JPS5877877A - Furan substitution product and its preparation - Google Patents

Abstract

NEW MATERIAL:A furan derivative of formulaI(R<1> and R<2> are 1-4C alkyl or R<1> and R<2> optionally may join through the O or N atom mutually and with the N atom form a 5-7 membered ring). EXAMPLE:2-Hexyl-5-dimethylaminomethylfuran. USE:An intermediate for preparing 2-hexyl-5-methylfuran which is a raw material for a perfume dihydrojasmone, medicines and agricultural chemicals and a synthetic intermediate for industrial chemicals. PROCESS:2-Hexylfuran, a secondary amine of formula II and formaldehyde are heated preferably in an aqueous solvent under refluxing to give the compound of formulaI. In the synthesis, the amounts of the secondary amine and the formaldehyde based on one mole 2-hexylfuran are as follows: usually 1-1.2mol, preferably one mole, secondary amine and usually 1-1.2mol, preferably one mole, formaldehyde. An aqueous solution of acetic acid is preferred for the aqueous solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a furan substituted product and a method for producing the same.

2-Hexydy-5-methylfuran is useful as a raw material for the fragrance Schichte O. Jasmone, and we 1. As a result of our research to find a new method for producing 2-hexyl-5-methylfurano, we created a M1-furan substituted product useful as an intermediate for the production of 2-hexyl-5-methylfuran, and arrived at the present invention. .

That is, the present invention is based on the general formula (wherein R'', H: are C1-4 furkyl groups, and Ji
It's ugly. ) and 2-hexylfurano (first invention) and the furano-substituted product represented by the general formula (in the formula, l (l, R2 is an alkyl group of C3 ~, and may be substituted) General formula (wherein R1, l (2 is R1 in general formula (2),
is the same group as R2] This is a method for producing a furan substituted product (second invention).

-ff In formula (1), the C2-4 alkyl group of R1 and R2 is a methyl group, an ethyl group, a 11- or a 1-
-furopyl group, n- or i-butyl group.

R1 and R2 are optionally oxygen atoms or divalent organic groups having 2 to 4 carbon atoms, which are interconnected via a nitrogen atom, such as -(CH2) n (n is 4 to 6), -OH, C
H, OCR, CH2-, -(J12Cl, NHCH2C
H,,- may be formed to form a 5- to 7-membered ring together with N, and examples of this cyclic group include a piperidino group, a morpholif group, and a piperazino group. Also R1,
Rj may be the same group or different groups.

Examples of the 7-run substituted product represented by the general formula fl), which is a novel compound of the present invention, include the following compounds.

(11,2-n-hexyl-5-dimethylaminomethylfuran (2), 2-n-hexyl-5-diethylaminomethylfuran (3), 2-n-hexyl-5-dimethylaminomethylfurano ( 41,2-n-hexyl-5-piperylenomethylfurano (5), 2-n-hexyl-5-bilzralenomethylfurano-1゜The furano substituted product represented by general formula (11 is 2- Hexylfurano and the general formula (in the formula, l(1,1lj2 is a C1-4 alkyl group, R1 and R2 are connected to each other via an oxygen atom or a nitrogen atom as the case may be) and may form a 5- to 7-membered ring) It can be synthesized by reacting a secondary amino represented by the following with formaldehyde.

Examples of the secondary amino represented by general formula (2) which is a reaction component include dimethylamine, diethylamine, dipropylamine, dimethylamine, morpholino, piperidine,
Examples include piperazine and their hydrochlorides.

Examples of formaldehyde include formaldehyde aqueous solution (88-17%). Equivalent substances that generate formal aldehyde, such as formal aldehyde, may also be used, but an aqueous solution of formal aldehyde is preferred.

In the synthesis, the secondary amine is usually used in an amount of 1 to 1.2 mol, preferably 1 mol, and the formaldehyde is usually used in an amount of 1 to 1.2 mol, preferably 1 mol, per 1 mol of 2-hexylfurano.

