NEW NICKEL CATALYST SUPPORTED ON SILICA
The present invention relates to a new nickel (Ni) catalyst for selective hydrogena tions.
There are known many catalysts for hydrogenation. An important kind for these reac tions are the Lindlar catalysts
Lindlar catalysts are very important and well known catalysts. A Lindlar catalyst is a heterogeneous catalyst that consists of palladium deposited on calcium carbonate and treated with lead. The catalyst is used for the hydrogenation of alkynes to alkenes (i.e. without further reduction into alkanes). Thus if a compound contains a double bond as well as a triple bond, the triple bond is reduced to a double bond with high selectivity.
Lindlar catalysts are very useful and powerful catalyst, but nevertheless the replace ment of the Lindlar catalyst is desirable due to the toxicity of lead and the high cost of palladium therein.
This invention relates to the replacement of the "Lindlar catalyst” for the synthesis of vitamin and nutritional product precursors via hydrogenation of both terminal and in ternal alkynes.
The goal was to find a catalyst, which has the same properties as a classic Lindlar catalyst, but which is free of palladium and lead. Furthermore, the catalyst should be recyclable and re-usable.
Surprisingly, it was found that a new specific catalyst consisting of nickel nanoparticles and nitrogen doped carbon supported on silica has the same properties in regard to hydrogenation performance but which is free palladium-free as well as lead-free.
Therefore the present invention relates to a catalyst comprising nickel nanoparticles and nitrogen doped carbon layer, which is supported on silica
and which is palladium-free as well as lead-free.
By the terms “palladium-free” and “lead-free” in the context of the present invention it is meant that no palladium and lead is added to the catalyst system intentionally. It might be possible that such metals are present in very low traces.
The catalyst according to the present invention is produced usually (and preferably) in the following way
Step 1) a nickel ligand complex is formed which is then Step 2) deposited within the pores and onto the surface of porous silica (usually by a wet impregnation procedure), and Step 3) the reaction product of step 2) is dried and afterwards pyrolyzed (at high temperature of at least 600 °C).
Therefore, the present invention relates to a catalyst (C) obtainable by (comprising)
1) forming a nickel ligand complex;
2) depositing the nickel ligand complex of step 1) on the porous silica support (usually by a wet impregnation procedure) to form an absorbed reaction prod uct, and
3) drying and pyrolyzing (at high temperature at least 600 °C) the absorbed prod uct of step 2) to obtain the catalyst.
As a result of the process a very reactive catalyst is formed consisting of nickel nano particles and a nitrogen doped carbon layer, which is supported on silica and which is palladium-free and lead-free.
This so obtained catalyst has excellent properties in the hydrogenation of alkynes as will be shown below.
In the following, the process steps of producing the catalyst are discussed in more detail.
Step 1) (forming the nickel ligand complex)
For the formation of the nickel ligand complex at least one nickel salt is used.
Usually Ni(ll) salt(s) and/or Ni(0) salt(s) are used. The anion can be any anion. This is not crucial for the properties of the obtained catalyst.
Therefore, the present invention relates to a catalyst (C1), which is catalyst (C), wherein step 1) the at least one Ni salt is at least one Ni(ll) salt and/or at least one Ni(0) salt.
Suitable nickel salts are for example Ni(OAc)2(ac = acetyl), Ni(acac)2 (acac = acety- lacetonate), N1CO3, N1CI2, NiBr2, NiCp2 (Cp = cyclopentadienyl), (TMEDA)Ni(CH3)2 (TMEDA = Tetramethylethylenediamine), Ni(acac)2(TMEDA) and Ni(COD)2 (COD = Cyclooctadiene).
Preferred nickel salts are for example Ni(OAc)2, Ni(acac)2, N1CO3, NiBr2, NiCp2, (TMEDA)Ni(CH3)2, Ni(acac)2(TMEDA) and Ni(COD)2.
Therefore, the present invention relates to a catalyst (C2), which is catalyst (C) or (C1), wherein step 1) the at least one nickel salt is chosen from the group consisting of Ni(OAc)2, Ni(acac)2, NiCOs, NiCI2, NiBr2, NiCp2, (TMEDA)Ni(CH3)2 and Ni(COD)2.
Therefore, the present invention relates to a catalyst (C2’), which is catalyst (C) or (C1), wherein step 1) the at least one nickel salt is chosen from the group consisting of Ni(OAc)2, Ni(acac)2, NiCOs, NiCp2, (TMEDA)Ni(CH3)2, Ni(acac)2(TMEDA) and Ni(COD)2.
