CA1266484A - Tert-octylhydrazine, its salts and derivatives - Google Patents

Abstract

Abstract of the Disclosure Mixtures of di-tert-octyldiazene (where tert-octyl refers to 1, 1, 3, 3-tetramethylbutyl) and tert-octyl secondary or primary alkyl diazenes are prepared by reacting mixtures of tert-octylamine and a primary or secondary alkyl primary amine with sulfuryl chloride and oxidizing the resultant mixture of sulfamides with basic bleach. Then, the mixture of diazenes is heated in a chlorinated solvent and the di-tert-octyldiazene decomposes and the unsymmetrical tert-octyldiazene rearranges to a tert-octylhydrazone. The tert-octylhydrazone is extracted out of the solvent with dilute acid, the acid solution extract is heated to 40-50°C, and the ketone that forms is stripped off under reduced pressure. The acid solution is neutralized to form tert-octylhydrazine. The tert-octylhydrazine is an intermediate that can be reacted with various compounds, e.g., ketones, aldehydes, acids, acid chlorides, isocyanates, chloroformates and sulfonyl chlorides to form different t-octylhydrazine derivatives.

Description

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Tert-Octylhydrazine, It s Salts and Derivatives . (IR 2744) . .
Back~ound of the Inven~ion Field of the Invention 5 This invention relates to ~ert-octylhydrazine (i.e.
~1,1,3,3-tetramethylbutylhydrazine), tert-octylhydrazine salts and deri~atives of t-r~-occylhydrazine and, more '~1i`' particularly, to che preparation of novel .
tert-octylhydrazones ! their hydrolysis to ~ert-octylhydrazine salts, the neutralization of the salts ~o the free base tert-octylhydrazine and the conversion of the free base to other derivatives such as acid sal~s, hydrazones, hydrazides, semicarbazides, carbazates or sulfonylhydrazides.

Prior Art lS To the best of our knowledge tert-octylhydrazine (i.e.
1l1,3,3-tetramèthylbutylhydra7ine) has never been successfully synthesized pr1or to this inveniton. Likewise, none of its salts or derivatives have been reported.
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/-.. , Our U.S. Patent 4,604,455 entitled "Azoalkan~ Mixtures Containing Unsymmetrical Azoalkanes, Their Method of Preparation", discloses for the first time the prepar~tion Oe unsymme~r~cal eer~-ocEyL.sec-al~yldiaZeneS.
S Ur~symmetrical eer~oc~yl cert-alkyldiazenes which are known bu~ are incapable of isomerizing to ter~-oceyLhydrazones (J. W. Timberlake, M. L. Hodges and .~. W.:Garner, Te~rahedron Lett. p.3843, 197.3; J. W. Timberlake, J. Alender, ~

Garner, M. L. Hodges, C. Qz~e~al, S. Szilagyi, J. Org. Chem.

10 46, p.2082, 19~31). `
I~ is known in the literature ~ha~ sec-alkylazos can isomerize co hydrazones upon heating. Co~Ley and Gipian r~por~ted that secondary aralkyl azo compounds isomerize co hydrazones in chlorinated solvents (R. Corley and M. Givian, 15 J. Org. Chem. 37, p. 2910, 1972).

Statement of the Inven~ion This invention relates ~o tert-octylhydrazine (I), a CH3-c-cH2-l-NH NH2 266~84 ~ .
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C' novel mono-subs~ituted s~erically hindered tert-alkylhydrazine.
Due to the bulky tert-octyl substitutent, it was not possible -to synthesize this compound by the conventional techni~ues and consequently it has not been prepared prior to this .5 invention. --This invention, also, relates to the novel acid salts oftert-octylhydrazine of the general formula 11.
C~3 CH3 .. _ CH3 CX3 ~ n '.: r~
where n = 1 or 2; when n is 1, A is selected from HCl, HBr, H2SO4~ H3PO4~ -O ; O O
Il 11 11 RCOH or HOC-COH where R is selected from H, CH3, C2HS, 20~ C3H7, i-C3H7, and C6H5; and when n is 2, A is selected from one of the following O O O O
Il 11 11 11 H2SO4, HOC-COH or HOCCH2CH2COH.

This invention also is directed to the novel tert-octylhydrazones of the general formula T IIo _ CH3-C-CH2-C-NH-N=C-R2 .