The reaction takes place in an aqueous medium. The aqueous medium is water and alcohol (methanol, ethanol, etc.),
Examples include aqueous solutions of ethers (tetrahydrofurano, dioxab, etc.), acetic acid and the like; of these, aqueous acetic acid is particularly preferred when used in combination with free secondary amines.

The furan-substituted compound of the present invention can be synthesized by heating and refluxing 2-hexylfuran, the secondary amine of general formula (2) or its hydrochloride, and formaldehyde in an aqueous medium. The reaction temperature is usually 50 to 120°C, preferably 90 to 110°C. The reaction time is usually 05-3
time, preferably 1 to 2 hours. The obtained crude reaction product is made alkaline, extracted with a solvent such as ether or toluene, washed with water, dried with Glauber's salt, etc., and then the solvent is distilled off to obtain a furano-substituted product.

The above reaction can be expressed as follows.

The structure of the furan-substituted product can be confirmed by infrared absorption spectrum and nuclear magnetic resonance absorption.

The furan-substituted product of the present invention is a raw material for the fragrance dihydrojasmone, a raw material for pharmaceuticals, agricultural chemicals, or a synthetic intermediate for industrial chemicals.
It is useful as an intermediate in the production of -hexyl-5-methylfuran. The method for synthesizing 2-hexyl-5-methylfuran using the furan substituted product of the present invention is as follows.

is a counter anion such as a halogen ion (CI, Br.

), alkyl sulfate anions, specifically R40SO, (R4 is C, ~4 alkyl group) and Eva CH3080, and arylsulfonate anions, specifically Ar80. (Ar is an aryl group or an alkylaryl group) For example, 06H380. ] Hereinafter, the present invention will be further explained with reference to Examples, but the present invention is not limited thereto.

Example 1 18 g of a 50% aqueous solution of dimethylamine is added to a mixture of 26 m/2-n-hexyl-5-dimethylaminomethylfuranacetic acid and 37% formalino 12j+/ while cooling. Next, 20 g of 2-n-hexylfurano is added and heated while stirring. When heated under reflux for about 1 hour, the initially colorless reaction solution gradually turns dark brown. After cooling, a solution consisting of 31 parts of sodium hydroxide and 100 parts of water is added to the reaction solution-3 while cooling. Most of the reaction products separate into the upper layer.

Add about 100 ml of ether and perform ether extraction. After drying the ether extract with potassium hydroxide and sodium sulfate,
Ether is distilled off and the residue is distilled to give 2-n-quinol-5-dimethylaminomethylfurano25. 'f (91
゜1%).

Boiling point 186-b Infrared absorption (IR) (Bim) 156G, 1470, 1450.1015.845°8
0 Nuclear magnetic resonance absorption (NMR) (CCI,) δppm0.9
0 (t, 3H, -C horse) 1.87 (m,
8H-CH2-)2.15 (s, 6HN-CI,
)2.56 (t, 2H=C-C112-)1 8.84 (s, 28N-C1l,
-)5.74-6.05((1,2H,-cH-CH-
) Example 2 6 liters of 2-n-hexyl-5-diethylfuranacetic acid, 2.7 ml of 87% formalin and 8.2 f of diethylamine were mixed under cooling, and then 2-11
- Add 4.6 f of hexylfuran and heat under reflux for about 2 hours.

A solution consisting of 7.5 g of sodium hydroxide and 25 Mt of water was added under cooling, and then treated in the same manner as in Example 1.
80.7 form).

Boiling point 82-b IR (dm) 1560, 1460, 1880, 1015.78
ONMR (CC14) δppII1 0.62-1.20 (m, 9H, -CH5) 1.8
6 (m, 1BH, -0H2-)2.28~2
．． 74 (m, 6H, N-CH2-C.