The ligand used in step 1) to form the nickel ligand complex can be any commonly known and used ligand. The ligand can be monodentate and/or polydentate (such as melamine, chitin, phenanthroline, 4,4-bipyridine, guanidinium chloride, terpyridine, starch, saccharose and urea). This means also a mixture of different ligands can be used. Preferred are ligands comprising at least one N atom.
Preferred ligands are chosen from the group consisting of melamine, chitin, phenan- throline, 4,4-bipyridine, guanidinium chloride, terpyridine and urea.
Therefore, the present invention relates to a catalyst (C3), which is catalyst (C), (C1) (C2) or (C2’), wherein step 1) the ligand is monodentate and/or polydentate (such as melamine, chitin, phenanthroline, 4,4-bipyridine, guanidinium chloride, terpyridine, starch, saccharose and urea).
Therefore, the present invention relates to a catalyst (C4), which is catalyst (C), (C1), (C2), (C2’) or (C3), wherein step 1) the at least one ligand comprises at least one N atom.
Therefore, the present invention relates to a catalyst (C5), which is catalyst (C), (C1), (C2), (C2’), (C3) or (C4), wherein step 1) the ligand is chosen from the group consist ing of melamine, chitin, phenanthroline, 4,4-bipyridine, guanidinium chloride, terpyri dine and urea.
The molar ratio of the nickel salts to the ligand can vary. Usually it goes from 1 :1 to 1 :15.
Preferably 1 :1 to 1:12, more preferably 1 :1 to 1:10, most preferred is a 1 :1 molar ratio.
Therefore, the present invention relates to a catalyst (C6), which is catalyst (C), (C1), (C2), (C2’), (C3), (C4) or (C5), wherein step 1) the molar ratio of the nickel salts to the ligand is from 1 :1 to 1 :15.
Preferably 1 :1 to 1 :12, more preferably 1 :1 to 1 :10 most preferred is a 1 :1 molar ratio
Therefore, the present invention relates to a catalyst (C6’), which is catalyst (C), (C1), (C2), (C2’), (C3), (C4) or (C5), wherein step 1) the molar ratio of the nickel salts to the ligand is from 1 :1 to 1 :12.
Therefore, the present invention relates to a catalyst (C6”), which is catalyst (C), (C1), (C2), (C2’), (C3), (C4) or (C5), wherein step 1) the molar ratio of the nickel salts to the ligand is from 1 :1 to 1 :10.
Therefore, the present invention relates to a catalyst (C6’”), which is catalyst (C), (C1), (C2), (C2’), (C3), (C4) or (C5), wherein step 1) the molar ratio of the nickel salts to the ligand is 1 :1.
The formation of the nickel ligand complex is usually done in at least one solvent. The nickel ligand complex should be soluble (at least partially in the solvent, which is used).
The solvents are usually polar protic or polar aprotic solvent. Suitable solvents are for example water, polar protic solvents such as alcohols, polar aprotic solvents like ke tones and esters.
Preferred solvents are chosen from the group consisting of water, methanol, ethanol, propanol, acetone, ethylene carbonate, toluene, and mixtures thereof.
Therefore, the present invention relates to a catalyst (C7), which is catalyst (C), (C1), (C2), (C2’), (C3), (C4), (C5), (C6), (C6’), (C6”) or (C6’”), wherein step 1) the formation of the nickel ligand complex is carried out in at least one solvent.
Therefore, the present invention relates to a catalyst (C7’), which is catalyst (C7), wherein the at least one solvent is a polar protic or polar aprotic solvent.
Therefore, the present invention relates to a catalyst (C7”), which is catalyst (C7), wherein the at least one solvent chosen from the group consisting of water, methanol, ethanol, propanol, acetone, ethylene carbonate and toluene.
The Ni ligand complex formation can be done at a temperature range of from 5 to 50 °C. Preferably 15 to 40 °C, more preferred is a range from 20 to 30 °C.
Therefore, the present invention relates to a catalyst (C8), which is catalyst (C), (C1), (C2), (C ), (C3), (C4), (C5), (C6), (C6’), (C6”), (C6’”), (C7), (CT) or (C7”), wherein
step 1) the formation of the nickel ligand complex is carried out a temperature range of from 5 to 50 °C.
Therefore, the present invention relates to a catalyst (C8’), which is catalyst (C), (C1), (C2), (C ), (C3), (C4), (C5), (C6), (C6’), (C6”), (C6’”), (C7), (CT) or (C7”), wherein step 1) the formation of the nickel ligand complex is carried out a temperature range of from 15 to 40 °C.
