JPS625440B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to 2-stannylmethylbutadiene derivatives.

The present inventor previously proposed a 2-silylmethyl-1,3-butadiene derivative as a reagent for synthesizing a terpene compound (see Japanese Patent Application Laid-open No. 55-027162).

As a result of further research, the present inventor found that a 2-stannylmethyl-1,3-butadiene derivative containing tin instead of silicon is similarly useful as a reagent for synthesizing terpene compounds. It was discovered that isoprene units could be introduced, and the present invention was completed.

That is, the gist of the present invention is the general formula () (In the formula, R ¹ , R ² and R ³ represent an alkyl group.) 2-stannylmethyl-1,3-
Found in butadiene derivatives.

The present invention will be explained in detail below.

In the general formula (), R ¹ , R ² and R ³ are lower alkyl groups such as methyl, ethyl, propyl, butyl, octyl, etc., and these may be the same or different from each other. . Among these, those with less steric hindrance are preferred. Lower alkyl groups, especially methyl groups, are usually advantageous in preparation and use.

Some examples of the 2-stannylmethyl-1,3-butadiene derivatives according to the present invention include 2-trimethylstannylmethyl-1,3-butadiene,
Examples include 2-triethylstannylmethyl-1,3-butadiene.

The 2-stannylmethyl-1,3-butadiene derivative has the same meaning as chloroprene and the general formula () R ¹ R ² R ³ SnCH ₂ MgX () (wherein R ¹ , R ² and R ³ have the same meanings as in the general formula ()). (X represents a halogen atom.)
It can be produced by reacting with the stannylmethyl Grignard reagent shown below. As X, a chlorine atom is usually used, but a bromine atom or the like may also be used.

The reaction between chloroprene and stannylmethyl Grignard reagent is usually carried out in an inert solvent in the presence of a catalyst.

As the inert solvent, ether solvents such as ethyl ether are suitable.

As the catalyst, 1,3-bis(diphenylphosphinopropane) nickel chloride () is suitable.

Chloroprene is used in an equimolar amount relative to the stannyl methyl Grignard reagent, preferably 0.5 to 2 times.
Use twice the mole.

The amount of inert solvent used is about 0.5 to 5 per mole of stannyl methyl Grignard reagent.

The amount of catalyst used is about 1/1000 to 1/10 times the mole of the stannyl methyl Grignard reagent.

The reaction temperature of chloroprene and stannylmethyl Grignard reagent is usually -30 to 100°C, preferably 0 to 30°C.

The reaction time is about 1 to 100 hours.

After the reaction, the 2-stannylmethyl-1,3-butadiene derivative can be purified according to conventional organic chemistry methods, such as by appropriately combining solvent distillation, filtration, distillation, chromatography, activated carbon treatment, washing, etc. .

The obtained 2-stannylmethyl-1,3-butadiene derivative, like the 2-silylmethyl-1,3-butadiene derivative, is reacted with, for example, a carboxylic acid halide to form a 2-methylene- A ketone with a 3-butenyl group, i.e., an isoprene unit, was obtained, and upon reaction with an aldehyde, the carbonyl carbon of the aldehyde was changed to a 1-hydroxy-3-methylene-4-pentenyl group, i.e., an isoprene unit was also attached. The bound alcohol further
It is an extremely useful compound as a reagent for introducing isoprene units, as an addition product can be obtained by conducting a Diels-Alder reaction with a parent diene agent such as maleic anhydride under normal conditions.

EXAMPLES The present invention will be described in more detail with reference to Examples below, but the present invention is not limited in any way by the Examples unless the gist of the invention is exceeded.

Example: Magnesium 1.46 was placed in a 200ml three-necked flask equipped with a stirrer, dropping funnel and reflux condenser.
g (0.06 mol) and the inside was replaced with nitrogen gas. Next, 100 ml of ether was added, and 8.53 g (0.04 mol) of chloromethyltrimethylstannane was added dropwise to form trimethylstannylmethylmagnesium chloride. In a 500ml three-necked flask equipped with a stirrer, dropping funnel, and beaded condenser,
5.31 g (0.06 mol) of chloroprene and dichloro-
0.087 g (0.16 mmol) of 1,3-bis(diphenylphosphino)propane nickel was charged, the inside was purged with nitrogen gas, and the mixture was cooled to 0°C. Next, while stirring and maintaining the temperature at 0° C., the previously obtained reaction solution containing trimethylstannylmethylmagnesium chloride was added dropwise from the dropping funnel. After the dropwise addition was completed, the temperature was returned to room temperature, and the mixture was further heated and stirred under reflux for 3 hours. After the reaction was completed, the organic layer was extracted after hydrolysis. After drying the extract, the solvent was distilled off and further distilled under reduced pressure to obtain 2-trimethylstannylmethyl-
7.0 g (0.03 mol) of 1,3-butadiene was obtained.

Elemental analysis value C H Theoretical value (%) 41.61 6.98 (C ₈ H ₁₆ Sn) Actual value (%) 41.71 7.00 Boiling point 77-78℃/40mmHg nmr spectrum δ value (ppm) (CCl ₄ ) 0.07 (9H , S, Sn-CH ₃ ), 1.89 (2H, d, J
= 1.0Hz, Sn-CH ₂ ), 4.65-5.20 (4H, m, =
CH ₂ ), 6.33 (1H, d・d, J=10.0, 17.4
Hz, CH=CH ₂ ) IR spectrum (cm ^-1 ) (liquid film) 3080, 1625, 1590, 985, 960, 900 UV spectrum λmax (hexane) 239.5 nm (εmax1.0×
10 ⁴ ) The raw material chloromethyltrimethylstannane was produced by reacting chloro(chloromethyl)dimethylstannane synthesized from dichlorodimethylstannane and diazomethane with methylmagnesium bromide.

Claims (1)

[Claims] 1 General formula () 2-stannylmethyl-1,3 represented by (wherein R ¹ , R ² and R ³ represent a lower alkyl group)
-Butadiene derivatives.