Note: Descriptions are shown in the official language in which they were submitted.
Description of the prior art
It is known to manufacture highly concentrated liquid commerical forms
of dyestuffs by dissolving the dyestuff powders or pastes, in
suitable aqueous, organic or organic-aqueous media, whereby highly
concentrated liquid dyestuff preparations are produced, which, as
regards handling and use,offer advanage6 in several respects over the
dry dyestuff preparations.
Dry dye powders are troublesome to manufacture and use in the mills
for dyeing paper. Drying, grinding, dust-treatment, and standardization
operat-ions are required in the manufacture of the dye powders. In
addition to dusting problems, the cold water beater dyeing strength of
the dye powders on paper prepared from the dyed pulp is generally low.
Moreover, the slow rate at which dye powders dissolve in cold water
is a particular disadvantage, especially during winter months when
the temperature of water used in paper dyeing operations may
approach the freezing point. This lack of solubility also makes it
difficult to use such dyes in continuous systems where pumping and
metering of uniform dye solutions or suspensions is necessary for .-?
efficien~ operation.
The manufacture of concentrated liquid dyestuff preparations is,
however, frequently associated with difficulties, since the dyestuffs
used as starting products have in most cases been obtained by salting-
out and therefore contain a considerable proportion of salts, which
at times are disadvantageous when manufacturing the liquid
preparations, and the presence of which can have an adverse
influence on the stability of such solutions.
The prior art, as exemplified by United States Patent 3,621,008 has
manufactured soluble bis-urea-dyestuffs by phosgenating in aqueous
solution the Na , K , Li or NH4 salt of a sulfo- or carboxyaryl-
-- 2 --
azoaryl amine where at least 50 atom percent of the cation is Li orNH4 . By the practice of the instant invention, it is possible to
obtain not only dyestuffs thatare more soluble but also form stable
solutions having a higher concentration of dyestuff than can be
obtained by the prior art practice.
The use of a lithium base as claimed in order to maintain the desired
pH value during phosgenation is very important and much superior to
the use of an alkanolamine for pH-control throughout the
phosgenation reaction because a rather large precipitate of alkanol-
a~monium chloride forms in the latter case, which then requires
-excessive dilution to dissolve the precipitate, or a major
filtration operation to obtain concentrated solution.
One aspect of the present invention provides a stable concentrated
dyestuff solution, containing, on a weight basis,
a) about 10 to about 50 % of a dyestuff of the formula
E-A-N=N-B-NH-C-NH-B'-N=N-A'-E'
where E is S03H;
E' is S03H or COOH; and
A, A', B and B' are each independently a naphthylene or phenyl-
ene group, unsubstituted except by E and E' or further substituted
by one or two groups, one of which is selected from the group con-
sisting of hydroxy, nitro, cyano, trifluoromethyl, carboxy and
S03N, where M is K, Na, Li or H and/or one or two is selected from
the group consisting of lower alkyl, lower alkoxy, hydroxylower-
alkyl, hydroxyloweralkoxy and halogen,
(b) about 20 to about 90 % water,
(c) about 0.1 to about 1.0 % Li
~d) less than about 1.5 % Na or K and
~e) about 3 to about 15 % of an alkanolamine of the formula
.~ ~
'
x-~-z
where X, Y and Z are each independently loweralkyl substituted with
at least one hydroxy group, loweralkoxy-loweralkyl substituted with
at least one hydroxy group, or Cl-C4 alkyl, provided that no more
than two of X, Y and Z are Cl-C4 alkyl.
