JPS60100549A - Preparation of norbornadiene derivative - Google Patents

Abstract

PURPOSE:To obtain the titled compound useful as an agent to convert energy from easily obtainable raw materials in high yield, by reacting a cyclopentenone with a Grignard reagent, reacting the product with acetylenedicarboxylic acid diamide, dehydrating the resultant product. CONSTITUTION:A cyclopentenone shown by the formula I (R1-R4 are H, or lower alkyl, with the proviso that they are not H simultaneously; R5 is H, lower alkyl, lower alkenyl, or aryl) is reacted with a Grignard reagent shown by the formula R6MgX (R6 is lower alkyl, lower alkenyl, or aryl; X is halogen) at 10-150 deg.C. The reaction product is reacted with acetylenedicarboxylic acid diamide in a solvent such as dimethylformamide, etc. at 20-200 deg.C to give an amide shown by the formula II, which is dehydrated with a dehydrating agent such as thionyl chloride, etc. at -20-100 deg.C to give the desired substance shown by the formula III.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is based on the general formula (1) (wherein 1R, , R2, 3 and 4 represent a hydrogen atom or a lower alkyl group. No. Birds have hydrogen atoms, lower alkyl groups,
It represents a lower alkenyl group or an aryl group, and R6 represents a lower alkyl group, a lower alkenyl group, or an aryl group. ) The present invention relates to a method for producing a norbornagene derivative shown in the following.

The norbornadiene derivative represented by the above general formula (1) is known to exhibit extremely excellent effects as an energy conversion agent in a chemical conversion method for converting light energy into thermal energy, and its production method also includes: A method is known in which cyclobentenones are reacted with a Grignard reagent and then reacted with dicyanacetylene, or cyclopentadines are reacted with dicyanacetylene (Japanese Unexamined Patent Publication No. 149251/1982).
.

However, this method is disadvantageous as an industrial method because the raw material, dicyanacetylene, is unstable and difficult to obtain.

In addition, the following route is known as a method for synthesizing 2,8-dicyanonorbornadiene (Bull, Ohem,
8oc.

Jpn, ”, (1977) 50 2694]. This case is advantageous in terms of synthesis because dicyanacetylene is not used.

However, the present inventors applied the general formula (1) according to this method.
) In order to obtain a norbornagene derivative represented by the general formula (wherein 几1 #R1*R8I几, 几, and R
6 has the same meaning as above. ) Using the carboxylic acid esters shown as raw materials, amidation was attempted under general amidation conditions using an aqueous ammonia solution, liquid ammonia, etc., but no amidated product was produced, so it was not possible to obtain the target product. I couldn't do it either.

As a result of research on a new method for producing the norbornadiene derivative represented by the general formula (1), the present inventors found that the method is based on a new reaction route different from the conventional method, and is capable of solving the drawbacks of the conventional method. They solved the problem and found a method to obtain the target product in good yield, resulting in the present invention.

That is, the present invention converts cyclobentenones represented by the general formula (III) (wherein, R2, R3, R4 and R5 have the same meanings as above) into the general formula (IV) R,
After reacting with a Grignard reagent represented by MgX (in the formula, R6 has the same meaning as above and X represents a halogen atom), it was reacted with acetylene dicarboxylic acid diamide to obtain the general formula (1) (in the formula , Fan, , R2, R3, 几, , 几, and R6
has the same meaning as above. The present invention provides a method for producing a norbornadiene derivative represented by the general formula (1) by obtaining an amide represented by the formula (1) and then dehydrating it.

In the present invention, although a known method is known for the Grignard reaction, cyclobentenones are reacted with a Grignard reagent, then reacted with acetylene dicarboxylic acid diamide, and then dehydrated to obtain the desired norbornadiene derivative. This method was completely unknown until now, and was revealed for the first time by the present inventors.

The present invention will be explained in detail below.

The cyclobentenones represented by the general formula (I) used as raw materials in the present invention are easily available compounds (
JP-A-57-95985F), the conventionally known Grignard reaction is applied to the reaction between the cyclobentenones and the Grignard reagent, and the reaction conditions are not particularly limited. For example, both may be dissolved in advance in an organic solvent inert to the reaction such as ether, the Grignard reagent may be added to the cyclobentenone solution, and the mixture may be stirred at the required temperature, usually 10 to 150'C. Implemented by After the reaction is completed, hydrolysis is performed and the oil layer is concentrated to obtain a reaction product. Then, by reacting with acetylene dicarboxylic acid diamide, amides represented by general formula (1) are obtained.

The acetylene dicarboxylic acid diamide used here is, for example, the reaction of dimethyl acetylene dicarboxylate with an aqueous ammonia solution [Organic Synthetic Chemistry 28 485 (1965)]
can be easily obtained.

In this amidation reaction, the amount of acetylene dicarboxylic acid diamide used is arbitrary, at least 1 mole times the cyclobentenone represented by the general formula (IN) as the starting material, but preferably 1 to 1.5 moles. This is twice the range.

As the reaction solvent, amide compounds such as dimethylformamide, N,N-diethylformamide, N,N-dimethylacetamide, and hexamethylenephosphoramide are used.

The reaction temperature is usually arbitrary within the range of 20 to 200°C,
Preferably it is 50-170°C.

