JP3543408B2 - Method for producing α-ketone acid ester - Google Patents

Description

（式中、Ｒ¹ は水素原子、又は炭素数１〜６の脂肪族低級アルキル基、フェニル基及びベンジル基から選ばれる置換基を、Ｒ² は炭素数１〜６の脂肪族低級アルキル基を示す）
【０００９】
具体的には、グリコール酸メチル、グリコール酸エチル、グリコール酸ｎ−プロピル、グリコール酸ｉ−プロピル、グリコール酸ｎ−ブチル、グリコール酸ｎ−ペンチル、グリコール酸ｎ−ヘキシル等のグリコール酸エステル、乳酸メチル、乳酸エチル、乳酸ｎ−プロピル、乳酸ｉ−プロピル、乳酸ｎ−ブチル、乳酸ｎ−ペンチル、乳酸ｎ−ヘキシル等の乳酸エステル、マンデル酸メチル、マンデル酸エチル、マンデル酸ｎ−プロピル、マンデル酸ｉ−プロピル、マンデル酸ｎ−ブチル、マンデル酸ｎ−ペンチル、マンデル酸ｎ−ヘキシル等のマンデル酸エステル、α−ヒドロキシ桂皮酸メチル、α−ヒドロキシ桂皮酸エチル、α−ヒドロキシ桂皮酸ｎ−プロピル、α−ヒドロキシ桂皮酸ｉ−プロピル、α−ヒドロキシ桂皮酸ｎ−ブチル、α−ヒドロキシ桂皮酸ｎ−ブチル、α−ヒドロキシ桂皮酸ｎ−ペンチル、α−ヒドロキシ桂皮酸ｎ−ヘキシル等のα−ヒドロキシ桂皮酸エステルなどを挙げることができる。
【００１０】
そして、本発明で得られるα−ケトン酸エステルは、次の一般式（II）で示される化合物である。
【化２】

（式中、Ｒ¹ は水素原子、又は炭素数１〜６の脂肪族低級アルキル基、フェニル基及びベンジル基から選ばれる置換基を、Ｒ² は炭素数１〜６の脂肪族低級アルキル基を示す）
【００１１】
具体的には、グリオキシル酸メチル、グリオキシル酸エチル、グリオキシル酸ｎ−プロピル、グリオキシル酸ｉ−プロピル、グリオキシル酸ｎ−ブチル、グリオキシル酸ｎ−ペンチル、グリオキシル酸ｎ−ヘキシル等のグリオキシル酸エステル、ピルビン酸メチル、ピルビン酸エチル、ピルビン酸ｎ−プロピル、ピルビン酸ｉ−プロピル、ピルビン酸ｎ−ブチル、ピルビン酸ｎ−ペンチル、ピルビン酸ｎ−ヘキシル等のピルビン酸エステル、フェニルグリオキシル酸メチル、フェニルグリオキシル酸エチル、フェニルグリオキシル酸ｎ−プロピル、フェニルグリオキシル酸ｉ−プロピル、フェニルグリオキシル酸ｎ−ブチル、フェニルグリオキシル酸ｎ−ペンチル、フェニルグリオキシル酸ｎ−ヘキシル等のフェニルグリオキシル酸エステル、フェニルピルビン酸メチル、フェニルピルビン酸エチル、フェニルピルビン酸ｎ−プロピル、フェニルピルビン酸ｉ−プロピル、フェニルピルビン酸ｎ−ブチル、フェニルピルビン酸ｎ−ペンチル、フェニルピルビン酸ｎ−ヘキシル等のフェニルピルビン酸エステルなどを挙げることができる。
【００１２】
本発明で使用される分子状酸素としては一般的には空気が用いられるが、更に窒素、アルゴン等の不活性ガスで希釈された空気又は酸素ガスを用いてもよい。このとき、空気又は酸素ガスは、酸素に対する不活性ガスのモル比が通常２〜５０、好ましくは４〜３０であるように希釈される。
【００１３】
本発明で使用される触媒としては、リン酸銅が担体に担持された触媒が用いられるが、リン酸銅は担体に対して銅原子換算で通常１〜２０重量％、特に２〜１５重量％担持されていることが好ましい。
【００１４】
本発明で使用される担体としては、例えば、炭化ケイ素、α−アルミナ、酸化ジルコニウム、酸化チタン、シリカアルミナが挙げられ、中でも炭化ケイ素、α−アルミナが好適に挙げられる。そして、更に好適にはシリカ含有量が３０重量％以下、特に２５重量％以下の炭化ケイ素、α−アルミナが使用される。ＢＥＴ法で測定される担体の比表面積は、通常０．０１〜２０ｍ² ／ｇ、特に０．０２〜１０ｍ² ／ｇ程度であることが好ましい。また、担体の粒径は通常１〜２０ｍｍ、特に１〜１０ｍｍ程度であることが好ましい。
【００１５】
前記触媒においては、銅以外の他の金属がリン酸塩、酸化物、金属等のいずれかの形態で担持されていても差し支えない。他の金属としては、例えば、リチウム、カリウム等のアルカリ金属、マグネシウム、カルシウム等のアルカリ土類金属、ランタン、セリウム等のランタニド金属、及びモリブデン、スズ、マンガン、ビスマス、コバルト、銀、鉛、アンチモン、鉄が挙げられるが、これらの金属は、それぞれ単独又は複数で銅に対する原子比（他の金属／銅）が通常２．０未満の割合で担体に担持されていることが好ましい。
【００１６】
前記触媒の調製法は、担体にリン酸銅が担持されていれば特に限定されるものではなく、含浸法、蒸発乾固法など公知の方法を用いることができる。例えば、銅及び必要に応じてその他の金属の塩を水に溶解させ、これに化学量論量のリン酸を加えた溶液を前記担体に含浸後、空気中１１０℃付近で乾燥し、更に空気中４００〜９００℃で焼成する方法により調製することができる。
なお、銅及びその他の金属の塩としては、硝酸第二銅、硫酸銅、塩化第二銅等の銅の塩、及びリチウム、カリウム等のアルカリ金属、マグネシウム、カルシウム等のアルカリ土類金属、ランタン、セリウム等のランタニド金属、モリブデン、スズ、マンガン、ビスマス、コバルト、銀、鉛、アンチモン、鉄の硝酸塩、硫酸塩、塩化物などが挙げられる。
【００１７】
本発明では、前記触媒の存在下、次のような反応条件で前記α−ヒドロキシカルボン酸エステルと前記分子状酸素を気相接触反応させてα−ケトン酸エステルを製造することができる。
即ち、この気相接触反応は、通常、反応温度が１５０〜４００℃、好ましくは２００〜３５０℃で、反応圧力が常圧から５ｋｇ／ｃｍ³ の加圧の条件下、触媒を充填した反応器に、α−ヒドロキシカルボン酸エステルを触媒１ｇ当たり０．２〜６．０ｇ／ｈｒ、好ましくは０．３〜３．０ｇ／ｈｒ、そして分子状酸素を触媒１ｇ当たり０．５〜３０ｍｌ／ｍｉｎ、好ましくは１〜１５ｍｌ／ｍｉｎの流量でフィードして行われる。このとき、α−ヒドロキシカルボン酸エステルに対する酸素のモル比（酸素／α−ヒドロキシカルボン酸エステル）は通常０．３〜５、好ましくは０．５〜２である。
なお、反応器は気相流通式の反応が行えるものであれば特に制限はなく、触媒の存在形態も、公知の固定床、流動床、沸騰床などいずれのものでもよいが、通常固定床が好適である。
【００１８】
また、本発明では、前記α−ヒドロキシカルボン酸エステルは、アルコール、水、アセトニトリル、トルエン、シクロヘキサンなどの前記反応に不活性な溶媒で希釈してフィードすることも可能で、これらの溶媒で希釈することによってα−ケトン酸エステルの選択率を向上させることができる。このとき、α−ヒドロキシカルボン酸エステルに対する溶媒の重量比（溶媒／α−ヒドロキシカルボン酸エステル）は通常０．０２〜１０、好ましくは０．０４〜８である。なお、アルコールとしては、メタノール、エタノール、ｎ−プロパノール、ｉ−プロパノール、ｎ−ブタノール、ｎ−ペンタノール、ｎ−ヘキサノール等の炭素数１〜６の脂肪族低級アルコールが使用されるが、中でもメタノール、エタノールが好ましい。
【００１９】
以上のようにして、前記のα−ケト酸エステルが未反応のα−ヒドロキシカルボン酸エステルや副生する水などと共に得られるが、目的のα−ケトン酸エステルは蒸留等の公知の方法によって分離精製することができる。
【００２０】
【実施例】
次に、実施例及び比較例を挙げて本発明を具体的に説明する。
なお、各実施例及び比較例におけるα−ケトン酸エステルの空時収量（ｇ／ｌ・ｈｒ）、α−ヒドロキシカルボン酸エステルの転化率（％）、α−ケトン酸エステルの選択率（％）及びα−ケトン酸エステルの収率（％）は次式により求めた。
【００２１】
【数１】