Another aspect of the invention provides a process of making a
stable concentrated dyestuff solution, comprising the step of re-
acting phosgene with an aqueous solution of an alkanolamine salt of
an aminoazo compound of the formula E-A-N-N-B-NH2, alone or mixed
with no more than 50 mole ~ of an aminoazo compound of the formula
E'-A'-N=N-B'-NH2, at a temperature of 35C to 60C, while maintain-
ing the pH of the reaction solution at a value in the range of 5.0
to 8.5 with a lithium base alone or in combination with no more .;
than 35 % of triethanolamine, N-methyldiethanolamine or N,N-dimethyl-
ethanolamine; wherein
E is S03H;
; E' is S03H or COOH; and
: ~ A, A', B and B' are each independently a naphthylene or
phenylene group, unsubstituted except by E and E' or further sub-
stituted by one or two groups, one of which is selected from the
group consisting of hydroxy, nitro, cyano, trifluoromethyl, carboxy
~ ; and S03M, where M is K, Na,~Li or H and/or one or two is selectedr ` from the group consisting of lower alkyl, lower alkoxy, hydroxy-
loweralkyl, hydroxyloweralkoxy and halogen, and wherein the
alkanolamine is of the formula
'. Y
., X-~-Z
where X, Y and Z are each independently loweralkyl substituted with
at least one hydroxy group~ loweralkoxy-loweralkyl substituted with
at least one hydroxy group, or Cl-C4alkyl, provided that no more than
:` ~
:
-- 4 --
two of X, Y and Z are Cl-C4 alkyl-
The above-described phosgenation of the selected aminoazo compounds
produces, in solution, disazo urea dyes of the formula
O
E-A-N=N-B-NH-C-NH-B'-N-N-A'-E'
wherein A, A', B, B', E and E' have the meanings set out above. The
phosgenation reaction can be carried out on a single aminoazo sulfonic
acid compound, or a mixture of am~inoazo sulfonic acid compounds, or
a mixture of one or more aminoazo sulfonic acid compounds with one or
-more aminoazo carboxylic acid compounds, provided in the latter case
that at least 50 mole percent of the mixture is an aminoazo sulfonic
acid compound or mixture of aminoazo sulfonic acid compounds. One
skilled in the art will realize that the above structural
representation of the disazo urea dyes is actually descriptive of the
- average result of the phosgenation reaction. That is, when the aminoazo
compound starting materials are used as a mixture (where A and A' and/
or B and B' are not identical or where a mixture of sulfonic acid and
carboxylic acid dyes i8 chosen), the final product, if produced by
~ random combination, would contain some of each kind of symmetrical
i~ disazourea dye as well as the unsymmetrical structure. Therefore, in
addition to depicting one of the final product species present after
--~ phosgenation, the above structure also represents the average
i composition or the summed contributions of each of the possible
- species, where mixed starting materials are used.
~
It will be appreciated from the above discussion that A and A' can be
the same or different, and B and B' can be the same or different. In
the discussion below of preferred A and B moieties, occurring in the
starting material dyes, it should be appreciated that preferences for
A and B in the starting materials also apply to A' and B' in the
final product.
: .
: ~i
.
- 5
It is preferred that B is phenylene, either unsubstituted or
substituted with one or two substituents selected from the group
consisting of methyl, methoxy and chlorine; and that A i9 phenylene
or naphthylene, particularly where the substituted A is selected from
the group consisting of sulfophenyl, carboxyphenyl, mono- or di-
sulfonaphthyl and carboxynaphthyl, either not further substituted or
substituted with one or two substituents selected from the group
consisting of methyl, methoxy, ethoxy, hydroxyethyl, hydroxyethoxy
and chlorine and/or one substituent selected from the group
consisting of hydroxy and S03M. Especially preferred substituted A
radicals are the following: .
HO
N035 ~ _ ~_ ~
The aminoazo compounds can be prepared by well-known prior art methods,for example, by diazotizing an appropriate sulfo- and/or carboxyaryl
amine, and then coupling the diazQnium compound to a second
appropriate arylamine, of the benzene or naphthalene series such as
an aniline, toluidine, or cresidine as such or in the form of an
N-methanesulfonic acid, in which case the coupling is followed by a
saponification step to obtain the aminoazo compound.
The aminoazo compound may be isolated in its free acid form after
preparation. If the aminoazo compound is available as a salt, it can
be converted to the free acid form by acidification in water with a
strong acid such as hydrochloric acid or sulfuric acid. The
precipitated acid form is filtered off and washed, as needed, to
reduce further the amount of undesirable cations, e.g. with 0.1 N
hydrochloric acid containing O to 5 % sodium chloride.