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- where Rl and R2 are independently selected from alkyl or i:
;~ ..
substituted alkyl of 1-12 carbons, preferably 1-6 carbons, . :.~
r~
cycloaliphatic of 3-12 carbons, preferably 3-7 carbons, or to~ether can form an alkylene diradical of 3-11 carbons, preferably.4-7 carbons and Rl can also be hydrogen and R2 can also be phenyl or substituted phenyl of 6-14 carbons, preferably 6-10 carbons.
The invention also comprehends the novel derivatives of tert-octylhydrazine of general structure IV and V
. IH3 CIH3 3-c-cH2-c-NH-NH-y `~ CH3 CH3 ~V
_ ~ .
.~ IC~3 IH3 CH3 -C-CH2-C-~H-~IH Z ~:
_ H3 CH3 ' ~ 2 V

where Y is selected from -COR3, CR3, -C- ~ , or-S-R3 ~2~;6~

O O O O O R R O
~ 14 14 11 and Z is selected from -COR60C-, -C-R6-C-, -C-N-R6-N--C-, O o Il 11 or -S-R -S
Il 7 ll O O
R3 is selected from an alkyl of 1-12 carbons, an aryl or substituted ary-l of 6-14 carbons, a cycloalkyl of 3-8 carbons, or an aralkyl of 7-9 carbons;

R4 and R5 are independently selected from hydrogen, an alkyl of 1-12 carbons, an aryl or substituted aryl of 6-14 carbons, an aralkyl of 7-9 carbons, a cycloalkyl of 3-8 carbons, or together can form an alkylene biradical of 4 to 7 carbons;

R6 is selected from an alkyl of 1-12 carbons, a cycloalkyl of 3-10 carbons, an alkylcycloalkylalkyl of 6-14 carbons or an aryl of 6-14 carbons, an alkylaralkyl or aralkylaryl diradical of 8-15 carbons and R6 may optionally contain ether linkages in the backbone; and R7 is biphenylene.

Detailed Description of the Invention Tert-octylhydrazine tl), a unique mono-substituted sterically hindered test-alkylhydrazine, is a very useful intermediate for preparing low temperature azo compounds.

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The tert-octyl group has a marked effect on lowering the half-life of azoalkanes and unsymmetrical azonitriles.
U.S. Patent 4,604,455 discloses a two step preparation of a mixture of unsymmetrical and symmetrical diazenes by first reacting at least two primary alkyl-, cycloalkyl-, or aralkylamines with sulfuryl chloride in the presence of an anhydrous-inert solvent until the mixture of the N,N'-disubstituted sulfamide product is formed. The amine hydrochloride byproducts are removed by an aqueous wash and the mixture of sulfamides are oxidized with basic bleach in a strongly basic medium to form the mixture of diazenes. If a low molecular weight secondary alkyl primary amine, such as isopropylamine, is used in conjunction with the tert-octylamine in this process, the low boiling symmetrical diazene is evaporated during the work up and a mixture of di-tert-octyldiazene and the unsymmetrical diazene remains with the unsymmetrical diazene being the major component. These unsymmetrical tert-octyl sec-alkyl (or primary alkyl) diazenes are also novel compounds.
The mixture of diazenes is heated in a chlorinated solvent, such as chlorobenzene, dichlorobenzene, or trichlorobenzene, at 120-150C. The di-tert-octyldiazene decomposes to liberate nitrogen, diisobutylene, and diisobutane Unexpectedly, the tert-octyl sec-al~yl (or ;4B4 primary alkyl) diazene rearranges to a tert-octylhydrazone instead of decomposing. If there is any of the symmetrical secondary (or primary) azoalkane present, it will also rearrange to a hydrazone. Therefore, it is preferable to use a low molecular weight amine such as isopropylamine in the sulfamide reaction to eliminate this problem.
The unsymmetrical diazene rearr,anges readily (1-2 hours) to the extent of about 80-90%.
The tert-octylhydrazone can be extracted out of the chlorobenzene solution with dilute sulfuric acid. The tert-octylhydrazone forms the sulfuric acid salt which is water soluble, The tert-octylhydrazone can be partially extracted out of the chlorobenzene solution with hydrochloric acid. The tert-octylhydrazone forms the hydrochloride but the hydrochloride is soluble in the chlorobenzene solution and only partially goes into the aqueous layer. Therefore, it is advantageous to extract the tert-octylhydrazone out of the chlorobenzene layer with dilute sulfuric acid. The di-tert-octyldiazene decomposition produc-ts and the unrearranged diazene remain in the chlorobenzene layer. The chlorobenzene layer is separated and can be recharged with fresh diazene mixture and the rearrangement repeated.
Upon neutralization of the sulfuric acid solution, the tert-octylhydrazone is obtained. Usually a small amount of hydrolysis occurs and the tert-octylhydrazone is contaminated L2~;G484 ~
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with some tert-octylhydrazine and the corresponding ketone.
If the mixture is refl~Yed, the free tert-octylhydrazine will react with the ketone to reform the tert-octylhydrazone.
If the sulfuric acid solution is heated, the ketone that forms is remQved by dis~illation, pre~erably under reduced pressure; the ter~-octylhydrazone will hydrolyze completely to an aqueous solution of tert-octylhyrazine sulfate.
The pure salt can be obtained by evaporation of the water. The hydrolysis is preerably c~rried out under ~0 reduced pressure to prevent dealkylation of the tert-octylhydrazine and formation of hydrazine sulfa~e. The hydrolysi`s of tert-octylhydrazone hydrochlorides can be carried out in similar fashion.
~he tert-octylhydrazine salt solution can be neutralized with an inorganic base, such as sodium or potassium hydroxides, carbonates, or bicarbonates, to form the free tert-octylhydrazine. ter~-Octylhydrazine has poor water soLubility and separates out of solution as an organic layer.
It c-an be taken up in hydrocarbon solvents, such as pentane or hexane~ dried, and heated to evaporate off the soIvent., tert-~ctylhydrazine has a very obnoxious and pungent odor so it is advisable to store it as an acid salt. The free base is probably more toxic than the acid salts so that care should be e~ercised when handling the free tert-octylhydraz:ine.

