Heterocycle Catalyzed Electrochemical Process

Abstract

A method for heterocycle catalyzed electrochemical reduction of a carbonyl compound is disclosed. The method generally includes steps (A) to (C). Step (A) may introduce the carbonyl compound into a solution of an electrolyte and a heterocycle catalyst in a divided electrochemical cell. The divided electrochemical cell may include an anode in a first cell compartment and a cathode in a second cell compartment. The cathode generally reduces the carbonyl compound to at least one aldehyde compound. Step (B) may vary which of the aldehyde compounds is produced by adjusting one or more of (i) a cathode material, (ii) the electrolyte, (iii) the heterocycle catalyst, (iv) a pH level and (v) an electrical potential. Step (C) may separate the aldehyde compounds from the solution.

What is claimed is: 
     
         1 . A method for heterocycle catalyzed electrochemical reduction of a carbonyl compound, comprising the steps of:
 (A) introducing said carbonyl compound into a solution of an electrolyte and a heterocycle catalyst in a divided electrochemical cell, wherein (i) said divided electrochemical cell comprises an anode in a first cell compartment and a cathode in a second cell compartment, (ii) said cathode reducing said carbonyl compound to at least one aldehyde compound;   (B) varying which of said aldehyde compounds is produced by adjusting one or more of (i) a cathode material, (ii) said electrolyte, (iii) said heterocycle catalyst, (iv) a pH level and (v) an electrical potential; and   (C) separating said aldehyde compounds from said solution.   
     
     
         2 . The method according to  claim 1 , wherein said cathode material is at least one of Al, Au, Ag, C, Cd, Co, Cr, Cu, Cu alloys, Ga, Hg, In, Mo, Nb, Ni, Ni alloys, Ni—Fe alloys, Sn, Sn alloys, Ti, V, W, Zn, elgiloy, Nichrome, austenitic steel, duplex steel, ferritic steel, martensitic steel, stainless steel, degenerately doped p-Si, degenerately doped p-Si:As and degenerately doped p-Si:B. 
     
     
         3 . The method according to  claim 1 , wherein said electrolyte is at least one of Na 2 SO 4 , KCl, NaNO 3 , NaCl, NaF, NaClO 4 , KClO 4 , K 2 SiO 3 , CaCl 2 , a H cation, a Li cation, a Na cation, a K cation, a Rb cation, a Cs cation, a Ca cation, an ammonium cation, an alkylammonium cation, a F anion, a Cl anion, a Br anion, an I anion, an At anion, an alkyl amine, borates, carbonates, nitrites, nitrates, phosphates, polyphosphates, perchlorates, silicates, sulfates, and a tetraalkyl ammonium salt. 
     
     
         4 . The method according to  claim 1 , wherein said heterocycle catalyst is one or more of amino-thiazole, aromatic heterocyclic amines with an aromatic 5-member heterocyclic ring, aromatic heterocyclic amines with 6-member heterocyclic ring, azoles, benzimidazole, bipyridines, furan, imidazoles, imidazole related species with at least one five-member ring, indoles, pyridines, pyridine related species with at least one six-member ring, pyrrole, thiophene and thiazoles. 
     
     
         5 . The method according to  claim 1 , wherein said pH level ranges from approximately 3 to approximately 8. 
     
     
         6 . The method according to  claim 1 , wherein said electrical potential ranges from approximately −1 volt to approximately −2 volts. 
     
     
         7 . The method according to  claim 1 , wherein said aldehyde compounds comprise one or more of benzaldehyde, butanal, formaldehyde and glyoxal. 
     
     
         8 . A method for heterocycle catalyzed electrochemical reduction of an aldehyde compound, comprising the steps of: (A) introducing said aldehyde compound into a solution of an electrolyte and a heterocycle catalyst in a divided electrochemical cell, wherein (i) said divided electrochemical cell comprises an anode in a first cell compartment and a cathode in a second cell compartment, (ii) said cathode reducing said aldehyde compound to at least one alcohol; (B) varying which of said alcohols is produced by adjusting one or more of (i) a cathode material, (ii) said electrolyte, (iii) said heterocycle catalyst, (iv) a pH level and (v) an electrical potential; and (C) separating said alcohol from said solution. 
     
     
         9 . The method according to  claim 8 , wherein said cathode material is at least one of Al, Au, Ag, C, Cd, Co, Cr, Cu, Cu alloys, Ga, Hg, In, Mo, Nb, Ni, Ni alloys, Ni—Fe alloys, Sn, Sn alloys, Ti, V, W, Zn, elgiloy, Nichrome, austenitic steel, duplex steel, ferritic steel, martensitic steel, stainless steel, degenerately doped p-Si, degenerately doped p-Si:As and degenerately doped p-Si:B. 
     