~L
-- 6 --
The production of the concentrated dyestuff solutions is for example
initiated by dissolving the aforedescribed aqueous acid aminoazo
compound filter cake in a sufficient amount of a liquid alkanolamine,
or in a concentrated aqueous solution of such, so as to obtain a
neutral or slightly alkaline solution at 20 to 50 C, which thencontains the alkanolammonium salt of the aminoazo compound.
As tertiary amines which can be used to neutralize the acid amino-azo
compounds according to the invention, there are the amines of the
formula
Y
X-N-Z
whereby at least one of X, Y and Z is
hydroxyloweralkyl or hydroxyloweralkoxyloweralkyl, optionally
substituted with additional hydroxy groups, and containing from two to
~: ~ix carbon atoms, as for example the following radicals:
"
CH2CH20H, CH2CH2CH20H, CH2CROHCH3, CH2CHOHCH20H, CH2(CHOH)4CH20H,
CH2-C(CH20H)3, CH2CHOHCH20CH2CH20H, CH2CH20CH2CH20H~
CH2CH20CH2CH20CH2CH20H;
and whereby up to two of X, Y and Z can also be (Cl 4~a}kyl,
~ especially methyl.
-
Examples of such amines are:
CH3-N(CH2CHOHCH3)2, CH3-N(CH2CHOHCH20H)2
3-N(CH2CH20H)-CH2(CHOH~4CH20H' CH3-N(CH2CH20CH2CH2H)2'
CH3-N (CH2CH20H) -CH2CH20CH2CH20CH2CH20H;
(CH3)2N-CH2C~IOHCH20H~ (CH3)2N-CH2C(CH20H)3, (CH3)2N-CH2(CHOH)4CH20H~
(CH3)2N-CH2CHOHCH20CH2CH20H, (CH3)2N-CH2CH20CH2CH20H,
3 2 3 2 H20H, (c2H5)2N-cH2cH2ocH2cH2ocH2cH2oH;
~r
-- 7 --
(HOCH CH2)2N-CH2CH2CH2H' (HCH2cH2)2N CH2 2 2 2
H0CH2CH2-N(CH2CHOHCH3)2, H0CH2CH2-N(CH2CH20CH2CH20H)2.
N(CH2CH2CH20H)3, NtCH2CH20CH2CH20H)3. N(CH2CHOHCH20H)3-
Preferred tertiary alkanolamines used to neutralize the acid aminoazo
compounds before phosgenation are:
Triethanolamine, N(CH2CH20H)3; 2-N,N-Dimethylaminoethanol, .-
(CH3)2N-CH2CH20H; and N-methyl-diethanolamine, CH3-N(CH2CH20H)2.
The phosgenation reaction of this invention is carried out by
introducing phosgene into an aqueous alkanolammonium salt solution of
an appropriate aminoazo compound or a mixture of same, for example,
by bubbling phosgene gas into the reaction vessel beneath the
surface of the aqueous solution.
As soon as phosgene is added, the pH decreases due to the liberation
of hydrogen chloride. During the reaction, the pH of the reaction
mixture is maintained at 5.0 to 8.5 with a lithium base such as
lithium bicarbonate, lithium carbonate, or preferably lithium
hydroxide. The preferred pH is 6.5 - 7.8. At a pH less than 4.0 the
reaction rate is undesirably slow and it becomes more difficult to
maintain a solution or fine suspension of reactants and product. At
a pH above 7.8 the competing hydrolysis of phosgene is favored, thus
resulting in excessive 1088 of this reactant. The preferred base is
lithium hydroxide. Lithium carbonate is re difficult to add since
its low water solubility precludes use of a concentrated aqueous
solution. Lithium bicarbonate is less basic and, therefore, is more
costly to employ. Up to 35 % of the chosen lithium base can
optionally be replaced with the equivalent of a suitable tertiary
alkanolamine, particularly triethanolamine, N-methyl-diethanolamine,
or 2-N,N-dimethylaminoethanol, in order to maintain the desired
pH value during the introduction of phosgene.