Therefore, the present invention relates to a catalyst (C8”), which is catalyst (C), (C1), (C2), (C2’), (C3), (C4), (C5), (C6), (C6’), (C6”), (C6’”), (C7), (CT) or (C7”), wherein step 1) the formation of the nickel ligand complex is carried out a temperature range of from 20 to 30 °C.
At the end the Ni ligand complex is formed.
Step 2) depositing of the nickel ligand complex
Usually the nickel ligand complex is not isolated from the reaction mixture of step 1). Usually the silica (S1O2) is added directly into the reaction mixture of step 1) after the nickel ligand complex is formed.
Preferably fumed silica is used. Fumed silica is an amorphous silica fused into branched, chainlike, three-dimensional secondary particles which then agglomerate into tertiary particles, a white powder with extremely low bulk density and thus high surface area.
Such fumed silicas are available commercially from a variety of suppliers, such as Evonik, GRACE, Palmer Holland Inc, Applied Material Solutions, AGSCO Corporation and many more.
Therefore, the present invention relates to a catalyst (C9), which is catalyst (C), (C1), (C2), (C2’), (C3), (C4), (C5), (C6), (C6’), (C6”), (C6’”), (C7), (C7’), (C7”), (C8), (C8’) or (C8”), wherein step 2) the silica used is fumed silica.
The silica is added to the reaction mixture usually in a molar excess to the Ni.
A usual amount of S1O2 added to the reaction mixture is such that the in the reaction mixture the molar ratio of Ni to S1O2 is 1 : 150 to 1 : 100, preferably 1 : 120 to 1 :80.
Therefore, the present invention relates to a catalyst (C10), which is catalyst (C), (C1), (C2), (C ), (C3), (C4), (C5), (C6), (C6’), (C6”), (C6’”), (C7), (C7’), (C7”), (C8), (C8’), (C8”) or (C9), wherein step 2) the silica is added to the reaction mixture in a molar excess to the Ni.
Therefore, the present invention relates to a catalyst (C10’), which is catalyst (C10), wherein the molar ratio of Ni to S1O2 is 1 : 150 to 1 : 100.
Therefore, the present invention relates to a catalyst (C10”), which is catalyst (C10), wherein the molar ratio of Ni to S1O2 is 1 :120 to 1 :80.
The absorption step is carried out at a temperature range of from 5 to 50 °C. Prefer ably 15 to 40 °C, more preferably 20 to 30 °C.
Therefore, the present invention relates to a catalyst (C11 ), which is catalyst (C), (C1 ), (C2), (C2’), (C3), (C4), (C5), (C6), (C6’), (C6”), (C6’”), (C7), (C7’), (C7”), (C8), (C8’), (C8”), (C9), (C10), (C10’) or (C10”), wherein step 2) the absorption step is carried out at a temperature range of from 5 to 50 °C.
Therefore, the present invention relates to a catalyst (C1 T), which is catalyst (C), (C1), (C2), (C2’), (C3), (C4), (C5), (C6), (C6’), (C6”), (C6’”), (C7), (C7’), (C7”), (C8), (C8’), (C8”), (C9), (C10), (C10’) or (C10”), wherein step 2) the absorption step is car ried out at a temperature range of from 15 to 40 °C.
Therefore, the present invention relates to a catalyst (C11 ”), which is catalyst (C), (C1), (C2), (C2’), (C3), (C4), (C5), (C6), (C6’), (C6”), (C6’”), (C7), (C7’), (C7”), (C8), (C8’), (C8”), (C9), (C10), (C10’) or (C10”), wherein step 2) the absorption step is car ried out at a temperature range of from 20 to 30 °C.
The deposited reaction product (nickel ligand complex absorbed into pores and on the surface of the porous silica) is obtained.
Step 3) drying and pyrolyzing the reaction product of step 2)
In a first step of step 3), which can be called step 3a), the solvent (or mixture of sol vents) is removed (the majority of the solvent should be removed, at least 70 wt-% of the solvent, based on the total amount of the solvent used).
Usually and preferably this is done by evaporation (usually under vacuum) of the sol vent. This is done at elevated temperature (30 - 60 °C) and under milder vacuum (30 to 200 mbar).