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~'-If the diazene mi~ture con~ained any of the cymmetrical di-sec-alkyl ~or primary alkyl) diazenes and it was not ;-removed before heating the diazene solution in the chlorinated solvent, the tert-octylhydrazone would be contaminated wi-th the corresponding sec-alkyl (or primary alkyl~ hydrazone and the tert-octylhydrazine would be :
contaminated with some o the corresponding primary secondary alkylhydrazine. This is not a problem when isopropylamine is used with t-octylamine in the sulfamide reaction.
~0 tert-Octylhydrazine is-useful as an intermediate for low ~-temperature azo compounds such as 2-tert-octylazo-2-cyano-.. ~., propane,`as an antioxidant, as an antiozonant, and as a ~
1~,,,,7/,,.,U',-,~' pharmaceutical intermediate. '! , .' -~he acid salts of tert-octylhydrazine (II) are readily lS prepared by reacting tert-octylhydrazine with an equi-molar amount of the desirèd acid. This can be done in aqueous solutions, and, in most cases, an aqueous solution of the salt will result. The acid can also be added to a hydrocarbon solution of tert-octylhydrazine and the hydrocarbon, preferably pentane or hexane stripped off to leave the salt. The hydrochloride or sulfate salts can also :
be prepared by reacting tert-octylhydrazones with an equi-molar amount of the acid and by stripping off the ketone that forms as described earlier. ~-In addition to being convenient forms of storing the oxygen sensitive tert-octylhydrazine, the salts are efficient ,`.

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L; ' foaming agents or polyester resins according to the method :--described by ~amens (U.S. Patent 4,393,148). -The tert-octylhydrazones (III) are generally prepared by reacting tert-octylhydrazine (I) with a ketone or aldehyde.
S With most aliphatic ketones and aldehydes, the reactlon is -usually carried out by neutralizinG an aqueous solution of tert-octylhydrazine sulfate (or hydrochloride), adding an equi-molar amount of the ketone or aldehyde, and refl~Ying the a~ueous mi~ture for about an hour. The ex~ent of I0 reaction can be foIlowed by gas chromatography. In the case of less reactive ketones, such as acetophenone, it is desirable to run the reaction in an inert solvent such as toluene and drive the reaction by azeotroping off the water that orms. The reaction can be catalyzed by adding a small amount of para-toluenensulfonic acid.
The tert-octylhydrazones (III) (Rl is not H and R2 is not C6H5) are useful in the synthesis of low temperature azo compounds. Hydrocyanic acid can be added across the double bond and the resulting hydrazonitrile oxidized to the corresponding a~onitrile.
The tert-octylhydrazides (IV) and (V) can be prepared by reacting tert-octylhydrazine with acid chlorides or diacid chlorides in~the presence of an acid acceptor. These ~
compounds are useful as blowing agents. They may be oxidized ~;
25 to the corresponding azo compounds which are useful as ~
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blowing agents and as initiators for the polymerization of vinyl monomers.
The tert-octyl substituted carbazates can be prepared by reacting tert-octylhydrazine with chloroformates or bis chloroformates in the presence of an acid accepter. These compounds are also useful as blowing agents. ~hey may be oxidized to ehe correspondin! azo esters which are useful as blowing agents and as initia~ors for the polymerization of vinyl monomers.
The substituted tert-octyl semicarbazides can be prepared by reacting tert-octylhydrazine with alkali metal cyanatesj isocyanates, diisocyana~-s, or substituted ureas.
These compounds are also useflll as blowing agents. They may b~e oxidized to the corresponding azo amides which are useful as blowing agents and as initiators for the polymerization of vinyl monomers. ~
The substituted tert-octyl sulfonylhydrazides and bis sulfonylhydrazides can be prepared by reacting tert-octylhydrazine with sulfonyl chlorides or disulfonyl chlorides in the presence of an acid acceptor. These compounds are also useful as blowing agents and as foaming agents for unsaturated polyester resins.