【００２２】
【数２】

【００２３】
【数３】

【００２４】
【数４】

【００２５】
実施例１
〔触媒の調製〕
水３ｍｌに硝酸第二銅三水塩〔Ｃｕ（ＮＯ₃ ）₂ ・３Ｈ₂ Ｏ〕２．４４ｇ（１０．０ｍｍｏｌ）と８５％リン酸０．７７ｇ（６．６８ｍｍｏｌ）を溶解した触媒調製液に、粒径３ｍｍ、比表面積１ｍ² ／ｇ以下、シリカ含量１１重量％の炭化ケイ素（ＴＬ−Ｓ５１：フジミ製）１１．２ｇを加えて０．５時間含浸を行った後、真空下、４０℃で水分を除去した。次いで、この含浸物を空気中１１０℃で１２時間乾燥し、更に、空気中４００℃及び８００℃でそれぞれ３時間焼成して触媒を調製した。得られた触媒のリン酸銅担持量は蛍光Ｘ線分析より銅原子換算で５．３重量％であった。
【００２６】
〔グリオキシル酸メチルの製造〕
上記触媒８ｍｌを内径９ｍｍのガラス製反応管に充填し、更にその上にガラスビーズ１４ｇを充填した後、反応管を電気炉中に垂直に設置して触媒層内の温度が表１に示す温度になるように電気炉を加熱制御した。この反応管の上部から、メタノール／グリコール酸メチル（重量比）＝１のグリコール酸エステル溶液１１．６ｇ／ｈｒ、及び空気２００ｍｌ／ｍｉｎと窒素ガス９４ｍｌ／ｍｉｎとの混合ガスをフィードしながら、常圧下、前記の反応温度で１時間気相接触反応を行って、反応管を通過した生成物を氷冷したトラップに補集した。
トラップに補集された反応生成物をガスクロマトグラフィーにより分析したところ、グリオキシル酸メチルの空時収量が５６５ｇ／ｌ・ｈｒで、グリコール酸メチルの転化率が８９．６％、グリオキシル酸メチルの選択率が８８．９％、グリオキシル酸メチルの収率が８０．０％であった。
【００２７】
実施例２
〔触媒の調製〕
実施例１において、触媒調製液を、水３ｍｌに硝酸第二銅三水塩〔Ｃｕ（ＮＯ₃ ）₂ ・３Ｈ₂ Ｏ〕２．４４ｇ（１０．０ｍｍｏｌ）、硝酸第二鉄九水塩〔Ｆｅ（ＮＯ₃ ）₃ ・９Ｈ₂ Ｏ〕０．８１ｇ（２．０ｍｍｏｌ）及び８５％リン酸１．０５ｇ（９．１ｍｍｏｌ）を溶解した液に変えたことのほかは、実施例１と同様に触媒を調製した。得られた触媒の分析結果を表１に示す。
〔グリオキシル酸メチルの製造〕
実施例１において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例１と同様に気相接触反応を行った。その結果を表１に示す。
【００２８】
実施例３
〔触媒の調製〕
実施例１において、触媒調製液を、水３ｍｌに硝酸第二銅三水塩〔Ｃｕ（ＮＯ₃ ）₂ ・３Ｈ₂ Ｏ〕２．４４ｇ（１０．０ｍｍｏｌ）、硝酸第二鉄九水塩〔Ｆｅ（ＮＯ₃ ）₃ ・９Ｈ₂ Ｏ〕２．０３ｇ（５．０ｍｍｏｌ）及び８５％リン酸１．３６ｇ（１１．８ｍｍｏｌ）を溶解した液に変えたことのほかは、実施例１と同様に触媒を調製した。得られた触媒の分析結果を表１に示す。
〔グリオキシル酸メチルの製造〕
実施例１において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例１と同様に気相接触反応を行った。その結果を表１に示す。
【００２９】
実施例４
〔触媒の調製〕
実施例１において、触媒調製液を、水３ｍｌに硝酸第二銅三水塩〔Ｃｕ（ＮＯ₃ ）₂ ・３Ｈ₂ Ｏ〕２．４４ｇ（１０．０ｍｍｏｌ）、硝酸第二鉄九水塩〔Ｆｅ（ＮＯ₃ ）₃ ・９Ｈ₂ Ｏ〕２．７１ｇ（６．７ｍｍｏｌ）及び８５％リン酸１．５６ｇ（１３．５ｍｍｏｌ）を溶解した液に変えたことのほかは、実施例１と同様に触媒を調製した。得られた触媒の分析結果を表１に示す。
〔グリオキシル酸メチルの製造〕
実施例１において、触媒を上記触媒８ｍｌに変え、空気のフィード量を８０ｍｌ／ｍｉｎに変えたことのほかは、実施例１と同様に気相接触反応を行った。その結果を表１に示す。
【００３０】
実施例５
〔触媒の調製〕
実施例１において、触媒調製液を、水３ｍｌに硝酸第二銅三水塩〔Ｃｕ（ＮＯ₃ ）₂ ・３Ｈ₂ Ｏ〕２．４４ｇ（１０．０ｍｍｏｌ）、硝酸第二鉄九水塩〔Ｆｅ（ＮＯ₃ ）₃ ・９Ｈ₂ Ｏ〕４．０４ｇ（１０．０ｍｍｏｌ）及び８５％リン酸１．９５ｇ（１６．９ｍｍｏｌ）を溶解した液に変えたことのほかは、実施例１と同様に触媒を調製した。得られた触媒の分析結果を表１に示す。
〔グリオキシル酸メチルの製造〕
実施例１において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例１と同様に気相接触反応を行った。その結果を表１に示す。
【００３１】
実施例６
〔触媒の調製〕
実施例１において、触媒調製液を、水３ｍｌに硝酸第二銅三水塩〔Ｃｕ（ＮＯ₃ ）₂ ・３Ｈ₂ Ｏ〕２．４４ｇ（１０．０ｍｍｏｌ）、硝酸第二鉄九水塩〔Ｆｅ（ＮＯ₃ ）₃ ・９Ｈ₂ Ｏ〕５．３７ｇ（１３．３ｍｍｏｌ）及び８５％リン酸２．３４ｇ（２０ｍｍｏｌ）を溶解した液に変えたことのほかは、実施例１と同様に触媒を調製した。得られた触媒の分析結果を表１に示す。
〔グリオキシル酸メチルの製造〕
実施例１において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例１と同様に気相接触反応を行った。その結果を表１に示す。
【００３２】
比較例１
〔触媒の調製〕
実施例１において、触媒調製液を、水３ｍｌに硝酸第二鉄九水塩〔Ｆｅ（ＮＯ₃ ）₃ ・９Ｈ₂ Ｏ〕４．０４ｇ（１０．０ｍｍｏｌ）及び８５％リン酸１．２１ｇ（１０．５ｍｏｌ）を溶解した液に変えたことのほかは、実施例１と同様に触媒を調製した。得られた触媒の分析結果を表１に示す。
〔グリオキシル酸メチルの製造〕
実施例１において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例１と同様に気相接触反応を行った。その結果を表１に示す。
【００３３】
実施例７
〔触媒の調製〕
実施例１において、触媒調製液を、水３ｍｌに硝酸第二銅三水塩〔Ｃｕ（ＮＯ₃ ）₂ ・３Ｈ₂ Ｏ〕２．４４ｇ（１０．０ｍｍｏｌ）、硝酸ランタン六水塩〔Ｌａ（ＮＯ₃ ）₃ ・６Ｈ₂ Ｏ〕０．８７ｇ（２．０ｍｍｏｌ）及び８５％リン酸１．０５ｇ（９．１ｍｍｏｌ）を溶解した液に変えたことのほかは、実施例１と同様に触媒を調製した。得られた触媒の分析結果を表１に示す。
〔グリオキシル酸メチルの製造〕
実施例１において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例１と同様に気相接触反応を行った。その結果を表１に示す。
【００３４】
実施例８
〔触媒の調製〕
実施例４と同様に触媒を調製した。得られた触媒の分析結果を表１に示す。
〔グリオキシル酸メチルの製造〕
実施例１において、触媒を上記触媒８ｍｌに変え、空気のフィード量を８０ｍｌ／ｍｉｎに変え、更に該グリコール酸エステル溶液に代えて水／グリコール酸メチル（重量比）＝５／９５のグリコール酸エステル溶液６．１ｇ／ｈｒをフィードしたことのほかは、実施例１と同様に気相接触反応を行った。その結果を表１に示す。
【００３５】
実施例９
〔触媒の調製〕
実施例５と同様に触媒を調製した。得られた触媒の分析結果を表１に示す。
〔グリオキシル酸メチルの製造〕
実施例８において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例８と同様に気相接触反応を行った。その結果を表１に示す。
【００３６】
【表１】

