DE1072629B - Process for the preparation of dihydrofuranone derivatives - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

kl. 12 q 24

INTERNAT. KL. C 07 d

PATENT OFFICE

EXPLAINING EDITORIAL 1072 629

U 5550 IVb / 12 q

REGISTRATION DATE: AUGUST 19, 1958

NOTICE
DEK REGISTRATION
AND ISSUE OF THE
EDITORIAL:

JANUARY 7, 1960

The invention relates to the preparation of dihydrofuranone derivatives which are used as antioxidants, sequestering agents can be used for heavy metal ions and flavorings.

According to the invention, 3,4,5-trialkyl-5-oxy-2,5-dihydrofuranone- (2) and 3,4-dialkyl-5-alkylidene-2,5-dihydrofuranone- (2) of the general formulas

R ₁ R ₂

R ₁ R ₂

respectively.

O = C

c:

OH

O = C ^ C = R ₄

manufactured. In this formula, R ₁ and R ₂ denote hydrogen atoms or straight or branched chain alkyl groups with 1 to 5 carbon atoms, with the proviso that at least one of the two symbols represents such an alkyl group. R ₃ denotes a saturated or unsaturated hydrocarbon radical with 2 to 7 carbon atoms in a straight chain and a total of 2 to 9 carbon atoms, the hydrocarbon radical having a branched or straight aliphatic chain or a cycloaliphatic, aliphatic-cycloaliphatic or aliphatic-aromatic group. Here, a cycloaliphatic or aromatic ring of η carbon atoms is counted as η -2 carbon atoms to determine the length of the straight chain. R ₄ denotes a group which differs from R ₃ only in that it contains 1 less hydrogen atom on the first carbon atom and is bonded to the furan ring with a double bond. These compounds are prepared by using a substituted maleic anhydride of the formula

, 0 Process for the preparation of dihydrofuranone derivatives

Applicant: Unilever N.V., Rotterdam (Netherlands)

Representative: Dr. E. Wiegand, Munich 15,

and Dipl.-Ing. W. Niemann, Hamburg 1, Ballindamm 26,

Patent attorneys

Claimed Priority: Great Britain August 19, 1957

Jan Boldingh, Viaardingen (Netherlands),

Guido Lardelli, crossroads, Lake Constance (Switzerland), Pieter Roele, Greult Dijkstra, Viaardingen, Pauline Haverkamp Begemann, Dordrecht,

Pieter Daniel Harkes and Anthonie Simon Maria van der Zijden,

Vlaardingen (Netherlands) have been named as the inventor

is a free radical which contains a metal and a halogen atom or a further group R ₃ . The compounds obtained in this way are then hydrolyzed and, if appropriate, water is also split off.

R ₃ can e.g. B. represent one of the following groups:

Rp ρ

;O

R ₂ -CC:

with an organometallic compound R ₃ X to form a compound of the formula g - CH ₃ —CJEIgCH ₂ CH ₃ —CH ₂ (CH ₂ J ₂ CH ₃ CH ₈ (CHg) ₈ CH, —CH ₂ (CH ₂ ) ₄ CH ₃ - CH ₂ (CH ₂ ) ₅ CH ₃ .CH ₃ .CH ₂ CH ₃

Ri

C = O = C

R ₂

—CH;

—Ofio C Ho C χι

Δ Δ

CH ₂ CH ₃

/ CH ₃
^S CH,

Cxi 3

, C H2 ■ - C H2

-CH

C H2 - C H2

CH ₂ - CH ₂

ox p-pr pxj

converts, where X is replaced by a hydrogen atom-909 708/327

-CH ₂ -CH = CH-CHv

-CH ₉

The oxy-dihydrofuranones can be prepared according to the invention, for example, in the following way:

a) A suitable alkyl substituted maleic anhydride is left react with an alkyl magnesium halide and hydrolyze the reaction product:

R ₁ -CC

ll

R ₂ -CC

+ R ₃ MgCl

R ₁ -CC

OMgCl

r, —c — c:

R =,

The reaction is to be carried out at a temperature below ⁰ ° C., preferably at −70 ° C. or lower, in order to avoid that the magnesium compound obtained in the first stage reacts further with one or more molecules of the alkyne magnesium halide.

b) An alkyl-substituted maleic anhydride is left react with an alkyl zinc halide or preferably a dialkyl cadmium and hydrolyze the Reaction product:

R ₁ - C - C. R ₁ - C - C ^

I / ⁰ + ^R 3 ^CdR 3 »I

Rp C "R Γ C

R _x -C- <

R ₂ -c-c;

-, ο

, 0

^ OCdR ₃

The dihydrofuranones can be prepared according to the invention by treating the corresponding oxydihydrofuranone with a suitable dehydrating agent, e.g. B. a mixture of acetic anhydride, glacial acetic acid and concentrated sulfuric acid, according to the following reaction scheme, in which R ₃ 'represents an R ₃ group without the first CH ₂ group:

prevent the development of undesirable odors caused by oxidation or bacteria or delay.

The dihydrofuranones obtained according to the invention in which R _{4 is} a mixed aliphatic-aromatic group, e.g. B. the compounds of the formulas

CH.

, 0

R ₁ -CC

R ₂ -CC '-H ₂ O

ί OH
C.

R ₁ -CC:

R ₂ -CC

CH

40

45 O = CC = CH-CH

CH ₃ CH ₃

The alkyl-substituted maleic anhydrides used as starting materials can be prepared according to known methods Methods are obtained.

The dihydrofuranones obtained according to the invention, in which R _{4 represents} an aliphatic, cycloaliphatic or mixed cycloaliphatic group, have an odor reminiscent of celery. They are particularly suitable for improving the properties and, in particular, the aroma of margarine and other foods consisting of or containing fat.

To give margarine a flavor with the help of these dihydrofuranones, 1 part by weight is sufficient in some cases per 1 million parts by weight of margarine, while in other cases up to 100 parts by weight per million are required could be.

The dihydrofuranones described give margarine typical individual flavors or develop them in your; However, all of these flavors are reminiscent of butter and are largely similar to each other.

The dihydrofuranones not only improve the flavor of margarine and other fatty foods, they also increase their shelf life by making them O = C

= CH-CH = CH-

have a scent reminiscent of violets, lilacs and balsam. The oxy-dihydrofuranones described can be used as emulsifiers. In addition, they can be used ^{successfully as thickeners at temperatures between 0} ° C. and room temperature.

The invention is explained in more detail by means of the following examples.

example 1

This example relates to the production of the 3,4-dimen-

thyl-5-oxy-5-alkyl-2,5-dihydrofuranone- (2) in which the 5-alkyl group is a saturated straight chain group and the corresponding S ^ dimethyl-S-alkylidene-2,5-dihydrofuranone- (2).

The starting materials used were 2,3-dimethyl maleic anhydride and an n-alkyl magnesium bromide in which the alkyl group is selected from ethyl, n-propyl or one higher homologous group until n-heptyl existed.

150 ecm of a solution of n-Alkyhnagnesiumbromids in ether, which contained 0.15 mol of the bromide and had a temperature of about 20 ⁰ C, were in I ¹ Z ₂ hours to a solution of 0.13 mol of 2,3-dimethyl maleic anhydride in 150 cc of toluene were added, which was maintained at -70 ⁰ C. This temperature was maintained for 1 hour, after which it was up to - 10 ⁰ C rise

rbind
'V
R = Tabel I. 1.5252
1.5226
1.5176
1.5103
1.5082
1.5071 UV
Maximum in
Petroleum ether Ve
H ₃ C
R = Bp ° C / mm 270
270 C ₂ H ₄
C ₃ H ₆
C ₄ H ₈
C ₅ H ₁₀
CeH ₁₂
C ₇ H ₁₄ ung
/ CH ₃ 58 / 0.35
55 / 0.15
68 / 0.2
123 / 0.5
108 / 0.2
93 / 0.1 1.4734
1.4730
1.4719
1.4711 270 Ve
H ₃ C _x
R ₇
OH Bp ° C / mm 270
270
270 C ₂ H ₈
C ₃ H ₇
G ₄ H ₉
C ₅ H ₁₁
CeH ₁₃
^C 7H ₁₅ 112 / 0.5
114 / 0.2
132 / 0.2
134 / 0.2
145 / 0.2
155 / 0.2 UV
Maximum in
Petroleum ether 213
214
214
213
211
215 binding
/ CH ₃
^X O '
R =

let. At this temperature, 100 ecm of a 20% strength aqueous ammonium chloride solution were added. Two layers formed, one aqueous layer that was washed out once with a small amount of toluene and a toluene layer to which the toluene used for washing the aqueous layer was added became. The toluene fraction was dried over anhydrous sodium sulfate. After distilling off the Solvent in a vacuum of about 30 mm Hg

