53692-25-4

Upstream product

• 20657-25-4 bis(4-tert-butylphenyl)mercury(II) 
• 116840-52-9 cis-bis(4-tertbutylphenyl)bis(pyridine)platinum(II) 
• 253185-03-4 tert-butylbenzene 
• 92-52-4 biphenyl 
• 115-11-7 isobutene 
• 3972-65-4 1-bromo-4-tert-butylbenzene 
• 594-19-4 tert.-butyl lithium 
• 109-72-8 n-butyllithium 
• 507-20-0 tertiary butyl chloride 
• 769-92-6 4-tert-Butylaniline 

Downstream Products

• 1625-91-8 4,4'-di-tert-butylbiphenyl 
• 53692-24-3 3,3′-di-tert-butylbiphenyl 

Relevant academic research and scientific papers

METHOD FOR PRODUCING MULTISUBSTITUTED BIPHENYL COMPOUND AND SOLID CATALYST TO BE USED THEREIN

A method for producing a multisubstituted biphenyl compound is represented by the following formula (2), including a step of coupling a substituted benzene compound represented by the following formula (1) in the presence of a solid catalyst with gold immobilized onto a support.

Shape-selective alkylation of biphenyl over H-[Al]-SSZ-24 zeolites with AFI topology

H-[Al]-SSZ-24 zeolites with AFI topology were synthesized through the alumination of [B]-SSZ-24 zeolites, and applied for the alkylation of biphenyl (BP). H-[Al]-SSZ-24 zeolites have high activity for the isopropylation. The shape-selective formation of 4,4′-diisopropylbiphenyl (4,40-DIPB) occurred at moderate temperature; however, the selectivity for 4,40-DIPB decreased with an increase in the reaction temperature. Isomerization of 4,4′-DIPB occurred at higher temperatures over internal and external acid sites when there are enough acid sites inside the channels. The channels can discriminate 4,4′-DIPB from the other DIPB isomers in their transition states; however, they can not prevent the isomerization of 4,4′-DIPB at higher temperatures. The selectivity for the least bulky 4,4′-dialkylbiphenyl increased with the bulkiness of alkylating agents in the order: isopropylation s-butylation t-butylation. These results strongly support the shape-selective formation of the least bulky products inside the channels of H-[Al]-SSZ-24 zeolites.

The alkylation of biphenyl over one-dimensional twelve-membered ring zeolites. the influence of zeolite structure and alkylating agent on the selectivity for 4,4'-dialkylbiphenyl

Alkylation, i.e., isopropylation, s-butylation, and t-butylation, of biphenyl (BP) was examined over one-dimensional twelve-membered (12-MR) zeolites: Mordenite (MOR) and SSZ-24 (AFI) with straight channels, and SSZ-55 (ATS) and SSZ-42 (IFR) with corrugated channels. Types of zeolites and alkylating agents highly influenced the selectivities for dialkylbiphenyl (DABP) isomers. Shape-selective formation of 4,4'-diisopropylbiphenyl (4,4'-DIPB) was observed over MOR and AFI; however, ATS and IFR gave 4,4'-DIPB only in low selectivities at 250°C: 87% over MOR, 60% over AFI, 20% over ATS, and 30% over IFR. The selectivities for 4,4'-di-s-butylbiphenyl (4,4'-DSBB) in the,s-butyl-ation were higher than those for 4,4'-DIPB: 95% over MOR, 85% over AFI, 75% over ATS, and 50% over IFR. The t-butylation afforded selectively 4,4'-di-t-butylbiphenyl (4,4'-DTBB) over the zeolites: 96-97% over MOR and AFI, 90% over ATS, and 80% over IFR. These results in the alkylation indicate the exclusion of 4,4'-DABP from other bulky DABP isomers by steric restriction in zeolite channels is an important key for the high shape-selectivity. Even zeolites with large channels, such as ATS and IFR, can have shape-selective nature if the bulky moieties, such as,s-butyl and t- butyl groups, are large enough to differentiate the transition state of the least bulky 4,4'-DABP from those of the other isomers inside their channels. The selectivity for 4,4'-DABP decreased at high temperatures in some alkylations: isopropylation over MOR, and s-butylation and t-butylation over MOR, AFI, and ATS. The decreases are due to the iso-merization of 4,4'-DABP at external acid sites, because the channels are not large enough for the isomerization of 4,4'-DABP to bulkier 3,4'-DABP. However, the isopropylation over AFI was accompanied by the isomerization of 4,4'-DIPB at external and internal acid sites, because the channels are large enough for the isomerization of 4,4'-DIPB.