【００３７】
実施例１０
〔触媒の調製〕
実施例１と同様に触媒を調製した。得られた触媒の分析結果を表２に示す。
〔グリオキシル酸メチルの製造〕
実施例１において、触媒を上記触媒８ｍｌに変え、該グリコール酸エステル溶液に代えてグリコール酸メチル５．８ｇ／ｈｒをフィードしたことのほかは、実施例１と同様に気相接触反応を行った。その結果を表２に示す。
【００３８】
比較例２
〔触媒の調製〕
実施例１において、触媒調製液を、水３ｍｌに硝酸第二銅三水塩〔Ｃｕ（ＮＯ₃ ）₂ ・３Ｈ₂ Ｏ〕２．４４ｇ（１０．０ｍｍｏｌ）を溶解した液に変えたことのほかは、実施例１と同様に触媒を調製した。得られた触媒は酸化第二銅のＸ線回折スペクトルを示した。他の分析結果を表２に示す。
〔グリオキシル酸メチルの製造〕
実施例１０において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例１０と同様に気相接触反応を行った。その結果を表２に示す。
【００３９】
実施例１１
〔触媒の調製〕
実施例２と同様に触媒を調製した。得られた触媒の分析結果を表２に示す。
〔グリオキシル酸メチルの製造〕
実施例１０において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例１０と同様に気相接触反応を行った。その結果を表２に示す。
【００４０】
実施例１２
〔触媒の調製〕
実施例３と同様に触媒を調製した。得られた触媒の分析結果を表２に示す。
〔グリオキシル酸メチルの製造〕
実施例１０において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例１０と同様に気相接触反応を行った。その結果を表２に示す。
【００４１】
実施例１３
〔触媒の調製〕
実施例４と同様に触媒を調製した。得られた触媒の分析結果を表２に示す。
〔グリオキシル酸メチルの製造〕
実施例１０において、触媒を上記触媒８ｍｌに変え、空気のフィード量を８０ｍｌ／ｍｉｎに変えたことのほかは、実施例１０と同様に気相接触反応を行った。その結果を表２に示す。
【００４２】
実施例１４
〔触媒の調製〕
実施例５と同様に触媒を調製した。得られた触媒の分析結果を表２に示す。
〔グリオキシル酸メチルの製造〕
実施例１０において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例１０と同様に気相接触反応を行って反応生成物を分析した。その結果を表２に示す。
【００４３】
実施例１５
〔触媒の調製〕
実施例６と同様に触媒を調製した。得られた触媒の分析結果を表２に示す。
〔グリオキシル酸メチルの製造〕
実施例１０において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例１０と同様に気相接触反応を行った。その結果を表２に示す。
【００４４】
比較例３
〔触媒の調製〕
比較例１と同様に触媒を調製した。得られた触媒の分析結果を表２に示す。
〔グリオキシル酸メチルの製造〕
実施例１０において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例１０と同様に気相接触反応を行った。その結果を表２に示す。
【００４５】
実施例１６
〔触媒の調製〕
実施例７と同様に触媒を調製した。得られた触媒の分析結果を表２に示す。
〔グリオキシル酸メチルの製造〕
実施例１０において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例１０と同様に気相接触反応を行った。その結果を表１に示す。
【００４６】
【表２】

【００４７】
実施例１７
〔触媒の調製〕
実施例５において、炭化ケイ素を、粒径４ｍｍ、比表面積１ｍ² ／ｇ以下、シリカ含量０．５重量％の炭化ケイ素（ＴＳＳ−９９１７５：東海高熱製）１１．２ｇに変えたことのほかは、実施例５と同様に触媒を調製した。得られた触媒の分析結果を表３に示す。
〔グリオキシル酸メチルの製造〕
実施例１において、触媒を上記触媒８ｍｌに変え、空気のフィード量を８０ｍｌ／ｍｉｎに変えたことのほかは、実施例１と同様に気相接触反応を行った。その結果を表３に示す。
【００４８】
実施例１８
〔触媒の調製〕
実施例１７と同様に触媒を調製した。得られた触媒の分析結果を表３に示す。
〔グリオキシル酸メチルの製造〕
実施例１７において、触媒を上記触媒８ｍｌに変え、該グリコール酸エステル溶液に代えてグリコール酸メチル５．８ｇ／ｈｒをフィードしたことのほかは、実施例１７と同様に気相接触反応を行った。その結果を表３に示す。
【００４９】
比較例４
〔触媒の調製〕
実施例１７において、触媒調製液を、水３ｍｌに硝酸第二鉄九水塩〔Ｆｅ（ＮＯ₃ ）₃ ・９Ｈ₂ Ｏ〕４．０４ｇ（１０．０ｍｍｏｌ）及び８５％リン酸１．２１ｇ（１０．５ｍｏｌ）を溶解した液に変えたことのほかは、実施例１７と同様に触媒を調製した。得られた触媒の分析結果を表３に示す。
〔グリオキシル酸メチルの製造〕
実施例１７において、触媒を上記触媒８ｍｌに変え、空気のフィード量を２００ｍｌ／ｍｉｎに変え、更に該グリコール酸エステル溶液に代えてグリコール酸メチル５．８ｇ／ｈｒをフィードしたことのほかは、実施例１７と同様に気相接触反応を行った。その結果を表３に示す。
【００５０】
実施例１９
〔触媒の調製〕
実施例５において、炭化ケイ素を、粒径４ｍｍ、比表面積１ｍ² ／ｇ以下、シリカ含量７．５重量％の炭化ケイ素（ＴＳＳ−９０３０６：東海高熱製）１１．２ｇに変えたことのほかは、実施例５と同様に触媒を調製した。得られた触媒の分析結果を表３に示す。
〔グリオキシル酸メチルの製造〕
実施例１７において、触媒を上記触媒８ｍｌに変え、空気のフィード量を１６０ｍｌ／ｍｉｎに変えたことのほかは、実施例１７と同様に気相接触反応を行った。その結果を表３に示す。
【００５１】
実施例２０
〔触媒の調製〕
実施例１９と同様に触媒を調製した。得られた触媒の分析結果を表３に示す。
〔グリオキシル酸メチルの製造〕
実施例１９において、触媒を上記触媒８ｍｌに変え、該グリコール酸エステル溶液をアセトニトリル／グリコール酸メチル（重量比）＝１の溶液に変えたことのほかは、実施例１９と同様に気相接触反応を行った。その結果を表３に示す。
【００５２】
実施例２１
〔触媒の調製〕
実施例１９と同様に触媒を調製した。得られた触媒の分析結果を表３に示す。
〔グリオキシル酸メチルの製造〕
実施例１９において、触媒を上記触媒８ｍｌに変え、空気のフィード量を８０ｍｌ／ｍｉｎに変え、更に該グリコール酸エステル溶液に代えてグリコール酸メチル５．８ｇ／ｈｒをフィードしたことのほかは、実施例１９と同様に気相接触反応を行った。その結果を表３に示す。
【００５３】
比較例５
〔触媒の調製〕
実施例１９において、触媒調製液を、水３ｍｌに硝酸第二鉄九水塩〔Ｆｅ（ＮＯ₃ ）₃ ・９Ｈ₂ Ｏ〕４．０４ｇ（１０．０ｍｍｏｌ）及び８５％リン酸１．２１ｇ（１０．５ｍｍｏｌ）を溶解した液に変えたことのほかは、実施例１６と同様に触媒を調製した。得られた触媒の分析結果を表３に示す。
〔グリオキシル酸メチルの製造〕
実施例１９において、触媒を上記触媒８ｍｌに変え、空気のフィード量を２００ｍｌ／ｍｉｎに変え、更に該グリコール酸エステル溶液に代えてグリコール酸メチル５．８ｇ／ｈｒをフィードしたことのほかは、実施例１９と同様に気相接触反応を行った。その結果を表３に示す。
【００５４】
【表３】

