61434-46-6

Basic information

• Product Name: 3,4'-DI-ISO-PROPYLBIPHENYL
• Synonyms: 1,1'-Biphenyl, 3,4'-bis-(1-methylethyl);1,1'-Biphenyl, 3,4'-diisopropyl;3,4'-Diisopropyl-1,1'-biphenyl;3,4'-DI-ISO-PROPYLBIPHENYL;TIMTEC-BB SBB007851
• CAS NO: 61434-46-6
• Molecular Formula: C₁₈H₂₂
• Molecular Weight: 238.37
• Mol File: 61434-46-6.mol

Chemical Properties

• Boiling Point: 336.1±22.0 °C(Predicted)
• Appearance: /
• Density: 0.935±0.06 g/cm3(Predicted)
• CAS DataBase Reference: 3,4'-DI-ISO-PROPYLBIPHENYL(CAS DataBase Reference)
• NIST Chemistry Reference: 3,4'-DI-ISO-PROPYLBIPHENYL(61434-46-6)
• EPA Substance Registry System: 3,4'-DI-ISO-PROPYLBIPHENYL(61434-46-6)

Safety Data

• Hazardous Substances Data: 61434-46-6(Hazardous Substances Data)

Usage

Uses

Used in Heat Transfer Fluids Industry:
3,4'-DI-ISO-PROPYLBIPHENYL is used as a heat transfer fluid for its outstanding thermal stability and low volatility, which are crucial for maintaining efficient heat transfer in various industrial processes.
Used in Electronics Industry:
In the electronics industry, 3,4'-DI-ISO-PROPYLBIPHENYL serves as a dielectric coolant for transformers and capacitors, leveraging its thermal and chemical properties to ensure the efficient operation and longevity of these components.
Used in Industrial Processes:
3,4'-DI-ISO-PROPYLBIPHENYL is also utilized in a range of industrial processes where its heat transfer capabilities and chemical stability are advantageous for high-temperature applications.

Upstream product

• 92-52-4 biphenyl 
• 187737-37-7 propene 

Downstream Products

• 18970-30-4 4,4' diisopropylbiphenyl 
• 69375-12-8 3,3'-di-isopropylbiphenyl 

Relevant articles and documents

The isopropylation of biphenyl over transition metal substituted aluminophosphates: MAPO-5 (M: Co and Ni)

The isopropylation of biphenyl (BP) was examined over transition metal substituted aluminophosphates (MAPO-5; M: Co and Ni) with 12-membered (12-MR) oxygen ring pore-entrances of AFI topology. The MAPO-5 samples were synthesized by dry gel conversion method using trimethylamine as a structure directing agent, and their properties were characterized by XRD, XPS, SEM, N2 adsorption, NH3-TPD, pyridine adsorption, and o-xylene uptake. They are clear crystals without impurity phases and agglomerates, and found small amounts of Br?nsted acid sites which are expecting active for acid catalysis. The isopropylation of BP over both of Co(5)APO-5 and Ni(5)APO-5 at 250 °C gave the high selectivities for 4,4′-DIPB: 65-75%. 4-IPBP is almost exclusive precursor of 4,4′- and 3,4′-DIPB. 3-IPBP was not significantly concerned even though 3-IPBP was predominant among IPBP isomers at the late stages: the MAPO-5 channels allow preferential access of 4-IPBP, and prevent the access of 3-IPBP due to reactant selectivity mechanism. The selective formation of 4,4′-DIPB occurred by preferential exclusion of bulkier 3,4′-DIPB and other isomers through the steric interaction of transition states with the channels by the restricted transition state selectivity mechanism. MAPO-5 (M: Co and Ni) has the same level of the selectivities for 4,4′-DIPB to SSZ-24 and other MAPO-5 (M: Si, Mg, and Zn), and these selectivities were originated by the AFI channels. The selectivities for 4,4′-DIPB were kept 65-75% at low and moderate temperatures over MAPO-5 (M: Co and Ni); however, they were decreased by the isomerization to stable 3,4′-DIPB with the increase in temperature.