ίο became the crude oxy-dihydrofuranone obtained in this way fractionated in a vacuum. The pure oxy-dihydrofuranone, which is obtained in an amount of about 0.1 mol was elicited by handling with a mixture of acetic anhydride, glacial acetic acid and concentrated sulfuric acid converted into the corresponding dihydrofuranone. The dihydrofuranone was extracted with petroleum ether, the petroleum ether solution was washed until it had a neutral reaction, the petroleum ether was distilled off and finally the dihydrofuranone is distilled in vacuo.

The physical characteristics of the pure oxydihydrofuranones and dihydrofuranones are given in Table I. compiled.

Example 2

This example illustrates the preparation of the 3,4-dimethyl-5-oxy-5-alkyl-2,5-dihydrofuranone- (2), in which the 5-alkyl group is a branched acyclic group or a cycloaliphatic group, and the corresponding 3,4-dimethyl-5-alkylidene-2,5-dihydrofura- none- (2).

The starting materials were 2,3-dimethyl maleic anhydride and an alkyl magnesium bromide, in which the alkyl group consists of l'-ethylpropyl, 3'-methylbutyl, Cyclohexyl or methylcyclohexyl consisted. The production was carried out according to Example 1.

The physical constants of the pure oxydihydrofuranones and dihydrofuranones are given in Table II compiled.

Table II

Verbinc
H ₃ C _x Bp ° C / mm F. ° C »Ff UV maximum
in petroleum ether lung
/ CH ₃
= O R = 72 / 0.15 - 1.5098 270 H ₃ C.
χ CH - CH ₂ - CH =
H ₈ C ^κ 84 / 0.2 - 1.5350 282 H ₃ C - CH ₂ .
H ₃ C-CH ₂ - 73 - 282 / CH ₂ -CH ₂ .
H ₂ C. .C; =
CH ₂ - CH ₂ - 76 - 273 , CH ₂ - CH ₂ .
H ₂ C., CH - · CH ==
CH ₂ - CH ₂

7th H ₃ C,
\ , CH - CH ₂ - CH ₂ - '^ CH- H ₃ C-CH ₂ Bp ° C / mm F. ⁰ C 8th «Ff UV maximum
in petroleum ether link H ₃ C-CH ₂ , Λττ PTT
y * - '-tiβ * -' * ^ * 2 N.
χι r- ^/ P XT H ₃ C CH ₃ CH ₂ - CH ₂ ^ß / o ^U
OH PTT P TT
^ U JtI ₂ - OxI ₂ ^ 120 / 0.2 - 1.4721 213 R = H ₂ C ^ .CH-CH ₂ -
'P TT Γ TI
LxXl ₂ VXx ₂ - 69 - 208 158.5 214 140 / 0.06 67 - 216

Example 3 ₃₀ Example 4

This example illustrates the preparation of the 3,4-di- This example illustrates the preparation of the 3,4-diethyl

methyl-5-oxy-5-aralkyl-2,5-dihydrofuranone- (2) and the 5-oxy-5-alkyl-2,5-dihydrofuranone- (2) and 3,4-diethyl

corresponding 3,4-dimethyl-5-araU £ yl-2,5-d ^ nydrofura-5-alkylidene-2,5-dihydrofuranone- (2).

none- (2). The starting materials used were 2,3-diethyl

The starting materials were 2,3-dimethyl maleic anhydride and an n-alkyl magnesium bromide,

anhydride, ß-Phenyläthylmagnesiumbromid and phenyl in which the alkyl group from η-butyl, n-pentyl or methyl magnesium bromide used. The production er-n-hexyl constituents. Production took place according to the example.

followed according to example 1. The physical characteristics of the pure oxy-

The physical parameters of the pure oxydihydrofuranones and the pure dihydrofuranones are in

dihydrofuranones and dihydrofuranones are shown in Table III 40 Table IV.