【００５５】
実施例２２
〔触媒の調製〕
実施例５において、炭化ケイ素を、粒径３ｍｍ、比表面積１ｍ² ／ｇ以下、シリカ含量１３重量％のα−アルミナ（ＡＬ−Ｓ７３：フジミ製）１１．２ｇに変えたことのほかは実施例５と同様に触媒を調製した。得られた触媒の分析結果を表４に示す。
〔グリオキシル酸メチルの製造〕
実施例１において、触媒を上記触媒８ｍｌに変え、該グリコール酸エステル溶液に代えてメタノール／グリコール酸メチル（重量比）＝３／７のグリコール酸エステル溶液８．３ｇ／ｈｒをフィードしたことのほかは、実施例１と同様に気相接触反応を行った。その結果を表４に示す。
【００５６】
実施例２３
〔触媒の調製〕
実施例２２と同様に触媒を調製した。得られた触媒の分析結果を表４に示す。
〔グリオキシル酸メチルの製造〕
実施例２２において、触媒を上記触媒８ｍｌに変え、該グリコール酸エステル溶液に代えてグリコール酸メチル５．８ｇ／ｈｒをフィードしたことのほかは、実施例２２と同様に気相接触反応を行った。その結果を表４に示す。
【００５７】
比較例６
〔触媒の調製〕
実施例２２において、触媒調製液を、水３ｍｌに硝酸第二鉄九水塩〔Ｆｅ（ＮＯ₃ ）₃ ・９Ｈ₂ Ｏ〕４．０４ｇ（１０．０ｍｍｏｌ）及び８５％リン酸１．２１ｇ（１０．５ｍｍｏｌ）を溶解した液に変えたことのほかは、実施例２２と同様に触媒を調製した。得られた触媒の分析結果を表４に示す。
〔グリオキシル酸メチルの製造〕
実施例２２において、触媒を上記触媒８ｍｌに変え、該グリコール酸エステル溶液に代えてグリコール酸メチル５．８ｇ／ｈｒをフィードしたことのほかは、実施例２２と同様に気相接触反応を行った。その結果を表４に示す。
【００５８】
実施例２４
〔触媒の調製〕
実施例５において、炭化ケイ素を、粒径４．７ｍｍ、比表面積０．０５ｍ² ／ｇ以下、シリカ含量１２重量％のα−アルミナ（ＳＡ−５２０５：ノートン製）に変えたことのほかは、実施例５と同様に触媒を調製した。得られた触媒の分析結果を表４に示す。
〔グリオキシル酸メチルの製造〕
実施例２２において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例２２と同様に気相接触反応を行った。その結果を表４に示す。
【００５９】
実施例２５
〔触媒の調製〕
実施例２４と同様に触媒を調製した。得られた触媒の分析結果を表４に示す。
〔グリオキシル酸メチルの製造〕
実施例２２において、触媒を上記触媒８ｍｌに変え、該グリコール酸エステル溶液に代えてグリコール酸メチル５．８ｇ／ｈｒをフィードしたことのほかは、実施例２２と同様に気相接触反応を行った。その結果を表４に示す。
【００６０】
比較例７
〔触媒の調製〕
実施例２４において、触媒調製液を、水３ｍｌに硝酸第二鉄九水和物〔Ｆｅ（ＮＯ₃ ）₃ ・９Ｈ₂ Ｏ〕４．０４ｇ（１０．０ｍｍｏｌ）及び８５％リン酸１．２１ｇ（１０．５ｍｍｏｌ）を溶解した液に変えたことのほかは、実施例２４と同様に触媒を調製した。得られた触媒の分析結果を表４に示す。
〔グリオキシル酸メチルの製造〕
実施例２２において、触媒を上記触媒８ｍｌに変え、該グリコール酸エステル溶液に代えてグリコール酸メチル５．８ｇ／ｈｒをフィードしたことのほかは、実施例２２と同様に気相接触反応を行った。その結果を表４に示す。
【００６１】
【表４】

【００６２】
実施例２６
〔触媒の調製〕
実施例１９と同様に触媒を調製した。得られた触媒の分析結果を表５に示す。〔ピルビン酸メチルの製造〕
実施例１において、触媒を上記触媒８ｍｌに変え、空気のフィード量を９０ｍｌ／ｍｉｎに、窒素のフィード量を１８０ｍｌ／ｍｉｎに変え、更に該グリコール酸エステル溶液に代えてメタノール／乳酸メチル（重量比）＝５のα−ヒドロキシカルボン酸エステル溶液１５．６ｇ／ｈｒをフィードしたことのほかは、実施例１と同様に気相接触反応を行って、α−ケトン酸エステルとしてピルビン酸メチルを得た。その結果を表５に示す。
【００６３】
実施例２７
〔触媒の調製〕
実施例１９において、触媒調製液を、水４ｍｌに硝酸第二銅三水塩〔Ｃｕ（ＮＯ₃ ）₂ ・３Ｈ₂ Ｏ〕３．６６ｇ（１５．０ｍｍｏｌ）、硝酸第二鉄九水塩〔Ｆｅ（ＮＯ₃ ）₃ ・９Ｈ₂ Ｏ〕４．０４ｇ（１０．０ｍｍｏｌ）及び８５％リン酸２．３３ｇ（２０．２ｍｍｏｌ）を溶解した溶液に変えたことのほかは、実施例１９と同様に触媒を調製した。得られた触媒の分析結果を表５に示す。
〔ピルビン酸メチルの製造〕
実施例２６において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例２６と同様に気相接触反応を行って、α−ケトン酸エステルとしてピルビン酸メチルを得た。その結果を表５に示す。
【００６４】
実施例２８
〔触媒の調製〕
実施例１９において、炭化ケイ素を、粒径４．７ｍｍ、比表面積０．０５ｍ² ／ｇ以下、シリカ含量１１．８重量％のα−アルミナ（ＳＡ−５０２０５：ノートン製）に変えたことのほかは、実施例１９と同様に触媒を調製した。得られた触媒の分析結果を表５に示す。
〔ピルビン酸メチルの製造〕
実施例２６において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例２６と同様に気相接触反応を行って、α−ケトン酸エステルとしてピルビン酸メチルを得た。その結果を表５に示す。
【００６５】
比較例８
〔触媒の調製〕
比較例５と同様に触媒を調製した。得られた触媒の分析結果を表５に示す。
〔ピルビン酸メチルの製造〕
実施例２６において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例２６と同様に気相接触反応を行って、α−ケトン酸エステルとしてピルビン酸メチルを得た。その結果を表５に示す。
【００６６】
実施例２９
〔触媒の調製〕
実施例１９と同様に触媒を調製した。得られた触媒の分析結果を表５に示す。
〔フェニルグリオキシル酸メチルの製造〕
実施例１において、触媒を上記触媒８ｍｌに変え、空気のフィード量を３５ｍｌ／ｍｉｎに、窒素のフィード量を７０ｍｌ／ｍｉｎに変え、更に該グリコール酸エステル溶液に代えてメタノール／マンデル酸メチル（重量比）＝６のα−ヒドロキシカルボン酸エステル溶液１７．０ｇ／ｈｒをフィードしたことのほかは、実施例１と同様に気相接触反応を行って、α−ケトン酸エステルとしてフェニルグリオキシル酸メチルを得た。その結果を表５に示す。
【００６７】
実施例３０
〔触媒の調製〕
実施例１９と同様に触媒を調製した。得られた触媒の分析結果を表５に示す。
〔フェニルグリオキシル酸メチルの製造〕
実施例２９において、触媒を上記触媒８ｍｌに変え、空気のフィード量を５６ｍｌ／ｍｉｎに変え、更に該α−ヒドロキシカルボン酸エステル溶液のフィード量を３０．７ｇ／ｈｒに変えたことのほかは、実施例２９と同様に気相接触反応を行って、α−ケトン酸エステルとしてフェニルグリオキシル酸メチルを得た。その結果を表５に示す。
【００６８】
実施例３１
〔触媒の調製〕
実施例２８と同様に触媒を調製した。得られた触媒の分析結果を表５に示す。
〔フェニルグリオキシル酸メチルの製造〕
実施例２９において、触媒を上記触媒８ｍｌに変えたことのほかは、実施例２９と同様に気相接触反応を行って、α−ケトン酸エステルとしてフェニルグリオキシル酸メチルを得た。その結果を表５に示す。
【００６９】
【表５】