Shape-selective alkylation of biphenyl with propylene using zeolite and amorphous silica-alumina catalysts

The influence of zeolite structure for the alkylation of biphenyl with propylene was studied over various zeolites such as HY, HZSM-5, and dealuminated mordenite (DMOR), as well as amorphous SiO2/Al2O 3, in a stirred tank reactor. Biphenyl conversion was found to increase with reaction time for HZSM-5 and DMOR zeolites and reach a leveling off in 4 h, whereas for HY and amorphous SiO2/Al2O 3 a leveling off was reached within an hour. DMOR displayed the highest selectivity for 4,4′-diisopropylbiphenyl (4,4′-DIPB) even at temperatures as high as 300 °C, whereas for HY, HZSM-5 and amorphous SiO2/Al2O3 selectivities fell in the range of 10-35%; they were significantly lower than observed for DMOR. These differences in selectivity might be due to the structure and pore channels of the zeolites. DMOR was found to be an active catalyst, the selectivity for 4-isopropylbiphenyl (4-IPB) and (4,4′-DIPB) was high among isopropylbiphenyl (IPB) and diisopropylbiphenyl (DIPB) isomers, respectively, indicating DMOR possesses shape-selectivity. The selectivity of 4,4′-DIPB increased with time, while the corresponding selectivity of 4-IPB decreased for DMOR catalyst. Alkylation of biphenyl with propylene occurred with predominant formation of 4-IPB in the first step. 4-IPB is only a source in the second step of alkylation of biphenyl with propylene for the formation of 4,4′-DIPB, while 3-IPB does not participate in the formation of DIPB isomers.

Isopropylation of biphenyl over ZSM-12 zeolites

ZSM-12 zeolites, ZSM-12L and ZSM-12S, with MTW topology were synthesized by using methyltriethylammonium bromide (MTEABr) and tetraethylammnoium bromide (TEABr) as structure directing agents (SDA), respectively, for the isopropylation of biphenyl (BP) usi

Preparation of [Fe]-SSZ-24 through the isomorphous substitution of [B]-SSZ-24 with iron, and its catalytic properties in the isopropylation of biphenyl

[Fe]-SSZ-24, a ferrosilicate with AFI topology, was prepared through an isomorphous substitution of [B]-SSZ-24 with iron, and applied for the isopropylation of biphenyl (BP) to understand the mechanism of shape-selective catalysis. The substitution of [B]-SSZ-24 with an aqueous solution of a limited amount of Fe(NO3)3·6H2O effectively gave [Fe]-SSZ-24, and its XRD gave clear patterns of AFI topology without the peaks assigned to Fe2O3. [Fe]-SSZ-24 exhibited enhanced catalytic activity for the isopropylation of BP. Shape-selective formation of 4,4′-diisopropylbiphenyl (4,4′-DIPB) occurred at moderate temperatures (250-300 °C); however, the decreases of the selectivity for 4,4′-DIPB occurred at high temperatures (325-350 °C). On the other hand, the selectivities for 4,4′-DIPB in encapsulated products remained almost constant (ca 75%), irrespective of the reaction temperature and the SiO2/Fe2O3 ratios. The differences in the selectivities for 4,4′-DIPB between bulk and encapsulated products indicate that shape-selective formation of 4,4′-DIPB occurs in the [Fe]-SSZ-24 channels, and these channels prevent the isomerization of 4,4′-DIPB, even at 350 °C. These results suggest that the channels of SSZ-24 can discriminate 4,4′-DIPB from other possible DIPB isomers at their transition states although high reaction temperatures cause isomerization at external acid sites. Large pore molecular sieves of AFI topology, [Fe]-SSZ-24, [Al]-SSZ-24, MgAPO-5, ZnAPO-5, and SAPO-5, gave similar levels of selectivities for 4,4′-DIPB in the isopropylation of BP. These results indicate that the framework of AFI topology primarily controls shape-selective formation of 4,4′-DIPB, although catalytic activities of the materials were dependent on acidic properties.

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.

Continuous Process for preparing 4,4'-diisopropylbiphenyl

A continuous flow process has been discovered for the highly selective isopropylation of biphenyl to 4,4'-diisopropylbiphenyl. Thus biphenyl and propene in decalin are passed through a solid catalyst bed contained in a flow reactor at moderate temperature (220°C) and pressure (10-30 atm) together with a continuous stream of nitrogen. The catalyst is an acidic zeolite catalyst having a molar ratio of SiO2 to Al2O3 in a range between about 20 to 1 and about 500 to 1. Optimal catalytic performance is achieved when 35% or more of the active sites in the catalyst have an activation energy of ammonia desorption in a range between about 145 kJ/mol and about 170 kJ/mol. Additional enhancements of catalyst performance can be achieved by pretreating the acidic zeolite catalyst with a volatile basic agent prior to the alkylation reaction.

Deactivation of External Acid Sites of H-Mordenite with Ceria Modification in the Isopropylation of Biphenyl

Cerium modification of H-mordenite was highly effective for the deactivation of acid sites on external surfaces in the isopropylation of biphenyl. The selectivity for 4,4'-diisopropylbiphenyl (4,4'-DIPB) over unmodified H-mordenite decreased with the increase of reaction temperature because of the isomerization of 4,4'-DIPB at the external acid sites. The isomerization was effectively prevented by the ceria modification of H-mordenites.