US2798793A - Polynitrophenols - Google Patents

Description

United States Patent I POLYNITROPHENOLS Carl E. Moore, Chicago, Ill.

No Drawing. Application September 9, 1954,

Serial No. 455,075

7 Claims. (Cl. 23-430) This invention relates to reagents in-the formoftrini trophenols.

The separation or qualitative analysis for barium,

strontium and calcium is particularly difficult, a'ndthe primary object of the present invention is to enable this;

to be accomplished with relative ease by means of a 3- methyl-S-npropyl-trinitrophenol reagent that will precipitate barium in relativelylargequantities while having but slight precipitating action on strontiumand calcium in a mixture containing the three. A further object of the present invention in this connection is to enable analysis to be made for cerium, lanthanum, beryllium, cesium, aluminum, lead, copper, chromium and iron by means of a 3-methyl-S-n-propyltrinitrophenol reagent that exhibits contrasting precipitates for these metals.

A further object of the present invention is:to1 enable lanthanum or lead to be determined in-a mixture containing lanthanum or lead or both inthepresence of. one or.

more of the following: Nat, Li Cur Ca+t, Mg Ni A1+++ H Z M c cd++ Fe++, Cs+, NH4+ by means. of areagent in the: form of 3- isopropyl-2,4,6-trinitrophenol;

Other andfurther objects of. the present: invention will be apparent from the following; descriptionwand claims which, by way of illustration, show preferredembodiments of the invention and the principles thereof and; .what I now consider to bethe best modesinwhiehI have contemplated applying those principles. Other andfurtherobjects of the invention embodying the same or equivalent principles may be used and changes maybe made as desired by those skilled in the art without. departingfrom the present invention and the purview of the appended claims.

I Synthesis of 3-n 1ethyl-5-n-pr0pyltrinitrophenol In each of three 500 cc. flasks place 210 cc. (1.6 mole) of ethyl acetoacetate. Chill in an ice-salt bath.and,add 0.77 mole butyraldehyde to each flask. Cool-to C. and add, with shaking, to each flask amixturerconsisting of 3: cc. piperidine and .5 cc. ethanol. Maintain eachfiask in an ice-salt bath for six hours, combinethe contents of the three flasks and refrigerate for three days while adding an additional mixture of 3 cc. piperidine and5 cc. ethanol each day. After completion of the foregoing, allow the system to stand one day at room temperature to obtain the following ester product: t

The yield, a crude bis-ester (viscous oil), is melted on a steam bath and poured into a mixture of 600 cc. acetic acid and 40 cc. concentrated sulfuric acid. To this is added about g. of boiling chips. Reflux for one hour. Pour the mixture (with stirring) into 2 litres of ice-water, establish separate layers by adding ether and decant to obtain the organic layer. The organic layer thus separated is stirred with 1200 cc. water and neutralized at the same 2,798,793 Patented July 9, 1957 ice onnooon no The aforesaid ether solution is heated gently under reduced pressure until all the ether is evaporated, and to the carbethoxy residue is added 1020 cc. water, 180 cc. ethanol, and 130 g. NaOH. The resultant solution is then heated on a steam bath with stirring until the ester is dissolved. Reflux for 15 minutes, and then carefully acidify with a solution of cc. concentrated sulfuric acid in 200 cc. water while cooling the flask with a stream of water; The-acid is added at a rate compatible with the evoluton of C02. The acidified mixture thus obtained is then refluxed for 15 minutes, cooled to room temperature and the layers separated. The crude product thus obtained is diluted with ether and washed with two 100 cc; portionstof 5%-NaOH solution followedzby 100cc. of 5% aqueous-acetic. acid. The ether solution is dried over anhydrous sodium sulfate and distilled under reduced pressure to obtain the following product (3-methyl-5-npropyl-Z-cyclohexene-l-one) having a boiling point of -113C. at9mm.:

5 g. of the 3-methyl-5-n-propyl2-cyclohexene-l-one product is mixed with 75 cc. trimethyl benzene (mesitylene-Eastman Kodak crude redistilled) and 1.5 g. of a standard 5% palladium-carbon catalyst. The mixture is subjected to a vigorous reflux at C. for 2 hours and then cooled to 50 C. The catalyst, which cannot be reused, is removed by filtration, and washed with four 5 CCJPOItlOIlS of hot ethyl acetate. The product in solution is subjected to liquid-liquid extraction with. three 40 cc. portions of 10% NaOH solution. The combined extracts are washed with 40 cc. pentane, then diluted with 100 cc. water, and 5 cc. of concentrated hydrochloric acid are added thereto. The acidified solution is chilled in an ice bath, further acidified with dilute hydrochloric acid and re-chilled for several hours. The product is removed by ether extraction, and the ether is evaporated under reduced pressure to obtain the following:

To nitrate the 3-rnethyl-5-n-propyl product, 3 to 4 g. thereof are acidified with 30 cc. of concentrated sulfuric acid, stirred and cooled. 30 cc. of concentrated nitric acid are added dropwise while cooling and stirring. The resultant mixture is poured over approximately 50 cc. of ice. When the ice melts, the product in the form of red-black amorphous crystals is filtered ofl. These are redissolved in 25 cc. of hot ethyl alcohol. Then 25 cc. of a 5% NaOH solution are added followed by the addition of 50 cc. of a saturated KCl water solution. The

A solution of the aforesaid potassium salt.

a following product in the form of bright yellow crystals is cooled and filtered oif:

N02 NO: 7

CH: CHgOHn-,QH;

V 7 N02 11 Preparation of 3-methyl-5-n-pr0pyltrinitrophenol reagent Add one-half g. of 3-methyl-5-n-propyl-trinitrophenol prepared as above to 15-20 cc. water to produce approximately a 3% solution, and add 1 N. NaOH thereto until the pH is adjusted to 6.5. The reagent thus prepared will produce the following precipitates from an aqueous solution:

Relative Amount of Precipitate Slight.

Minute.

Use of the foreging reagent produces an oil in the presence of the following metals: Be++, Cr++, and Fe+++.

HI Synthesis of 2,4,6 trinitro-S-isopropylphenol I OH: N02

Analysis.-Calci1lated for C9H9N307: C, 39.86; found C, 40.27; H, 3.34; found, C, 3.02; N, 15.5; found, N, 15.2.

IV Preparation 0 2,4,6 trinitr0-3-is0pr0pylphenol reagent For analytical work, a sodium salt is prepared of the 2,4,6 trinitro-3-isopropy1phenol. To this end, and aqueous solution of the above identified isopropylphenol is first rendered basic by the addition of NaOH, and to this is added a concentrated water solution of NaCl which precipitates the sodium salt of 2,4,6 trinitro-B-isopropylphenol as bright yellow crystals which may be filtered off. Qualitative tests may be performed by adding a saturated water solution of the sodium salt to dilute aqueous solutions of chlorides or nitrates of the cations being tested with the following results:

Cation Result Nat. Negative. Li+--. Do. 811: Be. a 0. Mg Do. Ni"- Do. fil tm go. 0. 0 Do. Zn D0. Mn- Do. Or+++ Do. Od .Do. Fe be. 0s Do.

NH4+ Do. La Positive. lb Do.

Ammonia complexes of the following ions give well defined crystalline precipitates:

I claim:

1. A trinitrophenol derivative selected from the group consisting of 3-methyl 5-n-propyltrinitrophenol, 2,4,6- tn'nitro-isopropylphenol and the sodium salts thereof.

' 2. A reagent for the qualitative separation of barium,- strontium and calcium consisting of the sodium salt of 3-methyl-5-n-propyltrinitrophenol.

3. A reagent for the qualitative separation of lanthanum and lead consisting of the sodium salt of 2,4,6-trinitroisopropylphenol.

4. 2,4,6-trinitro-isopropylphenol.

5. 3-methyl-5-n-propyltrinitrophenol.

' 6. The method of qualitatively separating barium from barium, strontium and calcium comprising, preparing a reagent in the form of an aqueous solution of the sodium salt of 3-methyl-5-npropyltrinitrophenol, and adding said reagent to a mixture of barium, strontium, and calcium contained in a solution which contains non-interfering metals to precipitate only barium in large quantities.

7. The method of performing a qualitative analysis for a metal selected from the group consisting of lanthanum and lead comprising, adding a reagent consisting of an aqueous solution of the sodium salt of 2,4,6-trinitroisopropylphenol to a solution suspected of containing an ion of said metal group, the last-named solution being free of interfering material.

References Cited in the file of this patent V .Cousin et al.: Chem. Abstracts, vol. 31 (1937), pg.

Claims (1)

1. 7.THE METHOD OF PERFORMING A QUALITATIVE ANALYSIS FOR A METAL SELECTED FROM THE GROUP CONSISTING OF LANTHANUM AND LEAD COMPRISING, ADDING A REAGENT CONSISTING OF AN AQUEOUS SOLUTION OF THE SODIUM SALT OF 2,4,6-TRINITROISOPROPYLPHENOL TO A SOLUTION SUSPECTED OF CONTAINING AN ION OF SAID METAL GROUP, THE LAST-NAMED SOLUTION BEING FREE OF INTERFERING MATERIAL.