US3380457A - Tobacco product - Google Patents

Description

United States Patent 3,380,457 TOBACCO PRODUCT Joseph N. Schumacher, Wilmer A. Rohde, and Donald L.

Roberts, Winston-Salem, N.C., assignors to R. J. Reynolds Tobacco Company, Winston-Salem, N.C., a corporation of New Jersey No Drawing. Filed Aug. 2, 1965, Ser. No. 476,687 12 Claims. (Cl. 131-17) This invention relates to a tobacco product and has for an object the provision of a composition and process for improving the flavor and aroma of tobacco and tobacco smoke.

It is well known in the tobacco art that the flavor and aroma of the tobacco product and the smoke from the tobacco are very important considerations in so far as the ultimate consumer is concerned. Considerable efforts are exerted by the manufacturers of tobacco products to provide a product that will be acceptable to the consumer, particularly as regards flavor and aroma characteristics. It has been the common practice in the tobacco industry to prepare blends of domestic and oriental t0- baccos in order to provide smoking tobacco which has a pleasing flavor and aroma before and during smoking. However, such a procedure is costly and may at times become prohibitive in the event that certain types of tobacco may be in short supply. Accordingly, it is a further object of this invention to provide a new class of additive materials which when applied to the tobacco products improve and enhance the flavor and aroma of these products and the smoke emitted therefrom thereby increasing or enhancing the pleasure and other values that may be derived by the consumer from the use of these products.

A further object of this invention is the provision of a process for enhancing or otherwise improving the flavor, aroma and other qualities of certain domestic, oriental, reconstituted or synthetic tobaccos which may be deficient in said flavor or aroma or other qualities.

An additional object of this invention is to provide a process of preparing a smoking ,tobacco or product which when smoked has an enhanced flavor or aroma.

A still further object of this invention is the provision of smoking products, such as cigarettes, cigars or pipe tobacco, and a process for forming same whereby the flavor and aroma before and during smoking are improved or enhanced.

Further and additional objects will appear from the following description and the appended claims.

'In accordance with one embodiment of .this invention a tobacco product is provided which has been treated with a small amount of a compound selected from the group of compounds having the formula Formula I wherein R R and R are selected from the group consisting of hydrogen and alkyl groups, with at least one of such substituents being alkyl. Thus, the tobacco additives of the present invention are alkyl substituted, saturated or unsaturated 6 lactones. Preferably the alkyl radicals present in the tobacco additives are lower alkyl radicals of 1 to 6 carbon atoms. Thus, the alkyl substituents can be, for example, methyl, ethyl, propyl, isopropyl, normal butyl, isobutyl, pentyl or hexyl.

The following specific examples illustrate the preparation and characteristics of representative tobacco additives of the present invention. It will be appreciated, however, that this invention is not limited to the specific process 3,380,457 Patented Apr. 30, 1968 "Ice by which the compounds may be prepared. All temperatures are expressed in degrees centigrade.

Example I.Synthesis 0f 3-is0pr0pyl-fi-valerolactone (a) 3-z's0propyl glutaric acid.-To a vigorously stirred solution of 94 grams of u-cyanoacetamide in 700 milliliters of water at 15 C. were added 35 grams of isobutyraldehyde and 10 grams of piperidine. Stirring was continued for 3 hours while the reaction mixture was kept between l015 C. The reaction mixture was then placed in the freezer overnight (16 hours). After allowing the solidly frozen reaction mixture to thaw the fine, white crystals were collected on a Buchner funnel, washed and dried to yield 81.8 grams (82% of theory), of the 0:,11- dicyano-fl-isopropyl glutaramide (M.P. 152l54). Without further purification grams of this product was placed in a 1 liter round bottom flask equipped with a reflux condenser; 300 milliliters of concentrated hydrochloric acid was added and the solution was brought to gentle reflux temperature. After 6 hours refluxing another 25 milliliters of hydrochloric acid was added and refluxing continued (another check after 12 hours indicated the hydrochloric acid content was still high) for a total of 29 hours. This hot solution was then poured into an evaporating dish, where upon cooling a volume of light tan solids precipitated out of solution. The solids were filtered from the solution in a Buchner funnel and thoroughly washed with methylene chloride (they were mostly soluble in this organic solvent). Extraction of the aqueous extraction solution with methylene chloride furnished 19 grams of the ,B-isopropyl glutaric acid, melting point 98-101". A further extraction of the aqueous reaction solution with methyl ethyl ketone provided another 33 grams of the title compound; total 52 grams, 83% of theory. A 1 gram sample of the crude isopropyl glutaric acid was recrystallized from 10% hydrochloric acid to raise its melting point to 103104 [lit. 102].

