Comparison of the kinetics of bisphenol A synthesis on promoted and unpromoted ion exchanger catalysts

Jeřábek, Karel; Hun, Li Gwang; Setínek, K.

doi:10.1135/cccc19890321

Cited by 17 publications

(6 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A number of groups have disclosed the utility of using mixed thiol/sulfonic acid catalytic systems to enhance activity and selectivity. − However, Cheng and co-workers reported recently that catalysts containing incompletely oxidized sulfur species exhibited lower catalytic activity . From the data given in Table , the acid capacity of the propylsulfonic acid modified materials is always less than the sulfur elemental analyses, and this could indicate the presence of nonsulfonic acid sites on the surface.…”

Section: Resultsmentioning

confidence: 99%

Design of Heterogeneous Catalysts via Multiple Active Site Positioning in Organic−Inorganic Hybrid Materials

2003

View full text Add to dashboard Cite

Catalytic materials bearing multiple sulfonic acid functional groups and positioned at varying distances from one another on the surface of mesoporous solids are prepared to explore the effects that the spatial arrangement of active sites have on catalytic activity and selectivity. A series of organosiloxane precursors containing either disulfide or sulfonate ester functionalities (synthons of the eventual sulfonic acid groups) are synthesized. From these molecular precursors, a variety of organic-inorganic hybrid, mesostructured SBA-15 silica materials are prepared using a postsynthetic grafting procedure that leads to disulfide and sulfonate ester modified silicas:. By subsequent chemical derivatization of the grafted species, thiol and sulfonic acid modified silicas are obtained. The materials are characterized by a variety of spectroscopic ( 13 C and 29 Si CP MAS NMR, X-ray diffraction) and quantitative (TGA/DTA, elemental analysis, acid capacity titration) techniques. In all cases, the organic fragment of the precursor molecule is grafted onto the solid without measurable decomposition, and the precursors are, in general, attached to the surface of the mesoporous oxide by multiple siloxane bridges. The disulfide species 2‚SBA and 3‚SBA are reduced to the corresponding thiols 7‚SBA and 8‚SBA, respectively, and 4‚SBA and 6‚ SBA are transformed to the aryl sulfonic acids 11‚SBA and 12‚SBA, respectively. 7‚SBA and 8‚SBA differ only in terms of the level of control of the spatial arrangement of the thiol groups. Both 7‚SBA and 8‚SBA are further modified by oxidation with hydrogen peroxide to produce the alkyl sulfonic acid modified materials 9‚SBA and 10‚SBA, respectively. The performances of the sulfonic acid containing SBA-15 silica materials (with the exception of 12‚SBA) are tested as catalysts for the condensation reaction of phenol and acetone to bisphenol A. The alkyl sulfonic acid modified material 10‚SBA derived from the cleavage and oxidation of the dipropyl disulfide modified material 3‚SBA is more active than not only its monosite analogue 9‚ SBA, but also the presumably stronger acid aryl sulfonic acid material 11‚SBA. It appears that a cooperative effect between two proximal functional groups may be operating in this reaction.

show abstract

Section: Resultsmentioning

confidence: 99%

Design of Heterogeneous Catalysts via Multiple Active Site Positioning in Organic−Inorganic Hybrid Materials

2003

View full text Add to dashboard Cite

show abstract

“…The addition of thiols as a cocatalyst is known to improve both the rate of reaction and the selectivity to the desired isomer. 3,4 Mineral acids can be used to catalyze the bisphenol condensation reaction, but solid acid catalysts such as polymeric ionexchange resins are typically used for commercial bisphenol A production due to their recyclability. Thiols have been either added as a homogeneous feed additive 4 or bound to the resin surface by ion-pairing.…”

Section: Introductionmentioning

confidence: 99%

“…They are synthesized by the acid-catalyzed condensation between a ketone and phenol, yielding the desired p , p ′ isomer and a byproduct, the o,p ’ isomer (Scheme ). The addition of thiols as a cocatalyst is known to improve both the rate of reaction and the selectivity to the desired isomer. , …”