【００７０】
【発明の効果】
本発明により、公知のα−ケトン酸エステルの製造法が有していた、原料の種類、触媒の価格、原料の転化率及び目的物の選択率（即ち、目的物の収率）、目的物の生成速度（空時収量）に関する問題を解決することができる。即ち、容易に調製できる安価で高活性のリン酸銅触媒を通常の反応器に充填して、α−ヒドロキシカルボン酸エステルと分子状酸素を気相で反応させて、α−ヒドロキシカルボン酸エステルの転化率を高めた状態で、グリオキシル酸エステルを含めたα−ケトン酸エステルを、高選択率（即ち、高収率）で、しかも高い生成速度（空時収量）でもって製造することができる。[0001]
[Industrial applications]
The present invention relates to a method for producing an α-ketone acid ester by subjecting an α-hydroxycarboxylic acid ester and molecular oxygen to gas phase contact reaction using a novel catalyst. The α-ketone acid ester is a compound useful as a raw material for synthesizing various chemicals, and especially a compound very useful as a raw material for synthesizing α-amino acids.
[0002]
[Prior art]
Conventionally, as a method for producing an α-ketone acid ester, a method is known in which an α-hydroxycarboxylic acid ester and molecular oxygen are subjected to a gas phase contact reaction in the presence of various catalysts.
For example, as a method for producing glyoxylate, US Pat. No. 4,340,748 discloses that at least one element of vanadium, molybdenum, silver, copper, tin, antimony, bismuth, an element of the first main group of the periodic table, Although a method using a catalyst containing at least one of the two main group elements is disclosed, productivity is low because the production rate (space-time yield) is low and the amount of gas fed is very large. There is a problem that it is not high. Further, this patent also states that the main group elements of Groups 3 to 5 of the periodic table are effective, but there is no specific example.
[0003]
JP-A-60-152442 discloses a method using expensive silver as a catalyst, but in this method, it is necessary to suppress the conversion of glycolate in order to increase the selectivity of glyoxylate, The yield of glyoxylate is as low as about 62%, which is determined from the maximum conversion of glycolate of about 69% and the selectivity of glyoxylate about 89%.
Japanese Patent Application Laid-Open No. 61-97247 discloses a method using a catalyst containing an expensive silver and phosphorus compound. In this method, the conversion of glycolic acid ester is as high as 95%, but the conversion of glyoxylic acid is high. There is a problem that the selectivity of the ester is as low as about 8% and the yield of glyoxylate is low. As described above, in the production of glyoxylate, the effect of adding phosphorus to an element effective as a catalyst was not recognized at all.
[0004]
Japanese Patent Application Laid-Open No. 2-91046 discloses a method using a catalyst in which ferric phosphate is supported on an α-alumina carrier. In this method, the conversion of glycolic acid ester and the selectivity of glyoxylic acid ester are disclosed. The yield of glyoxylate required from the above is not so high, the gas flow rate is large, the preparation of the catalyst requires complicated pretreatment, and the reactor requires a preheating device before the reactor. There is a problem.
[0005]
On the other hand, as another method for producing an α-ketone acid ester, JP-A-61-97247 discloses the use of a catalyst containing an expensive silver and phosphorus compound, ethyl pyruvate, methyl phenylglyoxylate and phenyl. A method for producing methyl pyruvate and the like is disclosed. However, this method has problems in that the feed amount of the raw material is small and there is a problem in productivity, and that expensive silver is used for the catalyst. According to this method, the conversion of the α-hydroxycarboxylic acid ester is 99%, 90%, and 92%, respectively, and the corresponding α-ketone acid ester is obtained with a selectivity of 80%, 86%, and 70%, respectively. However, the yield of α-ketone esters is not satisfactory, and it is difficult to obtain glyoxylate esters in high yield among α-ketone esters as described above. .
Further, Bull. Chem. Soc. Jpn. , 66, 1542 (1993) discloses a method for producing ethyl pyruvate from ethyl lactate using oxides of molybdenum, iron, tin, bismuth, tellurium, titanium, and zirconium. The yield is not satisfactory at 80% or less.
[0006]
[Problems to be solved by the invention]
The present invention provides a gas phase contact reaction between α-hydroxycarboxylic acid ester and molecular oxygen using an inexpensive catalyst to convert α-ketonic acid ester including glyoxylic acid ester into α-hydroxycarboxylic acid ester. It is an object of the present invention to provide a method capable of producing at a high selectivity (that is, at a high yield) and at a high production rate (space-time yield).
[0007]
[Means for Solving the Problems]
An object of the present invention is to provide a method for producing an α-ketone acid ester, which comprises reacting an α-hydroxycarboxylic acid ester and molecular oxygen in the gas phase in the presence of a catalyst in which copper phosphate is supported on a carrier. Achieved.
[0008]
Hereinafter, the present invention will be described in detail.
The α-hydroxycarboxylic acid ester used in the present invention is a compound represented by the following general formula (I).
Embedded image

(Where R ¹ Represents a hydrogen atom or a substituent selected from an aliphatic lower alkyl group having 1 to 6 carbon atoms, a phenyl group and a benzyl group, ^Two Represents an aliphatic lower alkyl group having 1 to 6 carbon atoms)
[0009]
Specifically, glycolic acid esters such as methyl glycolate, ethyl glycolate, n-propyl glycolate, i-propyl glycolate, n-butyl glycolate, n-pentyl glycolate and n-hexyl glycolate, methyl lactate Lactic acid esters such as ethyl lactate, n-propyl lactate, i-propyl lactate, n-butyl lactate, n-pentyl lactate, n-hexyl lactate, methyl mandelate, ethyl mandelate, n-propyl mandelate, and mandelic acid i -Propyl, n-butyl mandelate, n-pentyl mandelate, n-hexyl mandelate, methyl α-hydroxycinnamate, ethyl α-hydroxycinnamate, n-propyl α-hydroxycinnamate, α I-propyl hydroxycinnamate, n-butyl α-hydroxycinnamate, α-hydroxy Proxy cinnamic acid n- butyl, alpha-hydroxy cinnamic acid n- pentyl, alpha-like hydroxycinnamic acid n- hexyl, etc. alpha-hydroxy cinnamic acid ester.
[0010]
The α-ketone acid ester obtained in the present invention is a compound represented by the following general formula (II).
Embedded image

