JPS59137440A - Production of 2,3-dialkoxy-5-methyl-1,4-benzoquinone - Google Patents

Abstract

PURPOSE:The oxidation of a specific phenol is carried out by use of oxidative nitrogen oxide to enable rapid production of the titled substance, as a synthetic intermediate of coenzyme Q, by no use of organic solvents without contamination of metals, thus facilitating purification and waste disposal. CONSTITUTION:A phenol of formula I (R is lower alkyl such as methyl, ethyl or propyl; R' is lower alkyl such as methyl, ethyl or propyl, H) is oxidized with an oxidative nitrogen oxide such as N2O3, NO2, N2O4 or N2O5 to give a compound of formula II. In case of nitrogen dioxide, its amount is preferably 1-2 times the molar amount of the substrate. Further the reuse of the use gas is possible by introducing oxygen into the used gas.

Description

【発明の詳細な説明】 本発明は、下記ａＤ式で示される２、３−ジアルコキシ
−５−メチル−１，４−ベンゾキノンの製造法に関する
ものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing 2,3-dialkoxy-5-methyl-1,4-benzoquinone represented by the following formula aD.

（但［７、式中Ｒはメチル、エチル、プロピル等の低級
アルキル基であυ、Ｒ′（ハメチル、エチル。(However, [7, in the formula, R is a lower alkyl group such as methyl, ethyl, propyl, etc. υ, R' (hamethyl, ethyl.

プロピル等の低級アルキル基、及び水素である。）■式
中ＩＬがメチル基である２、３−ジメトキシ−５−メチ
ル−１，４−ベンゾキノンは、補酵素Ｑ合成の中間体と
して極めて有用な化合物である。These are lower alkyl groups such as propyl, and hydrogen. ) 2,3-dimethoxy-5-methyl-1,4-benzoquinone in which IL is a methyl group is an extremely useful compound as an intermediate for coenzyme Q synthesis.

本発明は、（１）式で示される２、３．４−　トＩＪア
ルコキシ−６−メチルフェノール、及び２．３−ジアル
コキシ−５−メチル−１，４−ハイドロキノンを、０式
で示２れる２、３−ジアルコキシ−５−メチル−１６４
−ベンゾキノンに酸化するに当たって、酸化能を持つ窒
素酸化物（Ｎ、、Ｏ，、Ｎｏ、、　、　Ｎ２Ｏ４，Ｎ２
０゜等）を用いる事を・特徴としており、従来用いられ
ている一般的酸化剤である金属酸化物（例えば、塩化第
二鉄、二酸化マンガン、酸化銀、二酸化鉛等）を用いる
既知の方法に比較して、金属等の混入がない事、有機溶
剤を用いないでも反応が進む事、気体と液及び固体との
反応である事などにより、精製が容易であわ、廃棄物処
理が容易である事、さらに、反応が速く、定力ｌ−的に
進む事など、多くの利点を有し７ている。The present invention provides 2,3,4-toIJ alkoxy-6-methylphenol represented by formula (1) and 2,3-dialkoxy-5-methyl-1,4-hydroquinone represented by formula 0. 2,3-dialkoxy-5-methyl-164
- When oxidizing to benzoquinone, nitrogen oxides with oxidizing ability (N, , O, , No, , N2O4, N2
This is a known method that uses a metal oxide (e.g., ferric chloride, manganese dioxide, silver oxide, lead dioxide, etc.), which is a conventionally used general oxidizing agent. Compared to conventional methods, it is easier to purify and dispose of waste because there is no contamination with metals, etc., the reaction proceeds without the use of organic solvents, and the reaction is between gas, liquid, and solid. Furthermore, it has many advantages, such as rapid reaction and constant force l-like behavior.

紮素酸化物は、二酸化窒素の場合、基質に対し１〜２倍
モル使用するのが適当であり、大過剰に用いると副反応
が起り好ましく々い。捷だ反応後のカスに酸素を導入し
再循環使用も可能である。In the case of nitrogen dioxide, it is appropriate to use 1 to 2 times the mole of the ligation oxide relative to the substrate, and if it is used in large excess, side reactions will occur, which is preferable. It is also possible to introduce oxygen into the residue after the shredding reaction and recycle it.

