Catalyst composition and process for oligomerization of ethylene
A catalyst composition including: (a) a chromium compound; (b) a ligand of the general structure R 1 R 2 P—N(R 3 )—P(R 4 )—NR 5 R 6 or (A) R 1 R 2 P—N(R 3 )—P(XR 7 )R 8 or R 1 R 2 P—N(R 3 )—P(XR 7 ) 2 , with X═O or S, (B) wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 and R 8 are independently C 1 -C 10 -alkyl, C 6 -C 20 -aryl, C 3 -C 10 -cycloalkyl, aralkyl, alkylaryl, or trialkylsilyl, or any cyclic derivatives of (A) and (B), wherein at least one of the P or N atoms of the PNPN-unit or PNP-unit is a member of the ring system, the ring system being formed from one or more constituent compounds of structures (A) or (B) by substitution; and (c) an activator or co-catalyst; and a process for tri- and/or tetramerization.
1. A catalyst composition comprising:
(a) a chromium compound;
(b) a ligand of the general structure
(B) R 1 R 2 P—N(R 3 )—P(XR 7 )R 8 , with X═O or S, wherein R 1 , R 2 , R 3 , and R 8 are independently C 1 -C 10 -alkyl, C 6 -C 20 -aryl, C 3 -C 10 -cycloalkyl, arylalkyl, alkylaryl, or trialkylsilyl, or any cyclic derivatives of (B), wherein at least one of the P or N atoms of the PNP-unit is a member of the ring system, the ring system being formed from one or more constituent compounds of structure (B) by substitution, and wherein R 7 is C 1 -C 10 -alkyl, C 3 -C 10 -cycloalkyl, arylalkyl, or trialkylsilyl; and
(c) an activator or co-catalyst.
2. The catalyst composition according to claim 1 , wherein the chromium compound is an organic salt, an inorganic salt, a coordination complex, an organometallic complex of Cr(0) or Cr(III), or a combination comprising at least one of the foregoing.
3. The catalyst composition according to claim 2 , wherein the chromium compound is CrCl 3 (THF) 3 , Cr(III)acetylacetonate, Cr(III)octanoate, chromium hexacarbonyl, Cr(III)-2-ethylhexanoate, (benzene)tricarbonyl-chromium, or a combination comprising at least one of the foregoing.
4. The catalyst composition according to claim 1 , wherein R 1 , R 2 , R 3 , R 7 , and R 8 are each independently methyl, ethyl, isopropyl, tert-butyl, cyclohexyl, phenyl, benzyl, tolyl, or xylyl.
5. The catalyst composition according to claim 1 , wherein the activator or co-catalyst is trimethylaluminum, triethylaluminum, triisopropylaluminum, triisobutylaluminum, ethylaluminumsesquichloride, diethylaluminum chloride, ethylaluminumdichloride, methylaluminoxane (MAO), modified methylaluminoxane (MMAO), or a combination comprising at least one of the foregoing.
6. The catalyst composition according to claim 5 , wherein the Al/Cr molar ratio is from 1:1 to 1000:1.
7. The catalyst composition according to claim 1 , wherein the ligand is Ph 2 P—N(i-Pr)—P(Ph)S(i-Pr), Ph 2 P—N(i-Pr)—P(Ph)OC 2 H 5 , Ph 2 P—N(i-Pr)P(Ph)OCH 3 , or a combination comprising at least one of the foregoing.
8. The catalyst composition according to claim 1 , additionally comprising a solvent, wherein the solvent is one of aromatic hydrocarbons, straight-chain aliphatic hydrocarbons, cyclic aliphatic hydrocarbons, straight-chain olefins, ethers, or a combination comprising at least one of the foregoing.
9. The catalyst composition according to claim 8 , wherein the concentration of the chromium compound is from 0.01 to 100 mmol/l.
10. The catalyst composition according to claim 1 , wherein the ligand/Cr molar ratio is from 0.5 to 50.
11. The catalyst composition of claim 1 , wherein R 7 is C 1 -C 10 -alkyl, C 3 -C 10 -cycloalkyl, unsubstituted arylalkyl, or trialkylsilyl.
12. A catalyst composition, obtainable by combining at least:
(a) a chromium compound;
(b) a ligand of the general structure
(B) R 1 R 2 P—N(R 3 )—P(XR 7 )R 8 ,
wherein
X═O or S, and
R 1 , R 2 , R 3 , and R 8 are independently C 1 -C 10 -alkyl, C 6 -C 20 -aryl, C 3 -C 10 -cycloalkyl, arylalkyl, alkylaryl, or trialkylsilyl, or any cyclic derivatives of (B), wherein at least one of the P or N atoms of the PNP-unit is a member of the ring system, the ring system being formed from one or more constituent compounds of structure (B) by substitution, and wherein R 7 is C 1 -C 10 -alkyl, C 3 -C 10 -cycloalkyl, arylalkyl, or trialkylsilyl; and
(c) an activator or co-catalyst.
13. A catalyst composition comprising:
(a) a chromium compound;
(b) a ligand of the general structure
(B) R 1 R 2 P—N(R 3 )—P(XR 7 )R 8 , with X═O or S, wherein R 1 , R 2 , R 3 , and R 8 are independently C 1 -C 10 -alkyl, unsubstituted C 6 -C 20 -aryl, C 3 -C 10 -cycloalkyl, arylalkyl, alkylaryl, or trialkylsilyl, or any cyclic derivatives of (B), wherein at least one of the P or N atoms of the PNP-unit is a member of the ring system, the ring system being formed from one or more constituent compounds of structure (B) by substitution and wherein R 7 is C 1 -C 10 -alkyl, C 3 -C 10 -cycloalkyl, unsubstituted arylalkyl, or trialkylsilyl; and
(c) an activator or co-catalyst.