listed. Table IV

Table III

■ connection ί
0 CH ₃ F. ⁰ C UV
Maximum in
Petroleum ether H ₃ C _x _y 0 f Vh ₂ C-HC = I 0 CH ₃ 36.5 274 H ₃ C _x 0 <"VchJ I.
Ό CH ₃ 119 322 H ₃ C, 0 J-CH ₂ -CH ₂ - / 92.5 216 OH i
0 CH ₃ H ₃ C _x 0 <-CH ₂ ^
^V 'OH 76 217

link
C ₂ H ₅ C ₂ H ₅

R =

R =

/ = O

C ₄ H ₈

55 connection

CrtHt; C _n H

R7! , = O

60 OH

R =

C ₄ H ₉

C ₆ H ₁₃

Bp ° C / mm

69 to 74 / 0.1

78 to 85 / 0.06

105 to 113 / 0.1

Bp ° C / mm

114 to 115 / 0.065
114 to 115 / 0.065

to 0.045
123 to 124 / 0.061

1.5032

1.4722
1.4720

1.4717

UV maximum in petroleum ether

270 270 270

UV maximum in petroleum ether

210 218

218

Example 5

This example relates to the preparation of a mixture 70 of 3- and 4-methyl-5-oxy-5-pentyl-2,5-dihydrofuranone- (2)

and a mixture of 3- and 4-methyl-5-pentylidene-2,5-dihydrofuranone- (2).

Methyl maleic anhydride and n-pentyl magnesium bromide were used as starting materials. the Production took place according to Example 1.

The physical characteristics of the process products are given in Table V.

Table V

Mix of
links
from TJ C
H ₁₁ C ₅ /
OH Q H ₃ C CH ₃ and
CH ₃
\ _ J Bp ° C / mm 1.4818 UV
maximum
in
Petrol
ether CH ₃ other -Π-0 H ₁₀ C ₅ = = 0 ¹¹ o? ⁰ . 126 / 0.22 211 - 100 to 110 / 0.2 273

10

Example 6

35

40

This example illustrates the preparation of 3,4-dibutyl-S-oxy-5-pentyl-2,5-dihydrofuranone- (2) and 3,4-dibutyl-5-pentylidene-2,5-dihydrofuranone- (2).

The starting materials were 2,3-dibutyl maleic anhydride and n-pentyl magnesium bromide are used. The production was carried out according to Example 1.

The physical characteristics of the pure process products are included in Table VI.

50 Table VI

55

link V C ₄ Η » Kp. ° C / mm »1 ° C ₄ H ₉ C ₄
\ / V = 0 H ₉ H ₁₁ C5-7
OH
C ₄ H ₉ 150 to 155 / 0.2 1.4690 H ₁₀ C ₅ = 125 to 128 / 0.2 1.4874

60

Claims (3)

Patent claims: 1. Process for the preparation of dihydrofuranone derivatives of the general formulas R ₁ R ₂
C == C
O = C c { , R ₃ respectively. R ₁ R ₂ O = CC = R ₄ in which R ₁ and R _{2 are} hydrogen atoms or alkyl groups with a straight or branched chain with 1 to 5 carbon atoms, at least one such alkyl group must be present, R _{3 is} a saturated or unsaturated hydrocarbon radical with 2 to 7 carbon atoms in a straight chain and a total of 2 to 9 denotes carbon atoms, where this radical can have a branched or straight aliphatic chain or consist of a cycloaliphatic, aliphatic-cycloaliphatic or aliphatic-aromatic group and a cycloaliphatic or aromatic ring of η carbon atoms is counted as a chain of η -2 carbon atoms, R ₄ denotes a group which differs from R ₃ only in that it contains 1 less hydrogen atom on the first carbon atom and is bonded to the furan ring with a double bond, characterized in that substituted maleic anhydrides of the formula , 0 R ₁ -CC: R ₂ -CC with organometallic compounds R ₃ X to form compounds of the formula f f C-C O = C reacted, where X is a radical which can be replaced by a hydrogen atom and which contains a metal and a halogen atom or a further group R ₃ , hydrolyzes the compounds obtained and, if appropriate, splits off water from them. 2. The method according to claim 1, characterized in that compounds R ₃ X are used which contain magnesium, zinc or cadmium as the metal atom. 3. The method according to claim 2, characterized in that as R ₃ X is a magnesium Grignard reagent used and the reaction at a temperature below 0 ⁰ C, preferably at -70 ⁰ C or lower, is carried out. © 909 708/327 12.59