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Example I ~
Preparation of Cyclohe~yl t:ert-Octylidiazene , ,, Into a 1 liter 3-neck flask were added 40.8 grams (0.3 mole) of 95% tert-octylamine, 33.9 grams (0.325 mole) of cyclohe.xylamine and 300 ml of he~ane. The flask was equipped with a magnetic stirrer, thermometer, and Dean Stark trap connected to a reflu~ condenser. The flask was lowered into an 80C preheated oil bath and the he~ane solution was refl~Yed using the Dean Stark trap to remove water which was azeotroped cEf ~i~h ~exane rom t~e reac~ion mass for~I/2 hour. The water tha~ formed in the trap was i~`
separated and the he~ane layer added back to the reaction -flas~. The magnetic stirrer was replaced with a mechanical stirrer and the flask was equipped with a 25 ml dropping lS funnel, air condenser, and thermometer. ~he he~ane solution of the dried amine was cooled to 0C and 20.9 grams (0.15 mole) or 97% sulfuryl chloride was added dropwise from the dropping funnel over 20-30 minutes while holding the temperature below 15C. After the addition was completed, the reaction was warmed to 30C and stirred 1/2 hour at Z5-30'C. The reaction was diluted with water ~o dissolve v, ~

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the hydrochloride salts and transferred tO a separatory funnel. The aqueous layer was separated and the he~ane , layer was washed with I00 ml of 10% H2SO4 to remove any residual amine. The acid wash was separated and added to the aqueous layer for neutralization and recovery of amine.
The he~ane layer was transferred back to the 1-liter 3-neck flask and 0.5 grams of .~dogen 464 (a trademark to cover methyltrialkyl (C~-C10) ammonium chloride, marketed bv Aldrich Chemical Company) phase transfer catalyst and a solution of 40 grams (0.5 mole) of 50% sodium hydro~ide in 250 grams of 14.2% bleach were added. The flask was equipped~with a ma~netic stirrer, thermometer, and 5~;-distillina head connected to a condenser and receiver. The flask~was lowered into a preheated oil bath (~80C) and stirred viaorously ~ich the magnetic s~irrer. When the reaction mi~ture warmed up to 62C, the h~a~e began co distill, and o~idation began to occur. Ogidation was essentially completed by the time distillation ceased. The reaction mixture was stirred an additional hour at 85C
before cooling back to room temperature. The reaction mixture was diluted with 100 ml of hexane and transferred to a separatory funnel. The aqueous bleach layer was separated . - o ~6~ ~ '' ,..

and the hexane solution of the di.azenes was washed successively wi~h 100 ml poritions of water, 15% sodlum bisulfite solution, 10% H2SO4, and saturated sodium bicarbonate solution. The hexane solution was dried over S anhydrous sodium.sulfate, filtered, and heated ~o strip off ~.
the solvent on a rotary evaporator under reduced pressure.
The residue weighed 29,1 grams and was composed of approximately- 20% of di-ter~-oc~yldiazene, 12% of dicyclohe~yldiazene, and 65% of the de.sired cyclohexyl tert-octyldiazene.
- Subsequent runs were carried out wh-re the mole ratio of the cy-clohe.~ylamine and tert-ocrylamine were varied slightly. The results were summari7ed in ~he following Table. I

~3 iai~6~1~
-- .

Z o ~ ~, Z
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, In ,~, z ,n ~, c~
l O 1 .-,~

. I C3 ~O ~ CS~

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;~1 = ~ `* U~
I C ' .

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E.Yample II
Preparation of Isopropyl tert-Octyldiazene Several runs of isopropyl tert-octyldiazene were made using the procedure described in E~mple I but substituting isopropylamine for cyclohe~ylamine. The crude product was primarily a mi~ture of di-tert-octyldiazene and isopropyl tert-octyldiazene. This product did not contain any diisopropyldiazene. The reaction was run on a larger scale in a 2 liter 3-neck fIask employing 1.3 moles of isopropyl~amine, 1.2 moles of tert-octylamine, 0.6 mole sulfuryl chloride, 800 ml of he~ane, 1 ~ram of Adogen 464, and a soIl?tion of 300 grams of 50% sodium hydroxide in 1200 grams of 12% bleach. The product after workup weighed 66 grams and was composed of appro~imately 6S~/o isopropyl tert-octyldiazene and 25% di-tert-octyldiazene.

Example III
Preparation of Cyclohe~anone tert-Octylhydrazone and tert-OctylhYdrazine Hvdrochloride ~ = . ~ . .

