0 0
0 0
dh
tn
.V
0bsd.a
Ca1cd.h
2
1
0
1 1
2 2 2 2 2 2 2 2 2 2 2
fl
0 0
0
ii
0
(I ).I 0 0
2.57 2.50 2.50 2.50 2.50 2.76 "52 2.61; 2.66 2.66 2.66
236 240 240 240 238 242 238 248 246 242 245 248
240 237 237 237 237 247 238 243 243 243 243 248
I
0
1
0 1 0
1 1 2 2 2 2 2
0 0 0 1
~ E Z mw ,
en
0
0 0 0
i)
0 0 0
0
n
0 0
o
2.80
2 0 245 248 2 2 1 0 1 2 0 2.80 0 1 0 3.31 (1 1 275 270 2 2 1 0 0 1 0 3.55 2 0 0 2 280 281 2 2 0 1 0 3.55 280 281 2 0 0 2 5,7-Androstadien-3,17-diol 2 2 0 1 0 3.55 281 281 2 0 0 2 7-Dehydrocholesterol 2 2 0 1 0 3.55 280 281 2 2 2 0 0 2 Ergosterol o 3.55 280 281 2 2 2 o o 2 n I Lumisterol Pyrocalciferol 2 2 2 0 0 2 0 1 0 3.55 280 281 0 3.37 275 273 1 1 1 1 0 0 6,8-Cholestadien-3-01 2 2 6,8-Coprostadien-3-01 2 2 1 1 0 0 1 1 0 337 270 273 Vitamin DZ 3 1 1 2 0 3 0 0 0 3.69 265 287 Tachysterol2 3 2 1 2 0 0 2 0 0 3.69 280 28i 4,6,22-Ergostatrien-3-oneenolacetate3 2 0 1 0 1 1 1 0 4.27 304 310 3,5,7,22-Ergostatetraene 3 2 1 1 0 2 1 1 0 4.51 316 318 5,7,22-Ergostatrien-3-oneenolacetate 3 2 1 1 0 2 1 1 0 4.51 316 318 5,7,9(ll)-Cholestatrien-3-01 3 2 1 2 0 3 1 1 0 4.67 320 324 Dehydroergosterol 3 2 I 2 0 3 1 1 0 4.67 320 324 6,8,11-Cholestatrien-3-01 3 2 0 2 0 0 0 0 1 4.56 325 320 5,7,9( 11),22-Ergostatetraen-3-one enol acetate 4 2 0 3 0 3 2 1 0 5.6i 356 355 32 4,6,8,1l-Cholestatetraen-3-01 4 2 0 3 0 1 2 0 1 5.80 355 359 a Experimental data from L. F. Fieser and M. Fieser, "Satural Products Related to Phenanthrene," 3rd. Ed., Reinhold Publishing Corp., New York, 1v. Y., 1949; K. Dimroth, Angew,. Chew?.,5 2 , 545 (1939); E. 4 .Braude, Ann. Repts. Progr. = 1.061 f 1.824A' Chem., 42, 105 (1946). * Calculated by (Xmax)z = 36.98 - 39.10 X 0.920"dp2when S 2 3, or by dp2 when 3 > N 2 2. 14 15 16 17 18 19 20 21 22 23 24 25 26 27 78 29 30 31
Since -Vis usually a small number in the case of unsaturated steroids, the values for the substituent effect should not be rounded-off. The absorption maxima calculated by this method (Table VII) show good agreement (except for compound 23) especially in the region 2 N < 3 . 5 ; deviation from the ObserVed values 1s relatively large when N is greater than 3.6. The Values for compounds (Table VII, 3, 4, 27 and 31) talculated with Lvacetoxy = 0 agree well with the observed values. Acknowledgment.-The author expresses his thanks to Drs. R'I. Kotake, T . Sakan, R. Tsuchida, M. Kobayashi, H. Kuroya and Y . Saito for their interest and advice and to Dr. N . Fukuwara for his help in preparing the manuscript.
.