(Where R ¹ Represents a hydrogen atom or a substituent selected from an aliphatic lower alkyl group having 1 to 6 carbon atoms, a phenyl group and a benzyl group, ^Two Represents an aliphatic lower alkyl group having 1 to 6 carbon atoms)
[0011]
Specifically, glyoxylates such as methyl glyoxylate, ethyl glyoxylate, n-propyl glyoxylate, i-propyl glyoxylate, n-butyl glyoxylate, n-pentyl glyoxylate, n-hexyl glyoxylate, and pyruvate Pyruvates such as methyl, ethyl pyruvate, n-propyl pyruvate, i-propyl pyruvate, n-butyl pyruvate, n-pentyl pyruvate, n-hexyl pyruvate, methyl phenylglyoxylate, ethyl phenylglyoxylate Phenylglyoxylates such as n-propyl phenylglyoxylate, i-propyl phenylglyoxylate, n-butyl phenylglyoxylate, n-pentyl phenylglyoxylate and n-hexyl phenylglyoxylate Phenylpyruvate esters such as methyl phenylpyruvate, ethyl phenylpyruvate, n-propyl phenylpyruvate, i-propyl phenylpyruvate, n-butyl phenylpyruvate, n-pentyl phenylpyruvate and n-hexyl phenylpyruvate And the like.
[0012]
Air is generally used as the molecular oxygen used in the present invention, but air or oxygen gas diluted with an inert gas such as nitrogen or argon may be used. At this time, the air or oxygen gas is diluted so that the molar ratio of the inert gas to oxygen is usually 2 to 50, preferably 4 to 30.
[0013]
As the catalyst used in the present invention, a catalyst in which copper phosphate is supported on a carrier is used. Copper phosphate is usually 1 to 20% by weight, particularly 2 to 15% by weight in terms of copper atom, based on the carrier. It is preferably carried.
[0014]
Examples of the carrier used in the present invention include silicon carbide, α-alumina, zirconium oxide, titanium oxide, and silica alumina, and among them, silicon carbide and α-alumina are preferable. More preferably, silicon carbide and α-alumina having a silica content of 30% by weight or less, particularly 25% by weight or less are used. The specific surface area of the carrier measured by the BET method is usually 0.01 to 20 m ^Two / G, especially 0.02 to 10 m ^Two / G is preferred. Further, the particle size of the carrier is usually preferably 1 to 20 mm, particularly preferably about 1 to 10 mm.
[0015]
In the catalyst, a metal other than copper may be supported in any form such as a phosphate, an oxide, or a metal. Examples of other metals include alkali metals such as lithium and potassium, alkaline earth metals such as magnesium and calcium, lanthanide metals such as lanthanum and cerium, and molybdenum, tin, manganese, bismuth, cobalt, silver, lead, and antimony. However, it is preferable that each of these metals is supported alone or plurally on a carrier at an atomic ratio to copper (other metal / copper) of usually less than 2.0.
[0016]
The method for preparing the catalyst is not particularly limited as long as copper phosphate is supported on the carrier, and a known method such as an impregnation method or an evaporation to dryness method can be used. For example, copper and, if necessary, salts of other metals are dissolved in water, and a solution obtained by adding a stoichiometric amount of phosphoric acid to the carrier is impregnated with the carrier, and the carrier is dried at about 110 ° C. in air. It can be prepared by a method of firing at a temperature of 400 to 900 ° C.
The salts of copper and other metals include copper salts such as cupric nitrate, copper sulfate and cupric chloride; alkali metals such as lithium and potassium; alkaline earth metals such as magnesium and calcium; and lanthanum. And lanthanide metals such as cerium, molybdenum, tin, manganese, bismuth, cobalt, silver, lead, antimony, and nitrates, sulfates and chlorides of iron.
[0017]
In the present invention, in the presence of the catalyst, the α-hydroxycarboxylic acid ester and the molecular oxygen are subjected to a gas phase contact reaction under the following reaction conditions to produce an α-ketone acid ester.
That is, this gas phase contact reaction is usually performed at a reaction temperature of 150 to 400 ° C., preferably 200 to 350 ° C., and a reaction pressure of normal pressure to 5 kg / cm. ^Three In a reactor filled with a catalyst, α-hydroxycarboxylic acid ester is added in an amount of 0.2 to 6.0 g / hr, preferably 0.3 to 3.0 g / hr, and preferably 0.3 to 3.0 g / hr per 1 g of the catalyst. Oxygen is fed at a flow rate of 0.5 to 30 ml / min, preferably 1 to 15 ml / min per gram of the catalyst. At this time, the molar ratio of oxygen to α-hydroxycarboxylic acid ester (oxygen / α-hydroxycarboxylic acid ester) is usually 0.3 to 5, preferably 0.5 to 2.
The reactor is not particularly limited as long as it can perform a gas-phase flow reaction, and the catalyst may be in any form such as a known fixed bed, a fluidized bed, or a boiling bed. It is suitable.
[0018]
In the present invention, the α-hydroxycarboxylic acid ester can be fed by diluting with an inert solvent such as alcohol, water, acetonitrile, toluene, and cyclohexane for the reaction, and diluting with these solvents. This can improve the selectivity of the α-ketone acid ester. At this time, the weight ratio of the solvent to the α-hydroxycarboxylic acid ester (solvent / α-hydroxycarboxylic acid ester) is usually from 0.02 to 10, preferably from 0.04 to 8. As the alcohol, an aliphatic lower alcohol having 1 to 6 carbon atoms such as methanol, ethanol, n-propanol, i-propanol, n-butanol, n-pentanol, and n-hexanol is used. And ethanol is preferred.
[0019]
As described above, the above-mentioned α-keto acid ester is obtained together with unreacted α-hydroxycarboxylic acid ester and water produced as a by-product, but the target α-keto acid ester is separated by a known method such as distillation. It can be purified.
[0020]
【Example】
Next, the present invention will be specifically described with reference to Examples and Comparative Examples.
The space-time yield (g / l · hr) of α-ketone acid ester, conversion rate of α-hydroxycarboxylic acid ester (%), selectivity of α-ketone acid ester (%) in each of Examples and Comparative Examples And the yield (%) of α-ketone acid ester was determined by the following equation.
[0021]
(Equation 1)

[0022]
(Equation 2)

[0023]
[Equation 3]

[0024]
(Equation 4)

[0025]
Example 1
(Preparation of catalyst)
Cupric nitrate trihydrate [Cu (NO _Three ) _Two ・ 3H _Two O] 2.44 g (10.0 mmol) of 85% phosphoric acid and 0.77 g (6.68 mmol) of 85% phosphoric acid were dissolved in the prepared catalyst solution to give a particle diameter of 3 mm and a specific surface area of 1 m. ^Two / G or less, 11.2 g of silicon carbide (TL-S51: manufactured by Fujimi) having a silica content of 11% by weight was added and impregnated for 0.5 hour, and then water was removed at 40 ° C under vacuum. Next, the impregnated material was dried in air at 110 ° C. for 12 hours, and further calcined in air at 400 ° C. and 800 ° C. for 3 hours to prepare a catalyst. The amount of copper phosphate carried on the resulting catalyst was 5.3% by weight in terms of copper atoms by fluorescent X-ray analysis.
[0026]
(Production of methyl glyoxylate)
After filling 8 ml of the above catalyst into a glass reaction tube having an inner diameter of 9 mm and further filling 14 g of glass beads thereon, the reaction tube was installed vertically in an electric furnace, and the temperature in the catalyst layer was set to the temperature shown in Table 1. The heating of the electric furnace was controlled so that While feeding 11.6 g / hr of a glycolic acid ester solution of methanol / methyl glycolate (weight ratio) = 1 and a mixed gas of 200 ml / min of air and 94 ml / min of nitrogen gas from the upper part of this reaction tube, Under pressure, the gas phase contact reaction was carried out at the above-mentioned reaction temperature for 1 hour, and the product passed through the reaction tube was collected in an ice-cooled trap.
When the reaction product collected in the trap was analyzed by gas chromatography, the space-time yield of methyl glyoxylate was 565 g / l · hr, the conversion of methyl glycolate was 89.6%, and the selection of methyl glyoxylate was performed. The yield was 88.9% and the yield of methyl glyoxylate was 80.0%.
[0027]
Example 2
(Preparation of catalyst)
In Example 1, a catalyst preparation solution was prepared by adding cupric nitrate trihydrate [Cu (NO _Three ) _Two ・ 3H _Two O] 2.44 g (10.0 mmol), ferric nitrate nonahydrate [Fe (NO _Three ) _Three ・ 9H _Two O] A catalyst was prepared in the same manner as in Example 1, except that 0.81 g (2.0 mmol) and 85% phosphoric acid 1.05 g (9.1 mmol) were dissolved. Table 1 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
A gas phase contact reaction was carried out in the same manner as in Example 1 except that the catalyst was changed to 8 ml of the above catalyst. Table 1 shows the results.
[0028]
Example 3
(Preparation of catalyst)
In Example 1, a catalyst preparation solution was prepared by adding cupric nitrate trihydrate [Cu (NO _Three ) _Two ・ 3H _Two O] 2.44 g (10.0 mmol), ferric nitrate nonahydrate [Fe (NO _Three ) _Three ・ 9H _Two O] A catalyst was prepared in the same manner as in Example 1, except that 2.03 g (5.0 mmol) and 1.36 g (11.8 mmol) of 85% phosphoric acid were dissolved. Table 1 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
A gas phase contact reaction was carried out in the same manner as in Example 1 except that the catalyst was changed to 8 ml of the above catalyst. Table 1 shows the results.
[0029]
Example 4
(Preparation of catalyst)
In Example 1, a catalyst preparation solution was prepared by adding cupric nitrate trihydrate [Cu (NO _Three ) _Two ・ 3H _Two O] 2.44 g (10.0 mmol), ferric nitrate nonahydrate [Fe (NO _Three ) _Three ・ 9H _Two O] A catalyst was prepared in the same manner as in Example 1, except that 2.71 g (6.7 mmol) and 1.56 g (13.5 mmol) of 85% phosphoric acid were dissolved. Table 1 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
A gas phase contact reaction was carried out in the same manner as in Example 1 except that the catalyst was changed to 8 ml of the catalyst and the air feed rate was changed to 80 ml / min. Table 1 shows the results.
[0030]
Example 5
(Preparation of catalyst)
In Example 1, a catalyst preparation solution was prepared by adding cupric nitrate trihydrate [Cu (NO _Three ) _Two ・ 3H _Two O] 2.44 g (10.0 mmol), ferric nitrate nonahydrate [Fe (NO _Three ) _Three ・ 9H _Two [O] A catalyst was prepared in the same manner as in Example 1 except that 4.04 g (10.0 mmol) and 1.95 g (16.9 mmol) of 85% phosphoric acid were dissolved. Table 1 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
A gas phase contact reaction was carried out in the same manner as in Example 1 except that the catalyst was changed to 8 ml of the above catalyst. Table 1 shows the results.
[0031]
Example 6
(Preparation of catalyst)
In Example 1, a catalyst preparation solution was prepared by adding cupric nitrate trihydrate [Cu (NO _Three ) _Two ・ 3H _Two O] 2.44 g (10.0 mmol), ferric nitrate nonahydrate [Fe (NO _Three ) _Three ・ 9H _Two O] A catalyst was prepared in the same manner as in Example 1, except that 5.37 g (13.3 mmol) and 85% phosphoric acid 2.34 g (20 mmol) were dissolved. Table 1 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
A gas phase contact reaction was carried out in the same manner as in Example 1 except that the catalyst was changed to 8 ml of the above catalyst. Table 1 shows the results.
[0032]
Comparative Example 1
(Preparation of catalyst)
In Example 1, a catalyst preparation solution was prepared by adding ferric nitrate nonahydrate [Fe (NO _Three ) _Three ・ 9H _Two O] A catalyst was prepared in the same manner as in Example 1, except that 4.04 g (10.0 mmol) and 1.21 g (10.5 mol) of 85% phosphoric acid were dissolved. Table 1 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
A gas phase contact reaction was carried out in the same manner as in Example 1 except that the catalyst was changed to 8 ml of the above catalyst. Table 1 shows the results.
[0033]
Example 7
(Preparation of catalyst)
In Example 1, a catalyst preparation solution was prepared by adding cupric nitrate trihydrate [Cu (NO _Three ) _Two ・ 3H _Two O] 2.44 g (10.0 mmol), lanthanum nitrate hexahydrate [La (NO _Three ) _Three ・ 6H _Two [O] A catalyst was prepared in the same manner as in Example 1, except that 0.87 g (2.0 mmol) and 1.05 g (9.1 mmol) of 85% phosphoric acid were dissolved. Table 1 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
A gas phase contact reaction was carried out in the same manner as in Example 1 except that the catalyst was changed to 8 ml of the above catalyst. Table 1 shows the results.
[0034]
Example 8
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Example 4. Table 1 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
In Example 1, the catalyst was changed to 8 ml of the catalyst, the feed rate of air was changed to 80 ml / min, and the glycolic acid ester solution was replaced with water / methyl glycolate (weight ratio) = 5/95 glycolic acid ester. A gas phase contact reaction was carried out in the same manner as in Example 1 except that 6.1 g / hr of the solution was fed. Table 1 shows the results.
[0035]
Example 9
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Example 5. Table 1 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
A gas phase contact reaction was carried out in the same manner as in Example 8, except that the catalyst was changed to 8 ml of the above catalyst. Table 1 shows the results.
[0036]
[Table 1]