Therefore, the present invention relates to a catalyst (C12), which is catalyst (C), (C1), (C2), (C2’), (C3), (C4), (C5), (C6), (C6’), (C6”), (C6’”), (C7), (C7’), (C7”), (C8), (C8’), (C8”), (C9), (C10), (C10’), (C10”), (C11), (C11’) or (C11”), wherein step 3a) the sol vent (or mixture of solvents) is removed (the majority of the solvent should be re moved, at least 70 wt-% of the solvent, based on the total amount of the solvent used).
Therefore, the present invention relates to a catalyst (C12’), which is catalyst (C12), wherein step 3a) the removal of the solvent is done by evaporation (preferably at elevated temperature (30 - 60 °C) an under milder vacuum (30 to 200 mbar)).
Afterwards the so obtained reaction solid product (a powder) is usually and preferably dried under high vacuum and elevated temperature.
Therefore, the present invention relates to a catalyst (C13), which is catalyst (C), (C1), (C2), (C2’), (C3), (C4), (C5), (C6), (C6’), (C6”), (C6’”), (C7), (C7’), (C7”), (C8), (C8’), (C8”), (C9), (C10), (C10’), (C10”), (C11), (C11’), (C11”), (C12) or (C12’), wherein the reaction product of step 3a) is dried (and preferably under high vacuum and elevated temperature).
In a second step of step 3), which can be called step 3b), the obtained solid form from step 3a) is pyrolyzed.
Usually the powder obtained from step 3 a) is comminuted (i.e. by grinding) to a fine powder before the pyrolysis.
This fine powder is then pyrolysed usually in an oven (under inert atmosphere) at a temperature of at least 600 °C.
Usually at a temperature between 600 - 1200 °C (preferably at 650 to 1100 °C, more preferably 700 to 1100 °C).
Therefore, the present invention relates to a catalyst (C14), which is catalyst (C), (C1), (C2), (C ), (C3), (C4), (C5), (C6), (C6’), (C6”), (C6’”), (C7), (C7’), (C7”), (C8), (C8’), (C8”), (C9), (C10), (C10’), (C10”), (C11), (C11’), (C11”), (C12), (C12’) or (C13), wherein the reaction product of step 3a) is comminuted (i.e. by grinding) to a fine powder before the pyrolysis.
Therefore, the present invention relates to a catalyst (C15), which is catalyst (C), (C1), (C2), (C2’), (C3), (C4), (C5), (C6), (C6’), (C6”), (C6’”), (C7), (C7’), (C7”), (C8), (C8’), (C8”), (C9), (C10), (C10’), (C10”), (C11), (C11’), (C11”), (C12), (C12’), (C13) or(C14), wherein the reaction product of step 3a) is pyrolysed at a temperature of at least 600 °C.
Therefore, the present invention relates to a catalyst (C15’), which is catalyst (C), (C1), (C2), (C2’), (C3), (C4), (C5), (C6), (C6’), (C6”), (C6’”), (C7), (C7’), (C7”), (C8), (C8’), (C8”), (C9), (C10), (C10’), (C10”), (C11), (C11’), (C11”), (C12), (C12’), (C13) or (C14), wherein the reaction product of step 3a) is pyrolysed at a temperature be tween 600 - 1200 °C.
Therefore, the present invention relates to a catalyst (C15”), which is catalyst (C), (C1), (C2), (C2’), (C3), (C4), (C5), (C6), (C6’), (C6”), (C6’”), (C7), (C7’), (C7”), (C8), (C8’), (C8”), (C9), (C10), (C10’), (C10”), (C11), (C11’), (C11”), (C12), (C12’), (C13) or (C14), wherein the reaction product of step 3a) is pyrolysed at a temperature be tween 650 - 1100 °C.
Therefore, the present invention relates to a catalyst (C15’”), which is catalyst (C), (C1), (C2), (C ), (C3), (C4), (C5), (C6), (C6’), (C6”), (C6’”), (C7), (C7’), (C7”), (C8), (C8’), (C8”), (C9), (C10), (C10’), (C10”), (C11), (C11’), (C11”), (C12), (C12’), (C13) or (C14), wherein the reaction product of step 3a) is pyrolysed at a temperature be tween 700 - 1100 °C.
The duration of the pyrolysis is usually between 1 and 10 hours.
Therefore, the present invention relates to a catalyst (C16), which is catalyst (C), (C1), (C2), (C2’), (C3), (C4), (C5), (C6), (C6’), (C6”), (C6’”), (C7), (C7’), (C7”), (C8), (C8’), (C8”), (C9), (C10), (C10’), (C10”), (C11), (C11’), (C11”), (C12), (C12’), (C13), (C14), (C15), (C15’), (C15”) or (C15”’), wherein step 3b) the duration of the pyrolysis is be tween 1 and 10 hours.