実施例■では反応が定量的に進む事により、生成物を副
生するメタノール等の物勾を減圧で除去するのみで得る
事が出来る。以下に実施例を示す。In Example 2, the reaction progresses quantitatively, so that the product can be obtained simply by removing by-produced substances such as methanol under reduced pressure. Examples are shown below.

実施例■ （ ２，３４−トリメトキシ−６−メチルフェノール０．４
４０ｇを二酸化窒素ガス７５ｍ１ｊ入ｆ１だフラスコ内
に導入し、室温で３０分間反応させる。反応後副生ずる
メタノール及びガス等を減圧で除去すると、生成物０．
４０２９（収率９９％）が得られる６、生成物はガスク
ロマトグラフィーを用いた内部標準法による定量で、１
００％純度であり、融点５７〜５８°Ｃの赤色結晶であ
る。その赤外線吸収スペクトル及び、核磁気共鳴スペク
トルは、標品である２３−ジメトキシ−５−メチル−１
，４−ベンゾキノンと一致した。Example ■ (2,34-trimethoxy-6-methylphenol 0.4
40 g of nitrogen dioxide gas was introduced into a flask containing 75 ml of nitrogen dioxide gas, and the mixture was allowed to react at room temperature for 30 minutes. After the reaction, methanol and gas produced as by-products are removed under reduced pressure, resulting in 0.0% product.
4029 (yield 99%)6, the product was quantified by the internal standard method using gas chromatography, and the product was 1
00% pure, red crystals with a melting point of 57-58°C. The infrared absorption spectrum and nuclear magnetic resonance spectrum of the standard product 23-dimethoxy-5-methyl-1
, 4-benzoquinone.

実施例ＴＩ ２．３−ジメトキシ−５−メチル−１，４−ハイドロキ
ノン０．４００９を実施例Ｉと同様に７５ｍ１ｌり二酸
化僚素カスと反応させる。反応後トルエン；ｉｉ出１７
．５％炭酸水素ナトリウム水溶液、水で洗浄する。無水
硫酸ナトリウムで乾燥後、溶媒を減圧で除去すると、２
．３−ジメトキシ−５−メチル−１，４−ベンゾギ１．
ノンの赤色結晶０．３５０．＠（収率８８％）が得られ
る　生成物の赤外線吸収スペクトル、核磁気共鳴スペク
トルは標品と一致した。Example TI 0.4009 g of 2.3-dimethoxy-5-methyl-1,4-hydroquinone is reacted as in Example I with 75 ml of chlorine dioxide scum. Toluene after reaction; ii Ex 17
．． Wash with 5% aqueous sodium bicarbonate solution and water. After drying over anhydrous sodium sulfate and removing the solvent under reduced pressure, 2
．． 3-dimethoxy-5-methyl-1,4-benzogy1.
Non red crystal 0.350. The infrared absorption spectrum and nuclear magnetic resonance spectrum of the product were consistent with the standard product.

日本パーオキサイド株式会社Nippon Peroxide Co., Ltd.

Claims (1)

【特許請求の範囲】[Claims] （１）式に示されるフェノール類を、酸化能を持つ窒素
酸化物（Ｎ２Ｏ３，ＮＯ，、、Ｎ、Ｏ２，Ｎ、０．等）
を用い酸化する事を特徴とする２、３−ジアルコキシ−
５−メチル−１，４−ベンゾキノン（０式）の製造法。 （但し２、式中Ｉ（はメチル、エチル、プロピル等の低
級アルキル基でアシ、Ｒ′ハメチル、エチル。 プロピル等の低級アルキル基、及び水素である。）(1) Nitrogen oxides (N2O3, NO, , N, O2, N, 0., etc.) that have the ability to oxidize the phenols shown in formula
2,3-dialkoxy-, which is characterized by being oxidized using
Method for producing 5-methyl-1,4-benzoquinone (formula 0). (However, 2, in the formula I (I) is a lower alkyl group such as methyl, ethyl, propyl, etc., R' hamethyl, ethyl, a lower alkyl group such as propyl, and hydrogen.)