     
         10 . The method according to  claim 8 , wherein said electrolyte is at least one of Na.sub.2SO.sub.4, KCl, NaNO.sub.3, NaCl, NaF, NaClO, KClO.sub.4, K.sub.2SiO.sub.3, CaCl.sub.2, a H cation, a Li cation, a Na cation, a K cation, a Rb cation, a Cs cation, a Ca cation, an ammonium cation, an alkylammonium cation, a F anion, a Cl anion, a Br anion, an I anion, an At anion, an alkyl amine, borates, carbonates, nitrites, nitrates, phosphates, polyphosphates, perchlorates, silicates, sulfates, and a tetraalkyl ammonium salt. 
     
     
         11 . The method according to  claim 8 , wherein said heterocycle catalyst is one or more of amino-thiazole, aromatic heterocyclic amines with an aromatic 5-member heterocyclic ring, aromatic heterocyclic amines with 6-member heterocyclic ring, azoles, benzimidazole, bipyridines, furan, imidazoles, imidazole related species with at least one five-member ring, indoles, pyridines, pyridine related species with at least one six-member ring, pyrrole, thiophene and thiazoles. 
     
     
         12 . The method according to  claim 8 , wherein said alcohol comprises one or more of 2-butanol, n-butanol, ethanol, methanol, propanol and propioin. 
     
     
         13 . The method according to  claim 8 , wherein said cathode further reduces a keto compound to at least one hydroxyl compound. 
     
     
         14 . The method according to  claim 8 , wherein said reducing is performed at ambient temperature and ambient pressure. 
     
     
         15 . The method according to  claim 8 , wherein a faradaic yield of said alcohol is at least 50 percent. 
     
     
         16 . A method for heterocycle catalyzed hydrodimerization of carbonyl-containing molecules, comprising the steps of: (A) introducing said carbonyl-containing molecules into a solution of an electrolyte and a heterocycle catalyst in a divided electrochemical cell, wherein (i) said divided electrochemical cell comprises an anode in a first cell compartment and a cathode in a second cell compartment, (ii) said cathode hydrodimerizing said carbonyl-containing molecules into at least one organic product; (B) varying which of said organic products is produced by adjusting one or more of (i) a cathode material, (ii) said electrolyte, (iii) said heterocycle catalyst, (iv) a pH level and (v) an electrical potential; and (C) separating said organic products from said solution. 
     
     
         17 . The method according to  claim 16 , wherein said electrolyte is at least one of Na.sub.2SO.sub.4, KCl, NaNO.sub.3, NaCl, NaF, NaClO.sub.4, KClO.sub.4, K.sub.2SiO.sub.3, CaCl.sub.2, a H cation, a L1 cation, a Na cation, a K cation, a Rb cation, a Cs cation, a Ca cation, an ammonium cation, an alkylammonium cation, a F anion, a Cl anion, a Br anion, an I anion, an At anion, an alkyl amine, borates, carbonates, nitrites, nitrates, phosphates, polyphosphates, perchlorates, silicates, sulfates, and a tetraalkyl ammonium salt. 
     
     
         18 . The method according to  claim 16 , wherein said heterocycle catalyst is one or more of amino-thiazole, aromatic heterocyclic amines with an aromatic 5-member heterocyclic ring, aromatic heterocyclic amines with 6-member heterocyclic ring, azoles, benzimidazole, bipyridines, furan, imidazoles, imidazole related species with at least one five-member ring, indoles, pyridines, pyridine related species with at least one six-member ring, pyrrole, thiophene and thiazoles. 
     
     
         19 . The method according to  claim 16 , wherein said organic products comprise one or more of butanone, butanol, octanone and octanol. 
     
     
         20 . The method according to  claim 16 , wherein said carbonyl-containing molecules comprise one or more of acetaldehyde, butyric acid and lactic acid. 
     
     
         21 . A method for heterocycle catalyzed electrochemical reduction of a carbonyl compound, comprising the steps of:
 (A) introducing a carboxylic acid into a solution of an electrolyte and a heterocycle catalyst in a divided electrochemical cell, wherein (i) said divided electrochemical cell comprises an anode in a first cell compartment and a cathode in a second cell compartment, (ii) said cathode reducing said carboxylic acid to at least one aldehyde compound;   (B) varying which of said aldehyde compounds is produced by adjusting one or more of (i) a cathode material, (ii) said electrolyte, (iii) said heterocycle catalyst, (iv) a pH level and (v) an electrical potential; and   (C) separating said aldehyde compounds from said solution.   
     