At the end of this process the catalyst is obtained as a powder (powderous catalyst).
Furthermore, the present invention relates to a catalyst made by the process steps as defined and disclosed above.
The carbon content, the hydrogen content, the nitrogen content and the nickel content of the powderous catalysts obtained by the process as described above can be de termined by elemental analysis.
The values of these contents vary depending on the amount of the various ingredients (such as Ni salt, ligand) as well as on the pyrolysis conditions (temperature and dura tion).
Typical values are for
C : 0.5 to 5 wt-%, based on the total weight of the powderous catalyst H : 0.01 to 2 wt-%, based on the total weight of the powderous catalyst N : 0.05 to 2 wt-%, based on the total weight of the powderous catalyst Ni : 1.5 to 6 wt-%, based on the total weight of the powderous catalyst.
Therefore the present invention relates to a catalyst comprising
nickel nanoparticles and nitrogen doped carbon layer, which is supported on silica and which is free from palladium as well as free from lead and comprising C : 0.5 to 5 wt-%, based on the total weight of the powderous catalyst, and H : 0.01 to 2 wt-%, based on the total weight of the powderous catalyst, and N : 0.05 to 2 wt-%, based on the total weight of the powderous catalyst, and Ni : 1.5 to 6 wt-%, based on the total weight of the powderous catalyst.
The rest of the 100 % is the silica.
The so produced powderous Ni catalyst is used as a catalyst in hydrogenation reac tions, especially in selective hydrogenations. The catalyst is used for the hydrogena tion of alkynes to alkenes (i.e. without further reduction into alkanes).
Therefore, the present invention relates to a hydrogenation (H), wherein at least one catalyst (C), (C1), (C2), (C ), (C3), (C4), (C5), (C6), (C6’), (C6”), (C6’”), (C7), (C7’), (C7”), (C8), (C8’), (C8”), (C9), (C10), (C10’), (C10”), (C11), (C1 f), (C11”), (C12), (C12’), (C13), (C14), (C15), (C15’), (C15”) and/or (C15’”) is used.
Therefore, the present invention relates to a hydrogenation (H1), which is hydrogena tion (H), wherein the hydrogenation is a selective hydrogenation.
Therefore, the present invention relates to a hydrogenation (H2), which is hydrogena tion (H) or (H1), wherein the hydrogenation of alkynes to alkenes.
Preferred compound, which are hydrogenated selectively, are those of formula (I)
R = Ri (I) wherein
R is H; linear or branched, or cyclic Ci - C20 alkyl, which can be substituted by OH, NH, NH2, C(O) and/or aromatic alkynes; or linear or branched, or cyclic C2-
C20 alkylene, which can be substituted by OH, NH, NH2, C(O) and/or aromatic alkynes, and
Ri is linear or branched, or cyclic C3 - C45 alkyl, which can be substituted by OH, NH, NH2, C(O), aromatic alkynes; linear or branched or cyclic C3 - C45 alkylene, which can be substituted by OH, NH, NH2, C(O), aromatic alkynes.
The use of the catalyst of the present invention allows hydrogenation of compounds of formula (I) to the corresponding alkene compound of formula (G)
R-=-R (G) wherein R and R1 have the same meanings are defined for the compound of formula (I).
Therefore, the present invention relates to a hydrogenation (H3), which is hydrogen ated to (H), (H1) or (H2), wherein compounds of formula (I)
R = Ri (I) wherein
R is H; linear or branched, or cyclic Ci - C20 alkyl, which can be substituted by OH, NH, NH2, C(O) and/or aromatic alkynes; or linear or branched, or cyclic C2- C20 alkylene, which can be substituted by OH, NH, NH2, C(O) and/or aromatic alkynes, and
Ri is linear or branched, or cyclic C3 - C45 alkyl, which can be substituted by OH, NH, NH2, C(O), aromatic alkynes; linear or branched or cyclic C3 - C45 alkylene, which can be substituted by OH, NH, NH2, C(O), aromatic alkynes, are hydrogenated selectively.
Preferred compounds are those of formula (I), wherein R is H, and
Ri is linear or branched, or cyclic C3 - C45 alkyl, which can be substituted by OH; linear or branched C3 - C45 alkylene, which can be substituted by OH.
More preferred compounds are those of formula (I), wherein R is H, and
Ri is linear or branched, or cyclic C3 - C20 alkyl, which can be substituted by OH; linear or branched C3 - C20 alkylene, which can be substituted by OH.