(b) 3-is0pr0pyl-glutaric anhydride.-A 500 milliliter round bottom flask was equipped with reflux condenser and heating mantle. The flask was charged with 49 grams of the crude 3-isopropyl gluartic acid and 50 milliliters of acetic anhydride and brought to reflux temperature for 6 hours. The refluxed solution was then transferred to a 25 O-milliliter flask equipped with a 15 centimeter Vigreaux column distilling head. After distilling oi the acetic acid at atmospheric pressure the system was brought under reduced pressure. After removal of the remaining acetic anhydride 44.3 grams of the title compound were collected; boiling point 122-126/750;t. A previous 2 gram fraction, collected at boiling point 117/ 750 was also the I i-isopropyl glutaric anhydride; total 46.3 grams, 98% yield.

(0) Ethyl hydrogen-.i-isopropyl glutarate.This compound was prepared in the usual manner by alcoholysis of the anhydride. A 200 milliliter round bottom flask was equipped with reflux condenser, drying tube, and charged with 44.3 grams (0.284 mole) of the anhydride and 13.08 grams (0.284 mole) of anhydrous ethanol and brought to full reflux on the steam bath for one hour and allowed to stand overnight (15 hours). An infrared spectrum of this faintly colored solution indicated that the half-ester was present in high percentage. This reaction mixture was distilled under vacuum and 3 fractions were collected after a forerun of 1 milliliter of ethanol was distilled off. The tabulated data are below:

TABLE L-DISTILLATION OF ETHYLHYDROGEN-Zi-ISO- PROPYL GLUTARATE 3 4 1 gram of yellow pot residue was discarded; 87% yield and Dalta, J. Chem. Soc., 3195 (1951), in 50 milliliters of the title compound. of 95% ethanol was added 15 grams of potassium boro- (d) dl-3-is0pr0pyl-6-valer0lactone.A 3-neck, 1 liter hydride in small portions until the reaction ceased. The flask was set up on the steam bath and equipped with solution was refluxed for one hour, cooled, acidified with reflux condenser, drying tube and mechanical stirrer (all 5 sulfuric acid and extracted with ether. Concentraequipment thoroughly dried). The flask was charged with tion of the ether layer gave 5-hydroxy-2-isopropyl- 300 milliliters of tetrahydrofuran that had been freshly hexanoic acid as an almost colorless oil. This hydroxy distilled from calcium hydride and 45.7 grams (0.226 acid was heated on an oil bath at 180 for one hour and mole) of ethylhydrogen-3-isopropyl glutarate. To this distilled under reduced pressure; 7.2 grams of S-hydroxyvigorously stirred solution was added 24.4 grams (0.4-5 10 2-isopropylhexanoic acid, fi-lactone, boiling oint 112- mole) of potassium borohydride followed by 11 grams l 15/8 millimeters, were obtained. The lactone was of lithium chloride. This mixture was stirred at room identified from its infrared and nuclear magnetic resontemperature for 0.5 hour before turning the steam into ance spectra.

the bath. Upon heating a vigorous reaction with evolution Example IV of gas set in; the stirred mixture was kept at a gentle 15 reflux for 4.5 hours. After cooling to room temperature fiy is a commcrclaltly avallahlc the reaction was hydrolyzed in the usual manner with chfimiffll having formula dilute hydrochloric acid and thoroughly extracted with (3H ether. After drying the ether solution the ether was removed by distillation over a steam bath and the residue was transferred to a 100 milliliter distilling flask equipped with 15 centimeter Vigreaux column and fraction col- 0 lecter for distillation under reduced pressure. The results 0 are tabulated below: It is a water-White liquid, boiling point 100/ 10 milli- TABLE II.DISTILLATION OF 3-Is0PROPYL-s-VALEROLACTONE Fraction Vapor Pressure Weight (g.) Product Temp. (deg.)

1 85-89 800 18. 4 3-is0propyl-a-valerolactone (IR). 2 90-105 800 2. 28 Lactone+diol. 3 106 750 2. 55 3-isopropyl-1,5-pentanediol (IR).