Section: Introductionmentioning

confidence: 99%

Nanoscale Organization of Thiol and Arylsulfonic Acid on Silica Leads to a Highly Active and Selective Bifunctional, Heterogeneous Catalyst

et al. 2008

View full text Add to dashboard Cite

Ordered mesoporous silicas functionalized with alkylsulfonic acid and thiol group pairs have been shown to catalyze the synthesis of bisphenols from the condensation of phenol and various ketones, with activity and selectivity highly dependent on the distance between the acid and thiol. Here, a new route to thiol/sulfonic acid paired catalysts is reported. A bis-silane precursor molecule containing both a disulfide and a sulfonate ester bond is grafted onto the surface of ordered mesoporous silica, SBA-15, followed by simultaneous disulfide reduction and sulfonate ester hydrolysis. The resulting catalyst, containing organized pairs of arylsulfonic acid and thiol groups, is significantly more active than the alkylsulfonic acid/thiol paired catalyst in the synthesis of bisphenol A and Z, and this increase in activity does not lead to a loss of regioselectivity. The paired catalyst has activity similar to that of a randomly bifunctionalized arylsulfonic acid/thiol catalyst in the bisphenol A reaction but exhibits greater activity and selectivity than the randomly bifunctionalized catalyst in the bisphenol Z reaction.

show abstract

“…Acid-catalyzed coupling reactions of LA with phenol proceed via protonation of the ketone which subsequently reacts with phenol to form DPA. − Of particular importance is the acid-thiol cooperative catalytic action of sulfonic acid-functionalized catalysts and thiol-containing compounds, first demonstrated for the condensation of acetone and phenol to BPA. − Recently, we reported that the combination of sulfonated hyperbranched poly(arylene oxindole)s (SHPAOs) and thiol promoters allows the catalytic synthesis of DPA in high yields (>50%) . The SHPAOs possess a high Brønsted acid density (4.3 mmol H + g –1 ), a high solubility in polar solvents and a low solution viscosity, which explains the growing interest for their use in catalytic applications. ,, To facilitate the reuse of the catalyst, we aimed to incorporate thiol promoters into the hyperbranched polymer matrix by neutralization of the sulfonic acid groups via ionic bonding with 2-aminoethanethiol or 2-(4-pyridyl)ethanethiol .…”

mentioning

confidence: 99%

Mechanistic Insights into the Kinetic and Regiochemical Control of the Thiol-Promoted Catalytic Synthesis of Diphenolic Acid

et al. 2012

View full text Add to dashboard Cite

The mechanism of the acid-catalyzed condensation between levulinic acid and phenol to form diphenolic acid (DPA) was investigated using a combination of sulfonated hyperbranched poly(arylene oxindole)s and thiols. Taft-type steric and electronic parameters were applied to study the correlation between the nature of the thiols and the condensation rate. The kinetic effect of thiols to tune the regiochemical control was shown to be dependent on the substituent size of the thiols. Although thiols cause an increase in the regioselectivity to the desired p,p'-DPA, the isomer distribution is found to converge to a thermodynamic equilibrium at high conversions of levulinic acid. The hitherto unconsidered acid-catalyzed isomerization of p,p'-DPA to o,p'-DPA was demonstrated by condensation reactions with both m-cresol and C-13-labeled phenol supported by density functional theory (DFT) calculations

show abstract

Comparison of the kinetics of bisphenol A synthesis on promoted and unpromoted ion exchanger catalysts

Cited by 17 publications

References 0 publications

Design of Heterogeneous Catalysts via Multiple Active Site Positioning in Organic−Inorganic Hybrid Materials

Design of Heterogeneous Catalysts via Multiple Active Site Positioning in Organic−Inorganic Hybrid Materials

Nanoscale Organization of Thiol and Arylsulfonic Acid on Silica Leads to a Highly Active and Selective Bifunctional, Heterogeneous Catalyst

Mechanistic Insights into the Kinetic and Regiochemical Control of the Thiol-Promoted Catalytic Synthesis of Diphenolic Acid

Contact Info

Product

Resources

About