Note that during the reaction, the pH of the charging solution before the reaction affects the yield, and is usually pH 2 to 9 at room temperature, preferably pH 2 to 9 at room temperature.
It is carried out under a weakly acidic atmosphere of lI4-7. To create such a weakly acidic atmosphere, common acids such as hydrochloric acid, sulfuric acid, and p-)-luenesulfonic acid are used.

Amides represented by general formula (1) are produced in good yield from the reaction solution obtained in this way through operations such as concentration and crystallization, but it is not necessary to isolate the amides in order to carry out the dehydration reaction in the next step. Instead, the reaction mixture may proceed to the next step as it is.

In the dehydration reaction for obtaining the norbornadiene derivative represented by the general formula (1) from the amides represented by the general formula (1), thionyl halides such as thionyl chloride and thionyl bromide and phosgene are used as the dehydrating agent. The amount of the dehydrating agent to be used is arbitrary, at least 2 times the mole of the amide, but preferably in the range of 2 to 5 times the mole.

As the reaction solvent, the same amide compound used in the amidation reaction is used.

The reaction temperature is arbitrary within the range of -20 to 100°C,
Preferably it is -1θ to 60′C.

There is no particular restriction on the reaction time. After the reaction is completed, the reaction mixture is neutralized and subjected to common operations such as extraction, concentration, distillation, and crystallization to obtain the desired norbornadiene derivative in high yield.

The present invention will be explained below with reference to Examples.

Example 1 2.8- to 40 g of tetrahydrofuran under nitrogen atmosphere
Dimethyl-cyclopent-2-nin-1-one 11. O
g (0.1 mol), and a tetrahydrofuran solution (8.6 mol concentration) in which 0.13 mol of methylmagnesium chloride was dissolved was added dropwise at 10°C.
Continue stirring for hours.

The obtained reaction solution is added dropwise to cold water at lOoC, and after hydrolysis, NH, O/saturated aqueous solution is added and the organic layer is separated. The organic layer was dried with anhydrous sodium sulfate and concentrated to obtain a concentrated solution 14. O
get f.

Dimethylformamide 2009 was added to 14.0y of this concentrated solution.
and acetylene dicarboxylic acid diamide 18.4 g (0
.

After reacting for 4 hours at a reaction temperature of 110°C, the reaction solution was slightly concentrated to 200f.

In this reaction solution 200f, dimethylpolamide soy
and thionyl chloride 28.6! (0.24 mol) was added dropwise at 5°C, and stirring was continued for an additional hour.

The resulting reaction solution was poured into cold water, neutralized with alkali, extracted and separated into methyl isobutyl ketone for 10 minutes, and the resulting organic layer was concentrated and then subjected to simple distillation to obtain 2,3-dicyano-1,
5,6) 16.71 dimethylnorbornadiene was obtained.

Yield 96% m, p 72°C NMR (CDCe3) δrp 1.53 (S, 3H), 1.68 (s, 31 ()
, 1.80 (s, 3H), 2.16 (S, 2I ■), 3
．． 60 (s.

IH) Elemental analysis value (C, 2H1□N2) C% N% N% Theoretical value 78.28 6.57 15.21 Actual value 7
8.20 6.78 15.10 Example 2 2-allyl-8-methyl-cyclopent-2- in place of 2.8-dimethyl-cyclopent-2-en-1-one
The reaction was carried out in the same manner as in Example 1 except that en-1-one was used, and 2,8-dicyano-6-allyl-1,5-dimethylnorbornadiene was obtained in a yield of 75%.

b, p129-181 “C/ 21!!ItHgNM
R (CD30D) δ- 1,48 (s, 811), 1.80 (s, a■)
, 2.14 (s, 2H), 2.90 (d, 2fi), 8
．． 66(!'l.

lH), 4.80 (s, 2fI), 5.82-5.7
7 (m.

11M) Elemental analysis value (C1411,4N2) C% 11% N% Theoretical value 79,95 6.72 18.82 Actual value 7
9.32 6.81 18.85 Example 8 2-amyl-8-methyl-cyclopent-2-in place of 2.3-dimethyl-cyclopent-2-en-1-one
The reaction was carried out in the same manner as in Example 1 except that en-1-one was used, and 2,3-dicyano-6-amyl-1,5-dimethylnorbornadiene was obtained in a yield of 77%.

However, the final treatment after concentration was chromatographic separation.

NMm (ODC13) δP 0.70-0.150 (m, 9H), 1.55 (s, 8
H).

1.81 (s, 8H), 2.20 (3, 2H), 2.4
0 (Fl, 2H), 8.60 (IT, IH) Elemental analysis value (Ci6 20 Ng) C% N% N%

Claims (1)

[Claims] General formula (wherein R1, 几2.几, and R4 represent a hydrogen atom or a lower alkyl group. However, these are not hydrogen atoms at the same time. 几 is a hydrogen atom, lower alkyl group,
Indicates a lower alkenyl group or an aryl group. ) Cyclobentenones represented by the general formula (wherein, 几6
represents a lower alkyl group, a lower alkenyl group or an aryl group, and X represents a halogen atom. ) and then reacted with acetylenedicarboxylic acid cyanohydride to form a compound of the general formula (where TLl, R,, R3, R4, 几, and 几 have the same meanings as above) ), and then dehydrated to obtain an amide represented by the general formula (wherein, 几8.几, , R, , R4, AGE and TORI have the same meanings as above). A method for producing norbornagene derivatives as shown.