Most preferred are the compounds of formula (la), (lb) and (lc)
Therefore, the present invention relates to a hydrogenation (H3’), which is hydrogena tion (H3), wherein R is H, and
R1 is linear or branched, or cyclic C3 - C45 alkyl, which can be substituted by OH; linear or branched C3 - C45 alkylene, which can be substituted by OH.
Therefore, the present invention relates to a hydrogenation (H3”), which is hydro genation (H3), wherein R is H, and
Ri is linear or branched, or cyclic C3 - C20 alkyl, which can be substituted by OH; linear or branched C3 - C20 alkylene, which can be substituted by OH.
Therefore, the present invention relates to a hydrogenation (H3’”), which is hydro genation (H3), wherein the compound of formula (la)
Therefore, the present invention relates to a hydrogenation (H3””), which is hydro genation (H3), wherein the compound of formula (lb)
Therefore, the present invention relates to a hydrogenation (H3’””), which is hydro- genation (H3), wherein the compound of formula (lc)
The hydrogenation using the catalyst according to the present invention is usually carried out in at least one solvent.
When using solvents then suitable solvents are acetonitrile, ethanol and propanol.
It is also possible to carry out the hydrogenation without any solvents.
Therefore, the present invention relates to a hydrogenation (H4), which is hydrogena tion (H), (H1), (H2), (H3), (H3’), (H3”), (H3’”), (H3””) or(H3””’), wherein hydrogenation is carried out in at least one solvent.
Therefore, the present invention relates to a hydrogenation (H4’), which is hydrogena tion (H4), wherein the at least one solvent is chosen from the group consisting of acetonitrile, ethanol and propanol.
Therefore, the present invention relates to a hydrogenation (H5), which is hydrogena tion (H), (H1), (H2), (H3), (H3’), (H3”), (H3’”), (H3””) or(H3””’), wherein hydrogenation is carried out without any solvent.
The hydrogenation according to the present invention is usually carried out at elevated temperatures.
Usually it is carried out at a temperature between 15 - 150 °C. preferably 20 to 140 °C.
Therefore, the present invention relates to a hydrogenation (H6), which is hydrogena tion (H), (H1), (H2), (H3), (H3’), (H3”), (H3’”), (H3””), (H3’””), (H4), (H4’) or (H5), wherein hydrogenation is carried out at elevated temperatures.
Therefore, the present invention relates to a hydrogenation (H6’), which is hydrogena tion (H6), wherein hydrogenation is carried out at a temperature between 15 - 150 °C.
Therefore, the present invention relates to a hydrogenation (H6”), which is hydro genation (H6), wherein hydrogenation is carried out at a temperature between 20 to 140 °C.
The hydrogenation according to the present invention is carried by using H2 gas (pure or as a mixture). Preferably pure H2 gas is used.
Therefore, the present invention relates to a hydrogenation (H7), which is hydrogena tion (H), (H 1 ), (H2), (H3), (H3’), (H3”), (H3’”), (H3””), (H3’””), (H4), (H4’), (H5), (H6), (H6’) or (H6”), wherein H2 gas (pure or as a mixture) is used (preferably pure H2 gas).
The hydrogenation according to the present invention is carried out at elevated pres sure. Usually the absolute pressure used is between 1 and 50 bar, preferably between 1 and 40 bar.
Therefore, the present invention relates to a hydrogenation (H8), which is hydrogena tion (H), (H1), (H2), (H3), (H3’), (H3”), (H3’”), (H3””), (H3’””), (H4), (H4’), (H5), (H6), (H6’), (H6”) or (H7), wherein the hydrogenation is carried out at elevated pressure.
Therefore, the present invention relates to a hydrogenation (H8’), which is hydrogena tion (H8), wherein the hydrogenation is carried out at an absolute pressure between 1 and 50 bar.
Therefore, the present invention relates to a hydrogenation (H8”), which is hydro genation (H8), wherein the hydrogenation is carried out at an absolute pressure be tween 1 and 40 bar.
The amount of the catalyst used in the hydrogenation according to the present inven tion is between 0.1 - 5 mol-% (in view of the compound to the hydrogenated). Prefer ably 0.5 - 4 mol-%.
Therefore, the present invention relates to a hydrogenation (H9), which is hydrogena tion (H), (H 1 ), (H2), (H3), (H3’), (H3”), (H3’”), (H3””), (H3’””), (H4), (H4’), (H5), (H6), (H6’), (H6”), (H7), (H8), (H8’) or (H8”), wherein the catalyst is used in an amount between 0.1 - 5 mol-% (in view of the compound to the hydrogenated).