-- 8 --
The reaction temperature should be such that preferably a solution or
a~ least a very fluid finely divided slurry is maintained throughout
the reaction. The temperature selected will depend, to a certain
extent, on the volume of water present, and the latter will depend,
to a certain extent, on the dye concentration desired in the reaction
product since the present invention makes possible the direct use of
the liquid reaction product. The preferred temperature is 35-60C
since at this temperature an excellent combination of reaction rate
and solubility can be achieved. Moreover, at this temperature the
reaction can be carried out at atmospheric pressure, thus simplifying
equipment requirements.
Theoretically, two moles of appropriate aminoazo compound are
required for each mole of phosgene. Since some hydrolysis of phosgene
is unavoidable, an excess of the stoichiometric amount of this
reactant must be employed. Since it is difficult to predict the
amount of phosgene which will be lost via hydrolysis, it is preferred
to determine the progress of the reaction by removing, from time to
time, a sample of the re~ction mixture and either acidifying it to
observe the color change, which is tifferent with the azoamine and
the phosgenated product, or eventually determining the disappearance,
or near-disappearance, of original aminoazo compound(s) by a
chromatographic procedure.
When the phosgenation reaction is completed, the reaction mixture is
cooled and the pH is adjusted, usually to 7.0 - 8Ø The liquid
reaction product then may be sampled for standardization, diluted
with water or concentrated, if necessary, to achieve the desired dye
strength, and packaged for direct sale and use. The process of the
present invention does not preclude isolation of the dye product
and the use of the resultant dye powder in a manner analogous to
similar prior art dyes. All of the advantages of the present invention
relative to improved preparation,higher solubility of the dyes and
Q3
g
the like, accrue to dye powders prepared by means of this invention.
However, since the present process provides a concentrated liquid
product, economics often favors the use of the liquid products
directly. By the process of the present invention stable aqueous ;
solutions containing about 10 to about 50 weight percent active dye
ingredient can be prepared. Moreover, the process of this present
invention permits the introduction of additives, for example urea,
organic solvents, or dispersing agents directly to the phosgenation
reaction mixture.
. .
Auxiliary solubilizing agents, which can optionally be added include:
the amides of inorganic or organic acids, preferably carboxylic acid
amides, e.g. those of monobasic or dibasic carboxylic acids, such as
the amides of carboxylic acids containing up to 8 carbon atoms, e.g.
2 to 4 carbon atoms, such as acetamide, propionic acid amide, as well
as malonic acid diamide. Urea and urea derivatives are partic-
ularly suitable; examples besides urea itself are substituted or
unsubstituted alkylurea compounds such as methyl and ethyl urea,
N,N'-dimethylurea and dihydroxyloweralkyl ureas. Further guanidine
and its derivatives such as methyl guanidine are suitable. Also
formamides such as alkyl formamide, e.g. methyl- and dimethyl-
formamide can be used as well as sulphonic acid amides or diamides.
There can also be added glycols and glycol ethers such as
Cellosolve*, Carbitol*, etc.
Further auxiliary agents are, for example, antifoaming agents.
The new process is particularly valuable for the manufacture of
disazo dyestuffs of the formula
o
E-A-N=N-B-NH-C-NH-B'-N~N-A'-E'
* Trademarks
-- 10 --
wherein -A-E- and -A'-E' represent radicals of disazo components of
the sulphobenzene or the mono- or di-sulphonaphthalene series and
B and B' represent radicals of coupling components of the benzene
series (see, for instance, Examples 3 and 4); and wherein A and A'
and/or B and B' can also be identical as,for instance, described in
Example 1.
Likewise, the new process is particularly valuable for the
manufacture of disazo dyestuffs of the same formula wherein E-A-
represents a radical of a diazo component of the sulphobenzene or the
mono- or di-sulphonaphthalene series, E'-A'- represents a radical of
the carboxybenzene or carboxynaphthalene series and B and B' are as
above, as for instance, described in Example 2.