The alkylation of biphenyl over fourteen-membered ring zeolites. the influence of zeolite structure and alkylating agent on the selectivity for 4,4′-dialkylbiphenyl

Alkylation, i.e. isopropylation, s-butylation, and t-butylation, of biphenyl (BP) was examined over fourteen-mem-bered ring (14-MR) zeolites, CIT-5, UTD-1, and SSZ-53, in order to elucidate the relationships between structure of zeolites and bulkiness of alkylating agents on the shape-selective catalysis. CIT-5 zeolite (CFI) yielded 4,4′-diisopropyl- biphenyl (4,4′-DIPB) in the level of 50-60% in the isopropylation in the range of 150-300°C. 2,2′-, 2,3′-, and 2,4′-DIPB (2,x′-DIPB) isomers were obtained as the predominant DIPB isomers at lower temperatures, and the formation of 3,4′- and 3,3′-DIPB isomers increased with an increase in the temperature. However, the selectivities were in the level of 10- 15% for UTD-1 (DON) and SSZ-53 (SFH) zeolites in the range of 150-350°C. The s-butylation with 1-butene gave results similar to the isopropylation, although the selectivities for 4,4′-di-s-butylbiphenyl (4,4′-DSBB) were higher than those for 4,4′-DIPB at 250 °C: 80-85% for CFI, 40-50% for DON, and 30-40% for SFH. High selectivity for 4,4′-di-f-butylbiphenyl (4,4′-DTBB) was observed in the f-butylation at 250 °C: 95% for CFI, 90% for DON, and 80% for SFH. These differences are due to the spatial difference in their channels, and also due to bulkiness of alkylating agents, propene, 1-butene, and 2-methylpropene. The selectivity for 4,4′- dialkylbiphenyl (4,4′-DABP) was governed by the exclusion of the bulky DABP isomers at the transition state by steric restriction in the zeolite channels.

Effect of solvent on the lithium-bromine exchange of aryl bromides: Reactions of n-butyllithium and tert-butyllithium with 1-bromo-4-tert- butylbenzene at 0 °C

The outcome of reactions of 1-bromo-4-tert-butylbenzene (1), a representative aryl bromide, with n-BuLi or t-BuLi at 0 °C in a variety of solvent systems has been investigated. The products of reactions of 1 with n-BuLi vary significantly with changes in solvent composition: 1 does not react with n-BuLi in pure heptane; the exchange reaction to give (4-tert-butylphenyl) lithium, which is slow in pure diethyl ether, is virtually quantitative in heptane containing a small quantity of THF; and the reaction of 1 with n-BuLi in THF leads to considerable coupling. Lithium-bromine exchange is the virtually exclusive outcome of reactions of 1 with t-BuLi in every solvent studied except pure heptane: the presence of a small quantity of any of a variety of structurally diverse ethers (Et2O, THF, THP, MTBE) in the predominantly hydrocarbon medium affords (4-tert-butylphenyl)lithium, assayed as tert-butylbenzene, in yields exceeding 97%. The only side products observed from reactions of 1 with t-BuLi are small amounts of benzyne-derived hydrocarbons.

Mechanisms of thermal rearrangement of diarylbis(pyridine)platinum(II) complexes: Reductive carbon-carbon elimination versus hydrogen transfer

Thermolytic behavior in solution of a series of complexes cis-(py)2Pt(4-C6H4R)2 (R = H, CMe3, CF3; py = pyridine) has been examined. When R = CMe3, thermolytic rearrangement generates biaryl via unimolecular reductive elimination without prerequisite ligand dissociation. Arene elimination is an important, temperature-dependent, competitive reaction, which is suppressed by deuteriation of either aryl or pyridine ligands. Comparison with photolytic rearrangement of Hg(4-C6H4CMe3)2 indicates that Pt-C homolysis is not a significant contributor. A mechanism is indicated in which successive, reversible H transfers from pyridine and aryl ligands may occur, the latter resulting in a rare example of aryl group isomerization prior to elimination. For R = H, similar mechanistic competition is observed, but when R = CF3, concerted mononuclear reductive elimination is the only significant pathway. Its activation parameters suggest conformational restriction in the transition state. Metallic Hg alters the rearrangement pattern but not by scavenging heterogeneous byproducts.

tert-Butylation of Biphenyl; Determination of the Structure of Reaction Products by Means of Independent Syntheses

The Friedel-Crafts alkylation of biphenyl with tert-butyl chloride in carbon disulfide using aluminium trichloride as catalyst leads to the formation of only 9 of the 209 theoretically possible tert-butylbiphenyls, namely 3- and 4-tert-butylbiphenyl, 3,5-, 3,3'-, 3,4'-, and 4,4'-di-tert-butyl-biphenyl, 3,3',5-, and 3,4',5-tri-tert-butylbiphenyl as well as 3,3',5,5'-tetra-tert-butylbiphenyl.These have been separated by gas chromatography and identified by means of independently synthesized compounds in combination with GC-MS determinations.Five of these compounds have been prepared for the first time.