Therefore, the present invention relates to a hydrogenation (H9’), which is hydrogena tion (H), (H 1 ), (H2), (H3), (H3’), (H3”), (H3’”), (H3””), (H3’””), (H4), (H4’), (H5), (H6), (H6’), (H6”), (H7), (H8), (H8’) or (H8”), wherein the catalyst is used in an amount between 0.5 - 4 mol-% (in view of the compound to the hydrogenated).
A further advantage of the catalyst according to the present invention is that it can be recycled and reused, and the activity of the catalyst stays on a similar level.
The hydrogenation can be carried out batch-wise or continuously.
Therefore, the present invention relates to a hydrogenation (H10), which is hydro genation (H), (H1), (H2), (H3), (H3’), (H3”), (H3’”), (H3””), (H3’””), (H4), (H4’), (H5), (H6), (H6’), (H6”), (H7), (H8), (H8’), (H8”), (H9) or (H9’), wherein the hydrogenation is carried out batch-wise.
Therefore, the present invention relates to a hydrogenation (H11), which is hydro genation (H), (H1), (H2), (H3), (H3’), (H3”), (H3’”), (H3””), (H3’””), (H4), (H4’), (H5), (H6), (H6’), (H6”), (H7), (H8), (H8’), (H8”), (H9) or (H9’), wherein the hydrogenation is carried out continuously.
The following examples serve to illustrate the invention. If not otherwise stated all parts given are related to the weight and the temperature is given in °C.
Examples
Example 1 : Catalyst Synthesis In a 250 mL round bottomed flask Ni(0Ac)2.4H20 (0.27 g, 1.10 mmol), melamine (0.14 g, 1.10 mmol), EtOH (45 mL) and distilled water (1.5 mL) were stirred at room temperature for 15 mins. A pale green solution with some suspended melamine formed. The flask was placed in an oil bath pre-heated to 60 °C and stirred for 1 h. Some melamine remained undissolved. S1O2 (Aerosil 0X50, 1.61 g) was added so that the Ni was ca. 4 wt. % relative to S1O2. The suspension was stirred at RT over night (22 h). Solvent was removed via rotary evaporation (45 °C, 80 mbar) to leave a pale green powder which was dried overnight (19 h) at RT under high vacuum. The dry solid was ground to a fine powder and 0.534 g was placed in a ceramic crucible with a lid. The crucible was placed in an oven which was evacuated to ca. 5 mbar and then flushed with argon. The oven was heated to 800 °C with a heating rate of 25 °C/min. The oven was held at the final temperature for 2 h, purging with argon the entire time. The oven was allowed to cool to room temperature, the crucible re moved, and the catalyst (0.456 g, 85 % yield) transferred to a sample vial for stor age. The catalyst synthesis has also been demonstrated with a molar ratio of metal pre cursor to melamine of 1 :5, 1 :10. All catalysts ratios were pyrolyzed at 800 °C and 1000 °C. The procedure was the same for catalysts pyrolyzed at 1000 °C except the final oven temperature was 1000 °C. The following table (Table 1) shows the elemental analysis of the catalysts of the examples.
Table 1 : Elemental analysis of the prepared catalysts.
Hydrogenation Examples
Reduction of 3,7,11,15-tetramethylhexadec-1-yn-3-ol to isophytol using the catalyst 1 - 6 of Table 1 General Procedure
The catalytic activity tests were performed in a 300 ml autoclave advanced with an internal aluminium plate to include eight uniform reaction glass vials (4 ml) with cap, septum, and needle. 3,7,11 ,15-tetramethylhexadec-1-yn-3-ol (0.25 mmol), nickel cat alyst (1 mol %) and MeCN (2 mL) were placed in a 4 ml_ vial. A cap with a septum punctured by a needle, to allow entry of H2, was fitted. The vial was placed in an aluminium plate which was inserted into a 300 mL stainless steel autoclave. The au toclave was sealed and flushed twice with H2 (10 bar below the required pressure, or 5 bar for reactions performed with 5 bar H2) and then charged with the required H2 pressure. The autoclave was placed in an aluminium block pre-heated to the reaction temperature and maintained at this temperature for the desired time, with a stir rate of 750 ppm. Following the reaction, the autoclave was cooled in an ice-water bath and the pressure released. Dodecane (40 pL) was added as internal standard and the reaction mixture diluted with chloroform (1 mL). The catalyst and reaction mixture were separated via centrifugation (5000 RPM, 2 minutes). The recovered catalyst was washed with ethyl acetate (3 x 4 mL), separating via centrifugation as before, and then dried under high vacuum for ca. 22 h. The reaction mixture was filtered through a celite plug and the product composition analysed via GC.
