The present invention relates to a new cobalt (Co) 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 cobalt nanoparti cles 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 cobalt 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 cobalt 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 cobalt ligand complex;

2) depositing the cobalt 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 cobalt na noparticles and a cobalt 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 cobalt ligand complex)

For the formation of the cobalt ligand complex at least one cobalt salt is used.

Usually Co(ll) salt(s), Co(l) salt(s) and/or Co(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) at least one Co salt is at least one Co(ll) salt and/or at least one Co(l) salt and/or at least one Co(0) salt.

Suitable cobalt salts are for example Co(OAc) ₂ (Ac = acetyl), Co(acac) ₂ (acac = acet- ylacetonate), C0CO3, C0CI2, CoBr2, C0CP2 (Cp = cyclopentadienyl), (TMEDA)CO(CH ₃ ) ₂ (TMEDA = Tetramethylethylenediamine), Co(acac) ₂ (TMEDA) and CO(COD) ₂ (COD = Cyclooctadiene).

Preferred cobalt salts are for example Co(OAc) ₂ , Co(acac) ₂ , C0CO ₃ , C0CP ₂ , (TMEDA)CO(CH ₃ ) ₂ , Co(acac) ₂ (TMEDA) and Co(COD) ₂ .

Therefore, the present invention relates to a catalyst (C2), which is catalyst (C) or (C1), wherein step 1) at least one cobalt salt is chosen from the group consisting of CO(OAC) ₂ , Co(acac) ₂ , C0CO3, C0CI2, CoBr _2, C0CP2, (TMEDA)Co(CH ₃ )2 and CO(COD) ₂ .

Therefore, the present invention relates to a catalyst (C2’), which is catalyst (C) or (C1), wherein step 1) at least one cobalt salt is chosen from the group consisting of CO(OAC)2, Co(acac)2, C0CO3, C0CP2, (TMEDA)Co(CH3)2, Co(acac)2(TMEDA) and CO(COD) ₂ .

The ligand used in step 1) to form the cobalt 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-biperidine, 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) 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 cobalt 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 cobalt 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 cobalt 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 cobalt 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 cobalt salts to the ligand is 1 :1.

The formation of the cobalt ligand complex is usually done in at least one solvent. The cobalt 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 cobalt ligand complex is carried out in at least one solvent.

Therefore, the present invention relates to a catalyst (C7’), which is catalyst (C7), wherein 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 at least one solvent chosen from the group consisting of water, methanol, ethanol, propanol, acetone, ethylene carbonate and toluene.

The Co 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), (C7’) or (C7”), wherein step 1 ) the formation of the cobalt 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), (C7’) or (C7”), wherein step 1 ) the formation of the cobalt 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), (C7’) or (C7”), wherein step 1 ) the formation of the cobalt ligand complex is carried out a temperature range of from 20 to 30 °C.

At the end the Co ligand complex is formed.

Step 2) depositing of the cobalt ligand complex

Usually the cobalt 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 cobalt 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 Co.

A usual amount of S1O2 added to the reaction mixture is such that the in the reaction mixture the molar ratio of Co 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 Co.

Therefore, the present invention relates to a catalyst (C10’), which is catalyst (C10), wherein the molar ratio of Co 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 Co 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 (cobalt 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), (C2’), (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), (C ), (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 cobalt 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 Co salt, ligand) as well as on the pyrolysis conditions (temperature and du ration).

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 : 0.02 to 2 wt-%, based on the total weight of the powderous catalyst Co : 2 to 7 wt-%, based on the total weight of the powderous catalyst.

Therefore the present invention relates to a catalyst comprising cobalt 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 : 0.02 to 2 wt-%, based on the total weight of the powderous catalyst, and Co : 2 to 7 wt-%, based on the total weight of the powderous catalyst.

The rest of the 100 % is the silica.

The so produced powderous Co 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), (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”) 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) 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 C ₃ - C ₄₅ alkyl, which can be substituted by OH, NH, NH ₂ , C(O), aromatic alkynes; linear or branched or cyclic C ₃ - C ₄₅ alkylene, which can be substituted by OH, NH, NH ₂ , C(O), aromatic alkynes.

The use of the catalyst of the present invention allows hydrogenation of the com pounds of formula (I) to the corresponding alkene compound of formula (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) (I) wherein

R is H; linear or branched, or cyclic Ci - C ₂₀ alkyl, which can be substituted by OH, NH, NH ₂ , C(O) and/or aromatic alkynes; or linear or branched, or cyclic C ₂ - C ₂₀ alkylene, which can be substituted by OH, NH, NH ₂ , C(O) and/or aromatic alkynes, and

Ri is linear or branched, or cyclic C ₃ - C ₄₅ 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, NH ₂ , 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 C ₃ - C ₄₅ alkyl, which can be substituted by OH; linear or branched C ₃ - C ₄₅ 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 - C2oalkylene, 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 C ₃ - C ₄₅ alkyl, which can be substituted by OH; linear or branched C ₃ - C ₄₅ 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 C ₃ - C ₂₀ alkyl, which can be substituted by OH; linear or branched C ₃ - C ₂₀ 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) ) is hydrogenated.

Therefore, the present invention relates to a hydrogenation (H3””), which is hydro- genation (H3), wherein the compound of formula (lb) is hydrogenated. Therefore, the present invention relates to a hydrogenation (H3’””), which is hydro genation (H3), wherein the compound of formula (lc) ) is hydrogenated.