1 A 7 gram residue of very viscous material was left in the distilling flask. It proved to be the diol contaminated with boric acid.

The tobacco additive dl-3-isopropyl-fi-valerolactone meters; infrared spertrum: 5:77 (vs), 7.95 (s), 8.15 (s), has the following structure: 9.20 (s); nuclear magnetic resonance spectrum: 7:8.92

C and and and 5.74 [(2)-CH O--]; C H O mass=1l4.

It has been found that the tobacco additives of the invention when incorporated into tobacco products impart a flavor and aroma both before and during smoking 0 0 which many smokers consider to be desirable in smoking It is a water-white liquid, boiling point 59/90,t, products. However, it is pointed out that the methods for 139/14 millimeters; infrared spectrum: 5.8 (vs), 7.95 fi g r characterizing the q y of a flavor 0r aroma (s), 8.2 (s) and 9.25 (vs) ,1.; nuclear magnetic resonance in the tobacco art are almost purely subjective and differspectrum: ent smokers may define the same flavor quite differently. Also, the compounds included within the broad scope of 908(6) (Spht 150p mp [(2) CH2 CO this invention may impart different flavors or aromas deand 5.77 [('2)CH O-];C H O mass=142. pending upon the alkyl substituents therein. Thus, the compounds comprehended by this invention, by subjective tests, impart characteristic flavors which are desirable in tobacco products and the smoke therefrom even though To a Sohlhoh 0f 1 g of fi'lsoplopyl'a'valerolactohe the exact character thereof cannot be described on the Example II.5-hydroxy-3-is0propyl-2-penrenoic acid, 6-lactone p f lf f according to the method of Example in 10 basis of known standards. The tobacco additive of Exammllhhters 0f h h feh'achlorlde Weft? added grams pic I imparts an :aroma and flavor which is reminiscent of of q and mhtture Was refluxed coconut which many smokers consider to be desirable in a hours hhdfir Irradlahon Wlth all Infrared heat P- tobacco product. The tobacco additive of Example II im- Filtration of the solution followed by concentration gave parts an aroma and flavor Which some characterize as a residue which was heated in an oil bath with 5 milliliters Coconut; the tobacco additive of Example III has a Spicy of dimethylaniline at for one hour. The solution was note; and that f Example IV has a spicy apple w diluted with 25 milliliters of water, extracted with ether, In accordance with this invention a compound and the ether lhyer W Washed With 100 milliliters of braced by generic formula I, or mixtures thereof, is added 5 N hydrochlorlc acld h concentfated- Vapor Phase 60 to tobacco or applied to a smoking article or its compochfhmatogl'aphy 0f the resldue gave mainly one subs/range nent parts in amounts of about 0.01 to 2.0 percent by Whlch Was Shown y Infrared and nuclear maghehc weight of the product. Preferably the amount of additive resonance p py to have The formula: is between about 0.1 and 0.5 percent by weight in order to H provide a tobacco product having a desired flavor and J aroma. However, the amount used will depend up n the amount of flavor and aroma desired and the particular compound or mixture thereof that is used. The additive may be incorporated at any step in the treatment of the O O tobacco but is preferably added after raging, curing and shredding and before the tobacco is formed into cigarettes.

Example y y' p y acid, Likewise, it will be apparent that only a portion of the Haclohe tobacco need be treated and the thus treated tobacco may To a l i of 163 grams f 5.k t 2.is0pr0py1- be blended with other tobaccos before the cigarettes or hexanoic acid, prepared by the method of Bardhan, De, other smoking articles are formed. In such case the t0- bacco treated may have the additive in excess of the amounts above indicated so that when blended with other tobaccos the final product will have the percentage within the indicated range.

In accordance with one specific embodiment of this invention, an aged, flue-cured and shredded tobacco is sprayed with a 1% ethyl alcohol solution of 3-isopropyl- B-valerolactone in an amount to provide a tobacco containing 0.2 percent by weight of the additive on a dry basis. Thereafter the alcohol is removed by evaporation and the tobacco is manufactured into cigarettes by the usual techniques. It has been found that the cigarette when prepared as indicated has a desired and pleasing flavor, an aroma which to some people is reminiscent of coconut and is detectable and pleasing in the main and side smoke streams when the cigarette is smoked.

