1
|
Goetjen TA, Knapp JG, Syed ZH, Hackler RA, Zhang X, Delferro M, Hupp JT, Farha OK. Ethylene polymerization with a crystallographically well-defined metal–organic framework supported catalyst. Catal Sci Technol 2022. [DOI: 10.1039/d1cy01990b] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Crystallographic characterization of a heterogeneous ethylene polymerization catalyst elucidates a chromium–carbon bond after alkyl aluminum activation and provides mechanistic insights.
Collapse
Affiliation(s)
- Timothy A. Goetjen
- Department of Chemistry and International Institute of Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, IL, USA 60208
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL, USA 60439
| | - Julia G. Knapp
- Department of Chemistry and International Institute of Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, IL, USA 60208
| | - Zoha H. Syed
- Department of Chemistry and International Institute of Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, IL, USA 60208
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL, USA 60439
| | - Ryan A. Hackler
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL, USA 60439
| | - Xuan Zhang
- Department of Chemistry and International Institute of Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, IL, USA 60208
| | - Massimiliano Delferro
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL, USA 60439
| | - Joseph T. Hupp
- Department of Chemistry and International Institute of Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, IL, USA 60208
| | - Omar K. Farha
- Department of Chemistry and International Institute of Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, IL, USA 60208
- Department of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL, USA 60208
| |
Collapse
|
2
|
Blitz JP, Diebel RE, Deakyne CA, Christensen JM, Gun'ko VM. Experimental and Computational Studies of Trialkylaluminum and Alkylaluminum Chloride Reactions with Silica. J Phys Chem B 2005; 109:5667-77. [PMID: 16851612 DOI: 10.1021/jp040483j] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Reactions of trimethylaluminum, triethylaluminum, and diethylaluminum chloride and ethylaluminum dichloride with silica gel have been studied experimentally by infrared spectroscopy and elemental analysis. The silica gel was subjected to different pretreatments to alter surface functionalities prior to reaction. In all cases the extent of surface modification reaction follows the trend unmodified > 600 degrees C pretreated > hexamethyldisilazane (HMDZ) pretreated > 600 degrees C/HMDZ pretreated. All of the aluminum compounds studied completely react non-hydrogen-bonded silanols, while also reacting with hydrogen-bonded silanols and siloxanes. Primarily monomeric surface species result from the surface modification reaction. Ethylaluminum chlorides preferentially react with silanols through cleavage of the Al-C bond rather than the Al-Cl bond. Singly bonded Si(s)-O-AlCl(2) surface species are readily synthesized by reaction of ethylaluminum dichloride with HMDZ-pretreated silica gel. Bridged bonded (Si(s)-O)(2)-AlCl surface species are readily synthesized by reaction of diethylaluminum chloride with HMDZ-pretreated silica gel. Computational ab initio studies of the cluster Si(4)O(6)(OH)(4) as a model to study the reaction of monomeric and dimeric methylaluminum dichloride with a silica silanol are also described. Comparison of the potential energy surface (PES) of monomer and dimer indicates that the energetics favor monomer reaction, consistent with experimental results. The energy cost in the dimer reaction is primarily from cleavage of a bridged Al-Cl bond upon adsorption. This does not occur when the monomer adsorbs. A comparison of the PES for the two reaction pathways resulting from cleavage of either an Al-Cl or Al-C bond indicates that while the former reaction is slightly kinetically favored (E(a) = 23.1 kJ/mol for Al-Cl bond cleavage versus E(a) = 31.1 kJ/mol for Al-C bond cleavage), the latter is strongly thermodynamically favored with an overall free energy difference between the two reaction pathways of 135 kJ/mol favorable to Al-C bond cleavage. These reactions are thermodynamically controlled.
Collapse
Affiliation(s)
- Jonathan P Blitz
- Department of Chemistry, Eastern Illinois University, Charleston, IL 61920, USA.
| | | | | | | | | |
Collapse
|
3
|
Kinetics and mechanistic insight into propylene polymerization with different metallocenes and various aluminium alkyls as cocatalysts. ACTA ACUST UNITED AC 1999. [DOI: 10.1016/s1381-1169(99)00055-2] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
4
|
Nagaoka SI, Koyano I, Imamura T, Masuoka T. Dissociative photoionization of Al2(Ch3)6 and Al2(Ch3)3Cl3 in the range 40-100 eV. Appl Organomet Chem 1991. [DOI: 10.1002/aoc.590050410] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
5
|
Heterogenization of homogeneous catalysts I. EPR study of (η-C5H5)2TiCl2/(C2H5)nAlCl3−n (n = 1, 2, 3) supported on silica gel. ACTA ACUST UNITED AC 1980. [DOI: 10.1016/0304-5102(80)80034-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
6
|
Smith J. Aluminium. J Organomet Chem 1978. [DOI: 10.1016/s0022-328x(00)84602-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
7
|
Reichert KH. Fortschritte auf dem Gebiet der Olefin-Polymerisation mit Ziegler-Katalysatoren. CHEM-ING-TECH 1977. [DOI: 10.1002/cite.330490805] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|