=C-CH2C) 8.58 (s, 211, N-CH2
-Cl) 5.72-5.96 (q, 2H, = ci
-i-cH-) Example 8 18 g of 2-n-hexyl-5-morpholinomethylfuranacetic acid, 6 ml of 87% formalin, and T ml of morpholine were mixed under cooling, and then 2-n-
Add hexylfuran 10F and heat to reflux for about 2 hours.

A solution consisting of sodium hydroxide IIV and 50 s+l of water is added under cooling. 15.5' of 2-n-hexyl-5-morpholinomethylfuran was obtained by ether extraction and vacuum distillation in the same manner as in Example 1. (98.1%)
get.

Boiling point 146-14τC/411HgIR (bim-1
) 1665.1455,1120,1010,870°8
O NMR (CC14) δppm 0192 (t, 8H, -CH,) 1.86
(m, sH, -CI(2,-)2.25~2
．． 75 (m, 6H,=9-CH,-, NCII,
-)8.40 (8,2H,NCH2C-)8
．． 49-8.75 (m, 4H, 0CH2-)5.
76-6.07 (q, 2i1. =CH-Cl1=
) Example 4 2-n-hexyl-5-piperazinomethylfuranacetic acid 6txt, 87% formalin 2.711/and piperidine 2.8f were mixed under cooling, and then L'te2
- Add 4.6 g of n-hexylfuran and heat under reflux for about 1.5 hours.

A solution consisting of 7.5 g of sodium hydroxide and 25 s of water was added under cooling, followed by the same treatment as in Example 1, followed by distillation under reduced pressure to obtain 6.7 f of 2-n-hexyl-5-piperidinomethylfuran ( 88.8%).

Boiling point 148-149/4smHg IR (9m) 1560.1470.11G5,1015,860,7
75NMR (CCI4) δppm' 0.91 (t, 8H, -CH,) 1.45
'(m, 12H, -CH2-)2.07~2.7
5 (m, 6H, N-CH2-, =9-[(2)8
．． 85 (8,2H,N-CH2-C= )5
．． 72-6.01 (q, 2H, =CH-CH= ) Example 5 2-n-hexyl-5-piperazinomethylfuranacetic acid 6m/, 87% formalin 2.7m/and piperazine hexahydrate 7f Mix while cooling (to form a colorless paste). Next, 4.6 g of 2-n-hexylfuran was added, and the mixture was heated under reflux for 2 hours. Sodium hydroxide 7.5g
A solution consisting of
Piperazinomethylfuran 5.8F (699%) is obtained.

Boiling point 122-124°C/8.5tyxHgIR (
am”)

Claims (1)

[Scope of Claims] (In the formula, R' and R2 are alkyl groups of 01 to ., and W
and 82 may be connected to each other via an oxygen atom or a nitrogen atom, as the case may be, to form a 5- to 7-membered ring together with 7N. ) is a furan substituted product. 2. The furan substituted product according to claim 1, which is 2-hexyl-5-dimethylaminomethylfuran. 8. The furan substituted product according to claim 1, which is 2-hexyl-5-diethylaminomethylfuran. 4. The furan substituted product according to claim 1, which is 2-hexyl-5-morpholinomethylfuran. The furan substituted product according to claim 1, which is 52-hexyl-5-piperidinomethylfuran. 6. The furan substituted product according to claim 1, which is 2-hexyl-5-piperazinomethylfuran. 7.2-Hexylfuran and the general formula (wherein, R' and R2 are C8-4 alkyl groups, and R
1 and 82 are optionally connected to each other via an oxygen atom or a nitrogen atom, and together with τN (this may form a 5-7 shell ring) a secondary amine or its hydrochloric acid represented by A general formula characterized by reacting a salt and formaldehyde [wherein R1 and R2 are Ill in general formula (2) f]
, R' is an upper-like group. ] A method for producing a furan-substituted product shown in the following. 8. The production method according to claim 7, wherein the reaction is carried out in an aqueous solvent. 9. The production method according to claim 8, wherein the aqueous solvent is an acetic acid aqueous solution.