The highly concentrated solutions of tertiary ammonium salts of direct
dyes obtained according to the process of this invention contain on
a weight basis,
a) 10 to 50 %, especially 18 to 40 %, of the tertiary alkanolammonium
salt of a disazo urea dyestuff, as described above,
b) about 20 to about 90 % of water, especially about 50 to about 80 %,
c) about 1 % or less of Li but especially about 0.5 - 0.9 %,
d) under about 1.5 % of Na , especially about 0.05 - 1.0 %,
e) about 3 - 15 % tertiary alkanolammonium salt, calculated as free
amine, especially about 3.5 - 10 %, and
f) 0 to about 40 % of an auxiliary agent or a combination of auxiliary
agents, especially a solubility-enhancing agent.
~1 .
The highly concentrated solutions prove stable even on prolonged
standing and the dyestuff neither crystallizes out nor decomposes.
They are miscible in any ratio with water and/or water miscible
organic solvents. They are particularly suitable for the manufacture
of solutions for dyeing paper pulp and for dyeing textile fibers,
but can also be used for other purposes.
The dyes of the present invention may be used directly in the form of
a solution as prepared, or as dry powders, to dye cellulosic
materials, especially paper, in the usual paper mill equipment. The
following description represents a typical dyeing operation. Normally
0.1 to 3.0 parts of the dye liquid are added to an aqueous slurry of
100 parts (dry basis) of bleached sulfite pulp in 5,000 parts of
water at ambient temperature (2-38C); 0.5 to 3 parts of rosin
size (sodium rosinate) and 1 to 4 parts of aluminum sulfate
octadecahydrate then added. The mixture is thoroughly agitated for
10 to 20 minutes and water is added as needed to give a total of
20,000 to 25,000 parts. Paper sheet is then made up in the usual
manner. The dye liquids of the invention can also be used for
continuous coloring of paper by constant metering of the dye
liquid into the pulp slurry, or in liquid formulations for the
dyeing and printing of paper and cardboard by surface application.
Example 1: 84.2 parts of 2-(4'-amino-2'-tolylazo)-naphthalene-6,8-
disulfonic-acid obtained by combining diazotized 2-amino-
naphthalene-6,8-disulfanic acid with m-toluidine in a known manner,
e.g. in aqueous medium at 10 to 25C and a pH value adjusted to 3,
and isolating the precipitated coupling product at a pH near 1
through filtration followed by washing with sufficient 0.1 normal
hydrochloric acid to replace most of the salt-containing mother
liquid from the filter cake, as filter cake containing about 50 %
water, are dissolved ir. 36 parts of triethanolamine and 24 parts of
: ` :
- 12 -
water at pH 7 to 8 and 35C. Phosgene is introduced under
agitation and the temperature is permitted to rise over 40C. The
dropping pH value is held at 6.7 to 7.5 by the gradual addition of
4.6 normal aqueous lithium hydroxide solution until the aminoazo
compound is largely used up. (It required about 25 parts of
phosgene and 11 to 12 parts of LiOH in a period of about 2 hours to
obtain about 360 parts of liquid).
The thin suspension is diluted with 180 parts of hot water and
clarified at 70C in the presence of 3 parts of Dicalite* to remove
a small amount of fine insoluble material. About 540 parts of
solution are obtained which is stable in customary storage and
resistant to chilling induced precipitation. It contains 27 % solids
, .,
including about 22 Z dyestuff alkanolamine salt.
It dyes paper fibers from cold or hot water in reddish yellow shades.
When the dilution of the thin suspension is done with 54 parts of
Cellosolve (or a mixture of Cellosolve and Carbitol, totaling 54
parts) in place of the 180 parts of water and the remainder of the
procedure is carried out as before, 414 parts of solution is obtained
(containing about 35 ~ solids including 29 ~ dyestuff alkanolamine
salt).
When the 36 parts of triethanolamine above are replaced by 27 parts of
N-methyl-diethanolamine-2 or 20 parts of 2-N,N-dimethylaminoethanol,
respectively, stable solutions are obtained after a final dilution
with water to get 540 parts, as before. If ca. 100 parts of water are
added in the beginning, a-solution is maintained throughout the
reaction.