A mixture of di-tert-octyldiazene (32.5%), dicyclohexyldi.azene (9%) and cyclohe~yl tert octyldiazene (53%) weighing 27.6 grams was diluted with 83 grams of o-dichlorobenz:ene and added to a 3-neck 250 ml round bottom flask. The flask was equipped with a magnetic stirring bar, .

refl~Y condenser, and nitrogen purge. The solu~ion was heated for 3~ hours at 120-125C. Gas chromatographic analysis indicated that about 75% of the cyclohe~yl tert-octyldia7ene had rearranged to cyclohe~anone S tert-octylhydrazone. The re~ction was cooled to room temperature and ~he dichlorobenzene solution e~tracted with 50 ml of 5% HCl. The acid e~tract was set as-ide and the diclorobenzene solucion recharged with an additional lS grams of diazene mi~ture and the solution heated ~or 2 hours at }0 120-130C. Gas chromatographic analysis indicated the cyclohe~yl tert-octyldiazene had rearranged about 70% to the hydrazone. The soIution was cooled to room temperature and extracted with another 50 ml of 5% HCl. The acid e~tract was added to the first extract and the dichlorobenezene solution recharged with an additional 14.4 grams of the diazene mixture. The dichlorobenzene had rearran~ed about 70% to cyclohexanone tert-octylhydrazone. The dichlorobenzene solution was heated for 2 hours at 120-125C and cooled back to room temperature. Gas chromatographic analysis indicated that the cyclohexyl tert-octyldiazene had rearranged about 70% to cyclohexanone tert^octylhydrazone. The dichlorobenzene solution was extracted with another 50 ml of 5% HCl and the acid eætracts were combined. The acid extracts were washed twice with pentane to remove any residual dichlorobenzene. The acid was then neutralized with 60 ml of 10% NaOH and extracted twice with 5Q ml of pentane.

The pentane extracts were combined and analyzed by gas chromatography. The pentane solution contained a mixture of tert-octylhydrazine (~75~) and cyclohexanone tert-octyl-hydrazone (~20%).
Since the hydrolysis of the hydrazone was incomplete, the pentane solution was treated with 10% HCl (30ml) until a pH of 0.5 was obtained. The aqueous solution was separated and allowed to stand overnight. Pure tert-octylhydrazine hydrochloride was obtained by stripping the solution to dryness and recrystallizing the residue from ethanol. The recrystallized hydrochloride was a white crystalline solid which melted at 141-143C with gassing.
Neutralization of the dichlorobenzene solution with sodium bicarbonate solution generated a considerable amount of cyclohexanone t-octylhydrazone indicating that cyclohexanone t-octylhydrazone hydrochloride is quite soluble in dichlorobenzene and is not extracted out of the dichlorobenzene very efficiently with water. The residual cyclohexanone tert-octylhydrazone was efficiently extracted out of the dichlorobenzene with dilute sulfuric acid.

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E~ample :[V ~-Preparation of Acetone tert-Octylhydrazone and ter~-Octylhydrazine Sulfate A mixture of di-tert-octyldia~ene (27%) and isopropyl S tert-octyldiazene (65%) weightin~ 33.5 grams was dilu~ed with ~-67 grams of chlorobenzene and added to a 3-neck 250 ml round bottom flask. The flask was equipped-with a magnetic stirring bar and refl~Y condenser and was purged with a steady stream of nitrogen. The solution was gently refl~Yed lO for 3 hours at 134C and then cooled below 20C. Gas !~
-chromacographic analysis indicated that the isopropyl tert-oct~ldiazene had rearranged about 88% to acetone tert-octylhydra20ne. The reaction mi~ture was dilu~ed with 75 ml~of water; 20 grams of 70% H2S04 were added dropwise.
The mi~ture was stirred vigorously for 5 minutes and transferred to a separatory funneL. The 'aqueous layer was separated and the chlorobenzene layer was washed with an additional 25 ml of water; ~he aqueous wash was added to the acid layer. Neutralization of a small sample of the 2Q chlorobenzene layer indicated the absence of any acetone tert-octylhydrazone indicating that it had all been e~tracted into the acid layer. The acid layer was washed with 50 ml of hexane to remove any residual ch}orobenzene. Neutralization of a small sample of the acid layer indicated that 60% of the acetone tert-octylhydrazone had hydrolyzed to tert-octyl-hydrazine.

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The aqueous acid solution weighed 141 grams. It was then stripped for 1~ hours on a rotary evaporator at 30-40C
under reduced pressure. The final aqueous solucion weighed 62.8 grams and contained Z4.9% tert-octylhydrazine (iodometric titration) which was present as ~he sulfa~e.
~eutralization of a small sample of the acid solution indicated the presence of a small amount (~5%) of unhydrolyzed acetone tert-octylhydrazone in the tert-octylhydrazine.

