CpRu(CO)2(BF4) and [CpFe(CO)2(THF)]+ on mesoporous silica as adsorbents for the removal of dibenzothiophenes from hydrocarbon solutions

Abstract

The complexes, CpRu(CO)2(BF4) and [CpFe(CO)2(eta2-2-methylpropene)][BF4], react with dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-Me2DBT) to give [CpRu(CO)2(DBT)][BF4] and [CpFe(CO)2(4,6-Me2DBT)][BF4], whose structures were established by X-ray diffraction studies. The same types of products are obtained when dibenzothiophenes react with CpRu(CO)2(BF4) and [CpFe(CO)2(THF)][BF4] that are adsorbed on the mesoporous silica SBA-15. DRIFT and XPS studies indicate that CpRu(CO)2(BF4) and [CpRu(CO)2(DBT)][BF4] are adsorbed on the SBA-15 by hydrogen-bonding of the BF4- anions to surface Si-O-H groups. CpRu(CO)2(BF4)/SBA-15 removes 99% of the DBT in a 45% toluene/55% hexanes simulated petroleum feedstock. This solid phase extractant is less successful for sterically-hindered 4,6-Me2DBT, as only 72% of it is removed. The results show that CpRu(CO)2(BF4) can be immobilized by adsorption on mesoporous silica and that it reacts with dibenzothiophenes in the adsorbed form, CpRu(CO)2(BF4)/SBA-15, in much the same way that it reacts in solution.

A Mononuclear Cyclopentadiene–Iron Complex Grafted in the Supercages of HY Zeolite: Synthesis, Structure, and Reactivity

“…[18] It is worth noting that similar intrazeolite transformations have been proposed to yield half-sandwich organometallic fragments by the reactions of [(cot)Fe(CO) 3 ] (cot = cyclooctatriene) and [{CpFe(CO) 2 } 2 ] with acid zeolites. [19] These investigations suggested the need for a study to better understand the chemical nature of these so-called half-sandwich organometallic complexes inside a zeolite.…”

Synthetic, Structural, and Kinetic Studies of [CpRu(CO)2(μ2-η1(S):η6-DBT)RuCp*][PF6]2: A Dibenzothiophene Bridge between Two Ruthenium Fragments

“…This would reduce the rate of inversion at the sulfur, which would account for the fact that the two CO ligands in the {CpRu(CO) 2 } + unit remain inequivalent on the 13 C NMR time scale. The Ru−S distance in 4a (2.392(1) Å) is essentially the same as the corresponding distances in [CpRu(CO) 2 (η 1 ( S )-DBT)] + (2.398(2) Å) and [Cp*Ru(CO) 2 (η 1 ( S )-DBT)] + (2.394(1) Å) 6a. The tilt angle in 4a , which is the angle defined by Ru−S-Midpt (where Midpt is the midpoint between the C10 and C11 bond) is 114.5°, which is smaller than the values found for [CpRu(CO) 2 (η 1 ( S )-DBT)] + (119.3°), [Cp*Ru(CO) 2 (η 1 ( S )-DBT)] + (121.0°),20a and [CpFe(CO) 2 (η 1 ( S )-DBT)] + (119.4°) .…”

“…The Ru−S distance in 4a (2.392(1) Å) is essentially the same as the corresponding distances in [CpRu(CO) 2 (η 1 ( S )-DBT)] + (2.398(2) Å) and [Cp*Ru(CO) 2 (η 1 ( S )-DBT)] + (2.394(1) Å) 6a. The tilt angle in 4a , which is the angle defined by Ru−S-Midpt (where Midpt is the midpoint between the C10 and C11 bond) is 114.5°, which is smaller than the values found for [CpRu(CO) 2 (η 1 ( S )-DBT)] + (119.3°), [Cp*Ru(CO) 2 (η 1 ( S )-DBT)] + (121.0°),20a and [CpFe(CO) 2 (η 1 ( S )-DBT)] + (119.4°) . These angles are probably determined by crystal packing energies.…”

Development of a Flexible Strategy towards FR900482 and the Mitomycins

“…Ferrocene, which is used to construct such a catalytic intermediate, is a perfect precursor due to its two cyclopentadienyl groups. The intrazeolite chemistry, spectroscopy, and dynamics of metallocenes such as Cp 2 Fe, Cp 2 Cr, and Cp 2 Co, and intrazeolite half‐sandwich carbonyl compounds of iridium and rhodium, have been studied in detail,17 and [CpFe(CO) 2 (thf)] + anchored to mesoporous silica has been used as an adsorbent for the removal of dibenzothiophenes 18. It is worth noting that similar intrazeolite transformations have been proposed to yield half‐sandwich organometallic fragments by the reactions of [(cot)Fe(CO) 3 ] (cot=cyclooctatriene) and [{CpFe(CO) 2 } 2 ] with acid zeolites 19.…”