* Trademark
:: :
q ?3
- 13 -
When urea is added to the above aqueous solutions in the amount of 4 to12 % by weight, their stability is prolonged. Additions of 6 - 12 %
triethylene glycol or 4 - 8 % "Ethomeen* C/25" (by Armour) have a
similar effect.
Example 2: 61,4 parts of 4-amino-3-methoxy-azobenzene-3'-sulfonic acidand 51.4 parts of 4-hydroxy-4'-aminoazobenzene-3-carboxylic acid,
as filter cakes containing 60 to 70 % water are dissolved at pH 7 to
8 in 79 parts of triethanolamine, 75 parts of Carbitol is added and
a total of ca. 45 parts of phosgene is introduced under agitation at
35 to 45C while a pH range of 6.8 to 7.8 is maintained by the
simultaneous addition of 4.6 normal aqueous lithium hydroxide
solution (containing a total of about 40 parts of LiOH-H20) until the
aminoazo compounts are largely used up. 75 parts of Carbitol are
added during the phosgenation and the final suspension is dissolved
completely with 140 parts of Cellosolve. 960 parts of stable
solution are obtained (containing about 25 % solids and including
18 % dyestuff alkanolamine salt) which dyes paper, cotton and nylon
in fast greenish yellow shades.
The aminoazo compounds used were obtained by processing the weakly
alkaline filter cakes regularly available after e.g. combining
diazotized metanilic acid and sodium o-anisidine-~-methanesulfonate
unter known aqueous conditions, followed by hot alkaline
saponification, salting and cold filtration on the one hand; and,
on the other, combining diazotized p-nitroaniline and salicylic acid
under known aqueous contitions, followed by retuction of the nitro
group with sodium sulfide, salting, filtration and brine washing;
as follows:
Dissolve the sodium 4-amino-3-methoxy-azobenzene-3'-sulfonate in
water (ca. 1:10) at 25 to 30C, acidify with conc. hydrochloric acid
*Trademark
.~, . ., , ~ ,. ,, -.
- 14 -
to about pH 1, filter the precipitated free acid form and wash with
N/10 hydrochloric acid to replace most of the salt-containing mother
liquor from the filter cake. Dissolve the sodium 4-hydroxy-4'-amino-
benzene-3-carboxylate in water (ca. 1:20) at 60C, acidify with conc.
hydrochloric acid to about pH 1, filter the precipitated free acid
form at 40C and wash liberally with N/10 hydrochloric acid.
Example 3: 61.4 parts of 4-amino-3~E~hoxy-azobenzene-3'-sulfonic acid,
obtained as described in Example 2, and 84.2 parts of 2-(4'-amino-2'-
tolylazo)-naphthalene-4,'8-disulfonic acid, obtained in a manner
similar to that described for the starting material of Example 1, are
dissolved as filter cakes at pH 7 to 8 in 76 parts of triethanolamine.
Phosgene is introduced under agitation'at 35 - 60C, while a pH
range of 6.8 to 7.8 is maintained by the simultaneous addition of
4.6 normal aqueous lithium hydroxide solution (containing a total of
about 40 parts of LiOH-H2o) until the amino compounds are largely used
up. About 690 parts of solution are obtained. When 11.1 parts of
urea are dissolved in each 100 parts of said solution, it remains
stable between 0 and 50C in customary storage and contains about
28 ~ dyestuff alkanolamine salt.
When the phosgenated solution, before dilution with urea, is spray
dried, a very water soluble powder is obtained.
When the 84.2 parts of 2-(4'-amino-2'-tolylazo)-naphthalene-4,8-
disulfonic acid in the above example are doubled while no 4-amino-3-
methoxy-azobenzene-3'-sulfonic acid is used as starting material,
and the final dilution is carried out as above or proportionately as
outlined in Example 1, the corresponding dyestuff solutions are
obtained.
The solutions described in this example dye paper by the customar
procedures from hot or cold dye baths in fast and strong yellow
shades.
... .