'I he additives falling within the scope of this invention may be applied to the tobacco by spraying, dipping or otherwise, utilizing suitable suspensions or solutions of the additive. 'I'hus water or volatile organic solvents, such as alcohol, ether, acetone, volatile hydrocarbons and the like, may be used as the carrying medium for the additive while it is being applied to the tobacco. Also, other flavorand aroma-producing additives, such as those disclosed in United States Patents Nos. 2,766,145, 2,905,575, 2,905,- 576, 2,978,365 and 3,041,211 may be incorporated into the tobacco with the additive of this invention.

While this invention is principally useful in the manufacture of cigarette tobacco, it is also suitable for use in connection with the manufacture of pipe tobacco, cigars or other tobacco products. Furthermore, the compounds may be added to certain tobacco substitutes of natural or synthetic origin and by the term tobacco as used throughout this specification is meant anv composition intended for human consumption by smoking or otherwise, whether composed of tobacco plant parts or substitute materials or both.

Also, the invention has been particularly described with reference to the addition of the compounds directly to tobacco. However, it will be apparent that the compound may be applied to the paper of the cigarette or to the wrapper of a cigar. Also it may be incorporated into the filter tip, the packaging material or the seam paste employed for gluing the cigarette paper. Thus a tobacco product is provided which includes the specified additives and tobacco although in every instance the compound need not be admixed with the tobacco as above specifically described.

While several particular embodiments of this invention are shown above, it will be understood, of course, that the invention is not to be limited thereto, since many modifications may be made, and it is contemplated, therefore, by the appended claims, to cover any such modifications as fall within the true spirit and scope of this invention.

We claim:

1. A tobacco product having added thereto an amount suflicient to alter the flavor or aroma of the tobacco product of a compound selected from the group of compounds having the formula Formula I wherein R R and R are selected from the group consisting of hydrogen and alkyl groups with at least one of such substituents being alkyl.

2. A tobacco product having added thereto an amount sutficient to alter the flavor or aroma of the tobacco product of a compound selected from the group of compounds having the formula Formula persed therein a small amount sufiicient to improve the flavor thereof of 3-isopropyl-fi-valerolactone.

6. A tobacco product having added thereto and dispersed therein a small amount suflicient to improve the flavor thereof of 5-hydroxy-3-isopropyl-2-pentenoic acidfi-lactone.

7. A tobacco product having added thereto and dispersed therein a small amount suflicient to improve the flavor thereof of S-methyl-fi-valerolactone.

8. A tobacco product having added thereto and dispersed therein a small amount suflicient to improve the flavor thereof of 5-hydr0xy-2-isopropylhexanoic acid.

9. The product recited in claim 5 wherein the amount of flavorant is between about 0.01 and 2.0 percent by weight of said product.

10. The product recited in claim 6 wherein the amount of flavorant is between about 0.01 and 2.0 percent by weight of said product.

11. The product recited in claim 7 wherein the amount of flavorant is between about 0.01 and 2.0 percent by weight of said product.

12. The product recited in claim 8 wherein the amount of flavorant is between about 0.01 and 2.0 percent by weight of said product.

References Cited UNITED STATES PATENTS 2,766,149 10/1956 Rowland 13117 2,766,150 lO/1956 Teague 'l31-17 SAMUEL KOREN, Primary Examiner.

D. I DONOHUE, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No 3 ,380 ,457 April 30 1968 Joseph N. Schumacher et a1.

It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as show below:

Columns 3 and 4, TfBLE II, fourth column, line 3,

"2 .55" should read 2 ,55 Column 4 line 16 I'chemiral" should read chemical liI 1e 32,

'spertrum: 5 77" should read spectrum: 5.77

Column 6, line 14, "Formula" should read Formula I Signed and sealed this 7th day of October 1969.

(SEAL) Attest:

Edward M. Fletcher, Jr.

Attesting Officer Commissioner of Patents WILLIAM E. SCHUYLER, JR.

Claims (1)

1. A TOBACCO PRODUCT HAVING ADDED THERETO AN AMOUNT SUFFICIENT TO ALTER THE FLAVOR OR AROMA OF THE TOBACCO PRODUCT OF A COMPOUND SELECTED FROM THE GROUP OF COMPOUNDS HAVING THE FORMULA