     
         22 . The method according to  claim 21 , wherein said cathode material is at least one of Al, Au, Ag, C, Cd, Co, Cr, Cu, Cu alloys, Ga, Hg, In, Mo, Nb, Ni, Ni alloys, Ni—Fe alloys, Sn, Sn alloys, Ti, V, W, Zn, elgiloy, Nichrome, austenitic steel, duplex steel, ferritic steel, martensitic steel, stainless steel, degenerately doped p-Si, degenerately doped p-Si:As and degenerately doped p-Si:B. 
     
     
         23 . The method according to  claim 21 , wherein said electrolyte is at least one of Na 2 SO 4 , KCl, NaNO 3 , NaCl, NaF, NaClO 4 , KClO 4 , K 2 SiO 3 , CaCl 2 , a H cation, a Li cation, a Na cation, a K cation, a Rb cation, a Cs cation, a Ca cation, an ammonium cation, an alkylammonium cation, a F anion, a Cl anion, a Br anion, an I anion, an At anion, an alkyl amine, borates, carbonates, nitrites, nitrates, phosphates, polyphosphates, perchlorates, silicates, sulfates, and a tetraalkyl ammonium salt. 
     
     
         24 . The method according to  claim 21 , wherein said heterocycle catalyst is one or more of amino-thiazole, aromatic heterocyclic amines with an aromatic 5-member heterocyclic ring, aromatic heterocyclic amines with 6-member heterocyclic ring, azoles, benzimidazole, bipyridines, furan, imidazoles, imidazole related species with at least one five-member ring, indoles, pyridines, pyridine related species with at least one six-member ring, pyrrole, thiophene and thiazoles. 
     
     
         25 . The method according to  claim 21 , wherein said pH level ranges from approximately 3 to approximately 8. 
     
     
         26 . The method according to  claim 21 , wherein said electrical potential ranges from approximately −1 volt to approximately −2 volts. 
     
     
         27 . The method according to  claim 21 , wherein said aldehyde compounds comprise one or more of benzaldehyde, butanal, formaldehyde and glyoxal. 
     
     
         28 . A method electrochemical reduction of a carbonyl compound, comprising the steps of:
 (A) introducing a carbonyl compound into a solution of an electrolyte in a first divided electrochemical cell, wherein (i) said first divided electrochemical cell comprises an anode in a first cell compartment and a cathode in a second cell compartment, (ii) said cathode reducing said carbonyl compound to oxalic acid;   (B) separating the oxalic acid from the solution of said first divided electrochemical cell;   (C) introducing the oxalic acid into a solution of an electrolyte in a second divided electrochemical cell, wherein (i) said second divided electrochemical cell comprises an anode in a first cell compartment and a cathode in a second cell compartment, (ii) said cathode reducing said oxalic acid to acetic acid; and   (D) separating said acetic acid from said solution of said second divided electrochemical cell.   
     
     
         29 . The method as claimed in  claim 28 , wherein the cathode of the second divided electrochemical cell is stainless steel. 
     
     
         30 . The method as claimed in  claim 29 , wherein the solution of an electrolyte includes a homogeneous catalyst. 
     
     
         31 . The method as claimed in  claim 30 , wherein the homogeneous catalyst is 2,6 lutidine. 
     
     
         32 . A method electrochemical reduction of a carbonyl compound, comprising the steps of:
 (A) introducing a carbonyl compound into a solution of an electrolyte in a first divided electrochemical cell, wherein (i) said first divided electrochemical cell comprises an anode in a first cell compartment and a cathode in a second cell compartment, (ii) said cathode reducing said carbonyl compound to glyoxal;   (B) separating the glyoxal from the solution of said first divided electrochemical cell;   (C) introducing the glyoxal into a solution of an electrolyte in a second divided electrochemical cell, wherein (i) said second divided electrochemical cell comprises an anode in a first cell compartment and a cathode in a second cell compartment, (ii) said cathode reducing said glyoxal to glycolaldehyde;   (D) separating the glycolaldehyde from the solution of said second divided electrochemical cell.   
     
     
         33 . The method as claimed in  claim 32 , wherein the cathode of the second divided electrochemical cell is indium. 
     
     
         34 . The method as claimed in  claim 33 , wherein the solution of an electrolyte includes a homogeneous catalyst.