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E~ampL~
` Preparation o~ t -OC ~yi:nvd~azine 1`

.
- ~ mi~ture of di-tert-octvld~aze~e (~') and isopropyl tert-octyldiazene (~2h) weighin~ ~7.2 arams was diluted with 65 grams of chlorobenzene and refl~ed for 3 hours at 134C
as in ~Yample IV. The reaction mixture was cooled to 20C
and diluted with 100 ml of water; 14 grams of 70% H2SO4 was added dropwise. The aqueou~ layer was worked up as in Example IV and then stripped for 1 hour at 30-40C on a rotary evaporator under reduced pressure. This solution of tert-octylhydrazine sulfate weighed 35.2 grams. A small sample was made basic and e~tracted with hexane. A VPC scan of the e~Ytract indicated that the hydrolysis was completed.
The aqueous solution was diluted with 100 ml of water and made strongly basic by the addition of 24 grams of 50%

2~
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, ~aOH. The mi~ture was cooled to 20C and e~tracted with 100 ~
ml of pentane. The pentane e~tract was dried over anhydrous sodium sulfate, filtered, and heated to strip of the pentane. The residue was a yellow liquid which wei~hed 11.0 grams. Gas chromatographic analysis indicated that the product was approximately 85% tert-octylhydrazine. .~ttemp~s to vacuum distill the product led to gassing and slow decomposition around 50C.

~Yample VI ~
10Pre~aration of Methyl Ethyl Ketone tert-Oc~vlhvdrazone '`
., .. , , ,~

rO a solution fo 24.2 grams (0.10 mole) of ter~-octyl-hydra~ine sulfate ~prepared as in E~ample IV) in 48.3 grams of water in a 3^neck 250 ml round bottom flask, were added 25 ml of water, 8.6 grams of methyl ethyl ke~one, and 20 grams of 50% sodium hydro~ide. The flask was equipped with a magnetic stirrer~ thermometer, and refluY condenser and was heated in an oil bath. The reaction mi~ture was refluYed gently for 1 hour, cooled to 60C, ànd transferred to a separatory funnel. ~he aqueous layer was drained off from the organic layer; the organic layer was then diluted with 50 ml of hexane, dried over anhydrous Na2SO4, filtered, and heated to strip off the solvent on a rotary evaporator at 30C under reduced pressure. The crude product weighed 17.5 grams and assayed about ~0% by gas chromatographic analysis.

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The corrected yield of methyl ethyl kecone tert-octylhydrazone was appro~imately 80%. There was no methyl ethyl ketone ketazine present indicating that the tert-octylhydra~ine sulfate was not contaminated with any hydrazine sulfate.

E.Yample VII
Preparation of the Oxalic .~cid Salt of tert-Octvlhydrazine To a solution of 5,grams of o~alic acid dihydrate in 15 ml of ethanol and 20 ml of e~her were added 5 gram,s of methyl ethyl ketone tert-octylhydrazone. The mi~Yture was stirred for 1 hour at room temperature. A white precipitate began to form ,after 10 minutes. After the hour stirring period, the white solid was filtered off, washed with 5 ml of ethanol, , pulled semi-dry on the filter, and air dr'ied on a tared watch glass. The product weighed 2.2 grams and had a melting point of 128-130C.
A second crop of 1.0 gram was obtained by concentrating the filtrate and refiltering it~
The filter cake was slurried in water, neutralized with caustic, and e~tracted with hexane. The hexane e~tract was dried over ~a2SO4, filtered, and heated to strip off the hexane on a rotary evaporator under reduced pressure. The residue weighed 1.0 gram and was identified as tert-octyl-hydrazine by gas chromatographic retention time.~

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E~ample VIII ,-Preparation of l-~ert-Octyl-2-etho~ycarbonylhydrazine To 62 grams of a solution containing 3.84 grams (O.026 mole) of tert-octylhydrazine (as ~he sulfate) was added 5enough 50% NaO~ (6.3 grams) to bring the pH up to 9. Then 5 grams of sodium carbonate were added and the mi~ture cooled ~o 10C. The tert-octylhydrazine separated out of solution and 25 ml of he~ane were added. The mi~ture was stirred and a solution of 2.8 grams (0.026 mole) of ethyl chlorofomate in 5 ml of he~ane was added dropwise over L hour whi~e holding the tempèrature at 10-15C. Ihe addition was monitored by gas chromatography; when about 80% of the chloroformate -solution had been added, it appea~red that all the tert-octylhydrazine had been consumed. Therefore, the addition was stopped to prevent diacylation. The reaction mixture was transferred to a separating funnel and the aqueous layer was separated. The-he~ane solution was washed with saturated sodium bicarbonate solution and water, dried over anhydrous sodium sulfate, filtered, and heated to strip off the he~ane on a ro~ary evaporator under reduced pressure.
The residue was a light yellow liquid weighing 3.7 grams.
The infrared spectrum of the residue had a strong broad l~H
peak at 3315 cm 1 and a very strong broad carbonyl peak a~
1710 cm~l.

24 ~ , . ' - ` - .

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The product was oxidized~to the corresponding aZG ester with 30 grams of 12% bleach. The product weighed 3.8 grams and was 93% pure by gas chromatographic analysis. The infrared spectrum of the oxidized product did not contain any peaks in the NH region (3200-330Q cm 1) and the carbonyl peak -was very sharp and shifted to 1770 cm 1, The azoester was an orange liquid and gassed moderately from 1~0C tO 180C and rapidly above 180C. It would be useful as a blowing agent for vinyl resins.