- 15 -
Example 4: 21 parts of 2-(4'-amino-2'-tolylazo)-naphthalene-6,8-
disulfonic acid (obtained as described in Example 1), 20.4 parts of
2-(4'-aminophenylazo)-naphthalene-6,8-disulfonic acid and 30.7 parts
of 4-amino-3-methoxy-azobenzene-3'-sulfonic acid (both obtained as
described for the latter in Example 2), are dissolved, as filter
cakes, in 36 parts of triethanolamino at a pH 7 to 8 and 35C.
Phosgene and lithium hydroxide are introduced as described in Example 1and Cellosolve and Carbitol - in the total amount of 25 to 35 parts
per final weight of ~he dyestuff solution, and at least five parts
of Cellosolve and 10 parts of Carbitol - are added gradually or in one
or several portions so as to prevent serious thickening or maintain
a solution until the amino compounds are largely used up. (This
required not more than 30 parts of phosgene and 13 parts of LiOH. It
took 2 to 2 L/2 hours.)
450 to 500 parts of a stable solution are obtained, which contains
about 21 - 23 % alkanolamine dyestuff salt and dyes paper and cotton
in strong yellow shades.
By following the procedures exemplified above one or more of the
following compounds can be reacted to yield stable concentrated
solutions of dyestuffs substantive for cellulose.
OCH3
~ ~--N=N--~ ~--NH2
.=. =--
S~3H OCH3
HO S--~ ~--N=N--~ ~--NH
C~
~ $1~ 3
- 16 -
OCH3
_ _ --
N=N~ --NH2
~ S~3H CH3
:,
:, ._. ._.
.=. ~.=./ 2
SO3H
HOOC~
HO--~ ~--N3N--~ ~--NH2
. C~ .
HOOC~ ~OCH3
Cl--~ ~--N-N--~ ~--NH2
.,.. .~.
HOOC~
HO--~ ~--N-N--~ ~--NH2
HOOC~ ~OH
-N-N--~ ~--NH2
OCH3
SO3H 3~
~ t-N-N--~ ~--NH2
HO3S
SO3H CH3~
T b t N N--~ ~--NH2
~./-\.~- =-
SO3H
, .: ::
:. : ~ ,
- 17 -
: SO3H
t~ il t-N=N--\ ~ NH2
HO S i~-/ \-~
SO3H ~OCH3
-N=N- -~ ~ NH2
i HO3S ~
SO3H ~OCH3
i~ t -N'N- -~ ~--NH2
./ \.~
SO3H
3 \ ~ t-N-N--~ ~--NH2
~./\.,~ /
SO3H CH3
~ ~--SO H
HO3S--~ ~--N=N--~ ~--NH2
SO3H ~OCH3
t~ t-N=N--\ ~ N 2
SO;H 3
. ~ ~
-
- ~ ,:
:,
- 18 -
\, / ._.
/ \--N=H~ --NH
HO3S/ O/CH3
OCH3
i il ~i-N=N--~ ~--NH
HO S/ ~ O/CH3
~SO3H
\ /
/ \--N-N--~ ~--NH
O~H3
OC2H5 OCH3
~ ~ N=N--~ ~--NH2
- S~;H
- ~Cl HO
HO3S--~ ~.-N-N-~ /NH2
SO3H
- :. :
~L$~ 3
-- 19 --
HO
\ ~--N=N- t~ T'N 2
3 SO;H
OH
Ho-C2H40--~ ~.-N-N-t il t
S03E 2
HO
._ . . .
-- S03H 2
103H ~OCH3
t~ t-N=N;--~ NH
t~
3 S03H
S03H
t iI t N-N--~ ~--NH2
~03E
t-NSN--~ ~--NH2
:. /-~ /-\ ,~- / \
3 ._.
S/O H
.. :~ : :
~`'',',' ~ ~
`
, . . .
-- 20 --
H0
~!, ,.~
S03H 2
~./-\.,~-
. ~
::.: .. :,
:: :. ,: . .-:
- : . .
: :, .: , : , : :
:, : : - . :::::: :
: :- :'::: .': : : . -
::, ' :` :
. .