[0037]
Example 10
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Example 1. Table 2 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
In Example 1, a gas phase contact reaction was carried out in the same manner as in Example 1 except that the catalyst was changed to 8 ml of the above-mentioned catalyst and 5.8 g / hr of methyl glycolate was fed instead of the glycolic acid ester solution. . Table 2 shows the results.
[0038]
Comparative Example 2
(Preparation of catalyst)
In Example 1, a catalyst preparation solution was prepared by adding cupric nitrate trihydrate [Cu (NO _Three ) _Two ・ 3H _Two O] A catalyst was prepared in the same manner as in Example 1, except that the solution was changed to a solution in which 2.44 g (10.0 mmol) was dissolved. The resulting catalyst showed an X-ray diffraction spectrum of cupric oxide. Other analysis results are shown in Table 2.
(Production of methyl glyoxylate)
In Example 10, a gas phase contact reaction was carried out in the same manner as in Example 10, except that the catalyst was changed to 8 ml of the above catalyst. Table 2 shows the results.
[0039]
Example 11
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Example 2. Table 2 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
In Example 10, a gas phase contact reaction was carried out in the same manner as in Example 10, except that the catalyst was changed to 8 ml of the above catalyst. Table 2 shows the results.
[0040]
Example 12
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Example 3. Table 2 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
In Example 10, a gas phase contact reaction was carried out in the same manner as in Example 10, except that the catalyst was changed to 8 ml of the above catalyst. Table 2 shows the results.
[0041]
Example 13
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Example 4. Table 2 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
A gas phase contact reaction was carried out in the same manner as in Example 10, except that the catalyst was changed to 8 ml of the catalyst and the feed rate of air was changed to 80 ml / min. Table 2 shows the results.
[0042]
Example 14
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Example 5. Table 2 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
A gas phase contact reaction was carried out in the same manner as in Example 10 except that the catalyst was changed to 8 ml of the catalyst in Example 10, and the reaction product was analyzed. Table 2 shows the results.
[0043]
Example 15
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Example 6. Table 2 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
In Example 10, a gas phase contact reaction was carried out in the same manner as in Example 10, except that the catalyst was changed to 8 ml of the above catalyst. Table 2 shows the results.
[0044]
Comparative Example 3
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Comparative Example 1. Table 2 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
In Example 10, a gas phase contact reaction was carried out in the same manner as in Example 10, except that the catalyst was changed to 8 ml of the above catalyst. Table 2 shows the results.
[0045]
Example 16
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Example 7. Table 2 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
In Example 10, a gas phase contact reaction was carried out in the same manner as in Example 10, except that the catalyst was changed to 8 ml of the above catalyst. Table 1 shows the results.
[0046]
[Table 2]

[0047]
Example 17
(Preparation of catalyst)
In Example 5, the silicon carbide was changed to a particle size of 4 mm and a specific surface area of 1 m. ^Two The catalyst was prepared in the same manner as in Example 5, except that the amount was changed to 11.2 g / silicon carbide (TSS-99175: manufactured by Tokai High Heat Co., Ltd.) having a silica content of 0.5% by weight or less. Table 3 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
A gas phase contact reaction was carried out in the same manner as in Example 1 except that the catalyst was changed to 8 ml of the catalyst and the air feed rate was changed to 80 ml / min. Table 3 shows the results.
[0048]
Example 18
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Example 17. Table 3 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
In Example 17, a gas phase contact reaction was carried out in the same manner as in Example 17 except that the catalyst was changed to 8 ml of the above catalyst and 5.8 g / hr of methyl glycolate was fed instead of the glycolic acid ester solution. . Table 3 shows the results.
[0049]
Comparative Example 4
(Preparation of catalyst)
In Example 17, a catalyst preparation solution was prepared by adding ferric nitrate nonahydrate [Fe (NO _Three ) _Three ・ 9H _Two O] A catalyst was prepared in the same manner as in Example 17 except that 4.04 g (10.0 mmol) and 1.21 g (10.5 mol) of 85% phosphoric acid were dissolved. Table 3 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
In Example 17, the catalyst was changed to 8 ml of the above catalyst, the feed rate of air was changed to 200 ml / min, and 5.8 g / hr of methyl glycolate was fed instead of the glycolic acid ester solution. A gas phase contact reaction was carried out in the same manner as in Example 17. Table 3 shows the results.
[0050]
Example 19
(Preparation of catalyst)
In Example 5, the silicon carbide was changed to a particle size of 4 mm and a specific surface area of 1 m. ^Two The catalyst was prepared in the same manner as in Example 5, except that the amount was changed to 11.2 g / silicon carbide (TSS-90306: manufactured by Tokai High Heat Co., Ltd.) having a silica content of 7.5% by weight or less. Table 3 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
A gas phase contact reaction was carried out in the same manner as in Example 17 except that the catalyst was changed to 8 ml of the above catalyst and the feed rate of air was changed to 160 ml / min. Table 3 shows the results.
[0051]
Example 20
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Example 19. Table 3 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
A gas phase contact reaction was performed in the same manner as in Example 19, except that the catalyst was changed to 8 ml of the above catalyst and the glycolic acid ester solution was changed to a solution of acetonitrile / methyl glycolate (weight ratio) = 1. Was done. Table 3 shows the results.
[0052]
Example 21
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Example 19. Table 3 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
In Example 19, the catalyst was changed to 8 ml of the above catalyst, the air feed rate was changed to 80 ml / min, and 5.8 g / hr of methyl glycolate was fed instead of the glycolic acid ester solution. A gas phase contact reaction was carried out as in Example 19. Table 3 shows the results.
[0053]
Comparative Example 5
(Preparation of catalyst)
In Example 19, a catalyst preparation solution was prepared by adding ferric nitrate nonahydrate [Fe (NO _Three ) _Three ・ 9H _Two O] A catalyst was prepared in the same manner as in Example 16, except that 4.04 g (10.0 mmol) and 1.21 g (10.5 mmol) of 85% phosphoric acid were dissolved. Table 3 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
In Example 19, the catalyst was changed to 8 ml of the above catalyst, the feed rate of air was changed to 200 ml / min, and 5.8 g / hr of methyl glycolate was fed instead of the glycolate solution. A gas phase contact reaction was carried out as in Example 19. Table 3 shows the results.
[0054]
[Table 3]