Table 2: The activity and selectivity of the Ni catalysts (of Table 1) at elevated H2 pressure (30 bar) for 2 h.
Hydrogenation conditions: Substrate 0.25 mmol, Ni catalyst (1 mol %), MeCN (2 mL), (120 °C, stir rate 750 RPM, 30 bar H2, 2 h).
Table 3: The activity and selectivity of the Ni catalysts (of Table 1) at low H2 pressure (5 bar) for 15 h.
Conditions: Substrate 0.25 mmol, Ni catalyst (1 mol %), MeCN (2 mL), (120 °C, stir rate 750 RPM, 5 bar H2, 15 h).
Table 4: The activity and selectivity of the Ni catalysts (of Table 1) when EtOH is the reaction solvent.
Conditions: Substrate 0.25 mmol, Ni catalyst (1 mol %), EtOH (2 mL), (120 °C, stir rate 750 RPM, 5 bar H2, 15 h).
Table 5: The activity and selectivity of the Ni catalysts (of Table 1) when heptane is the reaction solvent.
Conditions: Substrate 0.25 mmol, Ni catalyst (1 mol %), heptane (2 mL), (120 °C, stir rate 750 RPM, 5 bar H2, 15 h).
Reduction of MBY (2-methyl-3-butyn-2-ol) to MBE (2-methyl-3-buten-2-ol) using the catalyst 1 - 6 of Table 1
General Procedure
The catalytic activity tests are performed in a 300 ml autoclave advanced with an internal aluminium plate to include eight uniform reaction glass vials (4 ml) with cap, septum, and needle. MBY (0.25 mmol), nickel catalyst (1 mol %) and MeCN (2 mL) are placed in a 4 mL vial. A cap with a septum punctured by a needle, to allow entry of H2, is fitted. The vial is placed in an aluminium plate which is inserted into a 300 mL stainless steel autoclave. The autoclave is sealed and flushed twice with H2 (10 bar below the required pressure, or 5 bar for reactions performed with 5 bar H2) and then charged with the required H2 pressure. The autoclave is placed in an aluminium block pre-heated to the reaction temperature and maintained at this temperature for the desired time, with a stir rate of 750 ppm. Following the reaction, the autoclave is cooled in an ice-water bath and the pressure released. Dodecane (40 pL) is added as internal standard and the reaction mixture diluted with chloroform (1 mL). The catalyst and reaction mixture are separated via centrifugation (5000 RPM, 2 minutes). The recovered catalyst is washed with ethyl acetate (3 x 4 mL), separating via centrifuga tion as before, and then dried under high vacuum for ca. 22 h. The reaction mixture is filtered through a celite plug and the product composition analysed via GC. MBE is obtained in good yields.
Reduction of DLL (Dehydrolinalool) to Linalool using the catalyst 1 - 6 of Table 1
General Procedure
The catalytic activity tests are performed in a 300 ml autoclave advanced with an internal aluminium plate to include eight uniform reaction glass vials (4 ml) with cap, septum, and needle. Dehydrolinalool (0.25 mmol), nickel catalyst (1 mol %) and MeCN (2 mL) are placed in a 4 mL vial. A cap with a septum punctured by a needle, to allow entry of H2, is fitted. The vial is placed in an aluminium plate which is inserted into a 300 mL stainless steel autoclave. The autoclave is sealed and flushed twice with H2 (10 bar below the required pressure, or 5 bar for reactions performed with 5
bar H2) and then charged with the required H2 pressure. The autoclave is placed in an aluminium block pre-heated to the reaction temperature and maintained at this tem perature for the desired time, with a stir rate of 750 ppm. Following the reaction, the autoclave is cooled in an ice-water bath and the pressure released. Dodecane (40 pl_) is added as internal standard and the reaction mixture diluted with chloroform (1 ml_). The catalyst and reaction mixture are separated via centrifugation (5000 RPM, 2 minutes). The recovered catalyst is washed with ethyl acetate (3 x 4 ml_), separating via centrifugation as before, and then dried under high vacuum for ca. 22 h. The re action mixture is filtered through a celite plug and the product composition analysed via GC.
Linalool is obtained in good yields.