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~ample I~
- f,~
`~ Preparation of l-ter~-Oc~ylsæmicar'?azide ~
..
- Into a 125 ml erlenmeyer flask were weiched 20.9 grams of a solution which contained 5.2 grams (0.036 mole) of ter~-octylhydrazine as- the sulfate. .~ magnetic stirring bar was added and the so~ution was partially neutralized by adding

3.25 grams (0.04 mole) of 50%.sodium hydroxide. ~ solution of 5.24 grams (0.065 mole) of potassium cyanate in 20 ml of water was slowly added over 15 minutes while holding the temperature between 20C and 25C. A~ter the addition was completed, the reaction mixture was stirred one hour and the solids that formed was fil~ered off. The filter cake was washed with pentane and air dried. The dried filter cake weighed 3.7 grams and had a meIting point of 176-178C.
'.

A second crop of product was obtainea by recharging the aqueous filtrate with 2 grams of potassium cyanate and stirring the mixture an additional hour. The solids that formed were filtered off and air dried. The second crop weighed 2.2 grams and had a melting point of 175-177C. The infrared spectrum of the product contained MH bands a-t 3200 cm 1, 3250 cm 1, and 3450 cm 1 and a strong carbonyl band at 1660 cm and an amide II band a~ 1580 cm The l-tert-octylsemicarbazide was oxidized to tert-octylazoformamide with neutral permanganate in 22% yield. The tert-octylazoformamide was a yellow crystalline solid which melted at 63-64C. It began gassing at 110-120 C and gassed rapidly above 130C.

Example X
Preparation of l-tert-Octyl-2-para-toluenesulfonylhydrazine Into a 3-neck 250 ml flask were weighed 20.9 grams of a solution which contained 5.2 grams (0.036 mole) of tert-octylhydrazine as the sulfate. The solution was diluted with 50 ml of water; 28.8 grams t0.072 mole) of 10~ sodium hydroxide and 10.6 grams (0.1 mole) of sodium carbonate were then added. The flask was equipped with a magnetic stirring bar, thermometer, and dropping funnel and was placed in a cold water bath. In the meantime, 7.6 grams of para-toluenesulfonyl chloride were dissolved in 50 ml of toluene ~7 .æ~

and added to the dropping funnel. The toluene solution was added to the rapidly stirred aqueous solution while holding the temperature at 15-20C. The addition required 15 minutes and the reaction mass was stirred an additional hour after - S the addition was over. White soli.ds formed during the addition period. At the end of the stirring period, the reaction migture was filtered and the filter cake was stirred in he~ane, refiltered, and air dried. The whit~. powder weighed 7.3 grams. The product decomposed with rapid gassing upon melting at 108-110C. L

!
E~ample ~I
Preparation of l-tert-Octyl -2-meta-chlorobenzoylhydrazine Into a 3-neck 250 ml flask were weighed 18.0 grams of a solution which contained 4.9 grams (0.03 mole) of tert-octylhydrazine as the sulfate. The solution was diluted with50 ml of water; then 6.2 grams (0.078 mole) of 50% sodium hydroxide were added to raise the pH to 9 and then 4.24 grams (0.04 mole) of sodium carbonate were added. The flask was equipped with a magnetic stirring bar, a thermometer, and a ~0 dropping funnel containing 4.9 grams (-0.03 mole) of meta-chlorobenzoyl chloride. The reaction mixture was diluted with 25 ml of hexane and then with rapid stirring the meta-chlorobenzoyl chloride was added dropwise over 10 minutes while holding the temperature between 18 and 25C. After the addition was completed, the reaction was stirred an additional 30 minutes and the white solid that formed was filtered off. The filter cake was slurried in a mixture of 100 ml of hexane and 100 ml of warm water and refiltered.
The filter cake was pulled semi-dry on the filter and then air dried to constant weight. The product was a white powder that weighed 7.3 grams and had a melting point of 133-137C.
The infrared spectrum of the product had a s-trong NH band at 3200 cm 1 and a StrOilg sharp carbonyl band at 1620 cm 1 Example XII
Preparation of Terephthaloylbis(2-tert-octylhydrazide) Into a 125 ml erlenmeyer flask were weighed 3 grams of 85~ tert-octylhydrazine, 20 grams of water, and 2.1 grams of sodium carbonate. The flask was equipped with a magnetic stirring bar and thermometer; 25 ml of ether was then added.
The mixture was stirred rapidly and a solution of 1.8 grams of terephthaloyl chloride in 25 ml of ether was added dropwise while holding the temperature between 25-30C.
White solids formed immediately upon adding the ether solution. The reaction mixture was stirred an additional 1/2 hour and filtered. The filter cake was rinsed with additional ether, reslurried in warm water, and refiltered.
The filter cake was pulled semi-dry on the filter and air dried to constant weight on a tared watch glass. The dried i3 Q
~- - 28 -product weighed 3.5 grams and melted at 242-245C with decomposition. The infrared spec:trum had NH bands at 3240 and 3280 cm 1 and a sharp carbonyl band at 1630 cm 1.