[0055]
Example 22
(Preparation of catalyst)
In Example 5, the silicon carbide was changed to a particle diameter of 3 mm and a specific surface area of 1 m. ^Two / G or less, a catalyst was prepared in the same manner as in Example 5, except that 11.2 g of α-alumina (AL-S73: manufactured by Fujimi) having a silica content of 13% by weight was used. Table 4 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
In Example 1, the catalyst was changed to 8 ml of the catalyst, and instead of the glycolate solution, 8.3 g / hr of a glycolate solution of methanol / methyl glycolate (weight ratio) = 3/7 was fed. Performed a gas phase contact reaction in the same manner as in Example 1. Table 4 shows the results.
[0056]
Example 23
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Example 22. Table 4 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
In Example 22, a gas phase contact reaction was carried out in the same manner as in Example 22 except that the catalyst was changed to 8 ml of the above catalyst and 5.8 g / hr of methyl glycolate was fed instead of the glycolic acid ester solution. . Table 4 shows the results.
[0057]
Comparative Example 6
(Preparation of catalyst)
In Example 22, a catalyst preparation solution was prepared by adding ferric nitrate nonahydrate [Fe (NO _Three ) _Three ・ 9H _Two O] A catalyst was prepared in the same manner as in Example 22, except that 4.04 g (10.0 mmol) and 1.21 g (10.5 mmol) of 85% phosphoric acid were dissolved. Table 4 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
In Example 22, a gas phase contact reaction was carried out in the same manner as in Example 22 except that the catalyst was changed to 8 ml of the above catalyst and 5.8 g / hr of methyl glycolate was fed instead of the glycolic acid ester solution. . Table 4 shows the results.
[0058]
Example 24
(Preparation of catalyst)
In Example 5, silicon carbide was changed to a particle diameter of 4.7 mm and a specific surface area of 0.05 m. ^Two The catalyst was prepared in the same manner as in Example 5, except that α-alumina (SA-5205: manufactured by Norton) having a silica content of 12% by weight or less was used. Table 4 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
In Example 22, a gas phase contact reaction was carried out in the same manner as in Example 22 except that the catalyst was changed to 8 ml of the above catalyst. Table 4 shows the results.
[0059]
Example 25
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Example 24. Table 4 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
In Example 22, a gas phase contact reaction was carried out in the same manner as in Example 22 except that the catalyst was changed to 8 ml of the above catalyst and 5.8 g / hr of methyl glycolate was fed instead of the glycolic acid ester solution. . Table 4 shows the results.
[0060]
Comparative Example 7
(Preparation of catalyst)
In Example 24, a catalyst preparation solution was prepared by adding ferric nitrate nonahydrate [Fe (NO _Three ) _Three ・ 9H _Two [O] A catalyst was prepared in the same manner as in Example 24, except that 4.04 g (10.0 mmol) and 1.21 g (10.5 mmol) of 85% phosphoric acid were dissolved. Table 4 shows the analysis results of the obtained catalyst.
(Production of methyl glyoxylate)
In Example 22, a gas phase contact reaction was carried out in the same manner as in Example 22 except that the catalyst was changed to 8 ml of the above catalyst and 5.8 g / hr of methyl glycolate was fed instead of the glycolic acid ester solution. . Table 4 shows the results.
[0061]
[Table 4]

[0062]
Example 26
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Example 19. Table 5 shows the analysis results of the obtained catalyst. (Production of methyl pyruvate)
In Example 1, the catalyst was changed to 8 ml of the above catalyst, the feed rate of air was changed to 90 ml / min, the feed rate of nitrogen was changed to 180 ml / min, and methanol / methyl lactate (weight ratio) was used instead of the glycolic acid ester solution. ) = 5, except that 15.6 g / hr of an α-hydroxycarboxylic acid ester solution was fed, and a gas phase contact reaction was carried out in the same manner as in Example 1 to obtain methyl pyruvate as an α-ketone acid ester. . Table 5 shows the results.
[0063]
Example 27
(Preparation of catalyst)
In Example 19, a catalyst preparation solution was prepared by adding cupric nitrate trihydrate [Cu (NO _Three ) _Two ・ 3H _Two O] 3.66 g (15.0 mmol), ferric nitrate nonahydrate [Fe (NO _Three ) _Three ・ 9H _Two O] A catalyst was prepared in the same manner as in Example 19, except that the solution was changed to a solution in which 4.04 g (10.0 mmol) and 2.33 g (20.2 mmol) of 85% phosphoric acid were dissolved. Table 5 shows the analysis results of the obtained catalyst.
(Production of methyl pyruvate)
In Example 26, a gas phase contact reaction was carried out in the same manner as in Example 26 except that the catalyst was changed to 8 ml of the above catalyst, to obtain methyl pyruvate as an α-ketone ester. Table 5 shows the results.
[0064]
Example 28
(Preparation of catalyst)
In Example 19, silicon carbide was changed to a particle diameter of 4.7 mm and a specific surface area of 0.05 m. ^Two The catalyst was prepared in the same manner as in Example 19 except that α-alumina (SA-50205, manufactured by Norton) having a silica content of 11.8% by weight was used. Table 5 shows the analysis results of the obtained catalyst.
(Production of methyl pyruvate)
In Example 26, a gas phase contact reaction was carried out in the same manner as in Example 26 except that the catalyst was changed to 8 ml of the above catalyst, to obtain methyl pyruvate as an α-ketone ester. Table 5 shows the results.
[0065]
Comparative Example 8
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Comparative Example 5. Table 5 shows the analysis results of the obtained catalyst.
(Production of methyl pyruvate)
In Example 26, a gas phase contact reaction was carried out in the same manner as in Example 26 except that the catalyst was changed to 8 ml of the above catalyst, to obtain methyl pyruvate as an α-ketone ester. Table 5 shows the results.
[0066]
Example 29
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Example 19. Table 5 shows the analysis results of the obtained catalyst.
(Production of methyl phenylglyoxylate)
In Example 1, the catalyst was changed to 8 ml of the above catalyst, the feed rate of air was changed to 35 ml / min, the feed rate of nitrogen was changed to 70 ml / min, and methanol / methyl mandelate (weight) was used instead of the glycolate solution. Ratio) = 6, except that 17.0 g / hr of an α-hydroxycarboxylic acid ester solution was fed, and a gas phase contact reaction was carried out in the same manner as in Example 1 to obtain methyl phenylglyoxylate as an α-ketone acid ester. Obtained. Table 5 shows the results.
[0067]
Example 30
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Example 19. Table 5 shows the analysis results of the obtained catalyst.
(Production of methyl phenylglyoxylate)
In Example 29, except that the catalyst was changed to 8 ml of the above catalyst, the feed rate of air was changed to 56 ml / min, and the feed rate of the α-hydroxycarboxylic acid ester solution was changed to 30.7 g / hr, A gas phase contact reaction was carried out in the same manner as in Example 29 to obtain methyl phenylglyoxylate as an α-ketone acid ester. Table 5 shows the results.
[0068]
Example 31
(Preparation of catalyst)
A catalyst was prepared in the same manner as in Example 28. Table 5 shows the analysis results of the obtained catalyst.
(Production of methyl phenylglyoxylate)
In Example 29, a gas phase contact reaction was carried out in the same manner as in Example 29, except that the catalyst was changed to 8 ml of the above catalyst, to obtain methyl phenylglyoxylate as an α-ketone ester. Table 5 shows the results.
[0069]
[Table 5]

[0070]
【The invention's effect】
According to the present invention, the type of raw material, the price of the catalyst, the conversion of the raw material and the selectivity of the target product (that is, the yield of the target product), Can solve the problem concerning the production rate (space-time yield). That is, an inexpensive and highly active copper phosphate catalyst that can be easily prepared is charged into a usual reactor, and an α-hydroxycarboxylic acid ester and molecular oxygen are reacted in a gas phase to form an α-hydroxycarboxylic acid ester. With increased conversion, α-ketonates, including glyoxylates, can be produced with high selectivity (ie, high yield) and high production rates (space-time yields).

Claims (1)

A method for producing an α-ketone acid ester, comprising reacting an α-hydroxycarboxylic acid ester and molecular oxygen in a gas phase in the presence of a catalyst in which copper phosphate is supported on a carrier.