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), (H 1 ), (H2), (H3), (H3’), (H3”), (H3’”), (H3””) or (H3’””), wherein hydrogena tion is carried out in at least one solvent. Therefore, the present invention relates to a hydrogenation (H4’), which is hydrogena tion (H4), wherein at least one solvent is chosen from the group consisting of acetoni trile, ethanol and propanol.

Therefore, the present invention relates to a hydrogenation (H5), which is hydrogena tion (H), (H 1 ), (H2), (H3), (H3’), (H3”), (H3’”), (H3””) or (H3’””), wherein hydrogena tion is carried out without any solvent.

The hydrogenation according to the present invention is usually carried out at ele vated 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), (H1), (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). Pref erably 0.5 - 4 mol-%.

Therefore, the present invention relates to a hydrogenation (H9), which is hydrogena tion (H), (H1), (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), (H 1 ), (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), (H 1 ), (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 Co(OAc)24H ₂ 0 (0.12 g, 0.48 mmol), melamine (0.06 g, 0.48 mmol), EtOH (30 mL) and distilled water (1 mL) were stirred at RT for 15 mins. A pink solution with some suspended melamine formed. The flask was placed in an oil bath pre-heated to 60 °C and stirred for 1 h. S1O2 (Aerosil 0X50,

0.70 g) was added so that the Co was ca. 4 wt. % relative to S1O2. The suspension was stirred at RT overnight (22 h). Solvent was removed via rotary evaporation (45 °C, 80 mbar) to leave a pink powder which was dried overnight (19 h) at RT under high vacuum. The dry solid was ground to a fine powder and 0.262 g placed in a ce ramic 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, purg ing with argon the entire time. The oven was allowed to cool to room temperature, the crucible removed, and the catalyst (0.228 g, 87 % yield) transferred to a sample vial for storage.

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 following table (Table 1) shows the elemental analysis of the catalysts of the examples.

Table 1 : Elemental analysis of the prepared catalysts (pyrolysis temp 800 °C).

Hydrogenation Examples

Reduction of 3,7,11,15-tetramethylhexadec-1-yn-3-ol to isophytol using the catalyst 1 - 3 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 (72.4 mg, 0.25 mmol), cobalt catalyst (3.2 mg, 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 auto clave. The autoclave was sealed and flushed twice with H2 (20 bar) and then charged with H2 (30 bar). The autoclave was placed in an aluminium block pre-heated to 120 °C and maintained at this temperature for 15 h 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 centrif ugation (5000 RPM, 1 minute). 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: catalytic performance of the catalysts of table 1

Conditions: Substrate 0.25 mmol, Co catalyst (1 mol %), MeCN (2 mL), (120 °C, stir rate 750 RPM, 30 bar H ₂ , 15 h).

Table 3: The effect of solvent on the reactivity of the catalyst 1 of Table 1 .

Conditions: Co catalyst (1 mol %), Solvent (2 mL), (120 °C, stir rate 750 RPM, 30 bar H ₂ , 15 h).

Table 4: The effect of an 8 h reaction time on the catalytic performance of the cata lysts of table 1

Conditions: Co catalyst (1 mol %), MeCN (2 mL), (120 °C, stir rate 750 RPM, 30 bar H ₂ , 8 h). Table 5: The effect of a 20 bar H ₂ pressure on the catalytic performance of the cata lysts of table 1 rate 750 RPM, 20 bar H ₂ , 15 h).

Table 6: The effect of a 100 °C reaction temperature on the catalytic performance of the catalysts of table 1 rate 750 RPM, 30 bar H ₂ , 15 h).

After the reaction, the cobalt catalyst could be recovered from the reaction mixture via centrifugation and washed with ethyl acetate. After drying, the catalyst could then be used with similar activity (Table 7: ).

Table 7: Recycling demonstrated for the catalyst 1 of Table 1. Conditions: Substrate 0.25 mmol, Co catalyst (1 mol %), MeCN (2 mL), (120 °C, stir rate 750 RPM, 30 bar H ₂ , 15 h).

Reduction of MBY (2-methyl-3-butyn-2-ol) to MBE (2-methyl-3-buten-2-ol) using the catalyst 1 - 3 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), cobalt catalyst (3.2 mg, 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 (20 bar) and then charged with H2 (30 bar). The autoclave is placed in an aluminium block pre-heated to 120 °C and maintained at this temperature for 15 h 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 reac tion mixture diluted with chloroform (1 mL). The catalyst and reaction mixture are sep arated via centrifugation (5000 RPM, 1 minute). 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 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 - 3 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), cobalt catalyst (3.2 mg, 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 (20 bar) and then charged with H2 (30 bar). The autoclave is placed in an aluminium block pre-heated to 120 °C and maintained at this temperature for 15 h 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 stand ard and the reaction mixture diluted with chloroform (1 mL). The catalyst and reaction mixture are separated via centrifugation (5000 RPM, 1 minute). The recovered cata- lyst is washed with ethyl acetate (3 x 4 mL), separating via centrifugation as before, and then dried under high vacuum forca. 22 h. The reaction mixture is filtered through a celite plug and the product composition analysed via GC.

Linalool is obtained in good yields.