- - Example XIII
Prepration of 1,13-Di tert-octyl-1,2,12,13--tetraazo-3,11-dioxo-4,7,10-trioxo-tridecane Into a 135 ml erlenméyer flask were weighed 4 grams of 85% tert-octylhydrazine, 20 grams of water, and 2.65 grams of sodium carbonate. The flask was equipped with a magnetic stirring bar and thermometer; 25 ml of hexane was then added.
The mixture was stirred rapidly and 2.65 grams of diethylene glycol bis chloroformate were added dropwise while holding the reaction temperature between 20 and 30C with a cold water bath. After the addition was completed, the reaction mixture was stirred an additional hour a~ room temperature.
A gas chromatographic scan indicated that all of the tert-octylhydrazine had reacted. The mixture was transferred to a separatory funnel and the aqueous layer was separated. The hexane layer was washed with 25 ml saturated sodium bicarbonate solution, dried over anhydrous sodium sulfate, filtered, and heated to strip off the hexane on a rotary evaporator ~mder reduced pressure. The residue was a light yellow liquid weighing 5.5 grams. The infrared spectrum of ~he produc~ h~d ~ ~trong ~road NH b~nd a~ 3300 cm and a s~rong broad carbonyl band a~ 1700 cm 1, The bis hydrazo ester was oxidized eo che corresponding bis azoester by stirring a met~lylene chloride solu~io~ o~ ~he .5 hydrazo ester wich 50 grams o~ bleach for about 4 hours. The ;. methylene chloride solution of ~he azoescer was washed wi~h saturated sodium bicarbonate ar~d water, dried over anhydrous sodium sulfaee, filcered, and heated eo s~rip o~f the methylene chloride on a rotary evaporaeor under reduced pressure. The residue was a dark yellow-orange liquid weighing 4.7 grams. The infrared spec~rum of the-azoes~er.
showed che absence of any .~H bands and ~he carbonyl band was , sharp and shif~ed ~o 1760 cm~l. The azoester gassed mildly ; from 140-150C, moderately from 150-165C, and rapLdly above 0C.

ample ~IV
~oaming an Unsa~uraced Polyescer Resin with Tert-Octylhydrazine Derivacives The unsacurated polyes~er resin was Laminac 4123*(an orthophchalic acid-based resin concaining approximacely 30%
; scyrene monomer, markeced by U.S.S. Chemicals). The resin was modified by adding an addicional 5 phr scyrene monomer and 1 phr Dow Corning 193* surfactant.
The resin and all ocher componencs e~cepc che pero~ide cacalysc were weighed inco 9-ounce wa~ed paper cups and * trade mark ~4~

~ - 30 -~ , .

blended using a high shear electric miYer. The pero~ide catalyst was then added and blended in; at this time an electric timer was activated in order to obtain gel times (time to peak foaming). ~fter mi~ing at high shear for about - 5 10 seconds, 3Q gram portions of the ml~tures were poured into 3-ounce paper cups and allowed to foam. Gel ~imes and foam densities were determined from these samples. Densities wer-determined by the water displacement method. The results are summarized in the following Table II.
~he cured but unfoamed Laminac 4123 resin has a density greater than 70 lbs./cu.f~

j..

Table II
~oaming an Unsaturated Polyester Resin tert-Octylhydrazine .~ert C8H17 NH2 HCl ~Y# ~ ~# ~1 Derivative (ExamPle#) 5Parts derivatrve/hundred parts 0.86 1.45 1.3 . resin phr 45% FeC13 0,4 0 4 phr 6% Cobale Neodecanoate 0-05 0.1 0.3 phr S% Copper Naphthenate ~ 4 phr Lupersol Delta ~-9~ 3.0 3.0 3.0 g~l cime in minuces 2.0 2.0 3.0 :,. ;
density lbs./cu. ft. 33 41 41 ~.

* Trade mark for a commercial formulation of Methyl Ethyl ~ :
Xetone Peroxide and Hydrogen Peroxide in D~methyl Phthalate` -Lucidol Division of Pennwalt.

9~

Claims (4)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY OR PRIVILEGE
IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A tert-octylhydrazine of the structure

2. A tert-Octylhydrazine salt of the structure A

where n is 1 or 2, with the provisos that when n is 1, A is selected from HC1, HBr, H2SO4, H3PO4, and where R is selected from H, CH3, C2H5, C3H7, i-C3H7, and C6H5, and when n is 2, A is selected from H2SO4, and

3. The salt of Claim 2 where n is 1 and A is HC1.

4. The salt of Claim 2 where n is 1 and A is H2SO4.