22768-22-5

Upstream product

• 6362-80-7 2,4-diphenyl-4-methyl-pent-1-ene 
• 98-83-9 isopropenylbenzene 
• 617-94-7 1-methyl-1-phenylethyl alcohol 
• 2154-71-4 bis-trifluoromethyl-aminooxyl 
• 98-82-8 Isopropylbenzene 
• 80-15-9 Cumene hydroperoxide 
• 108-95-2 phenol 
• 2004-70-8 1-methylbuta-1,3-diene 
• 109-87-5 Dimethoxymethane 
• 75-54-7 Dichloromethylsilane 
• 100-42-5 styrene 

Downstream Products

• 31516-55-9 2,4-diphenyl-2-methylpentane 
• 98-83-9 isopropenylbenzene 
• 826-55-1 2-methyl-2-phenylpropionic acid 
• 5171-88-0 1,2-dicyclohexyl-1,1,2,2-tetramethylethane 
• 38970-72-8 2,4-dicyclohexyl-2-methyl pentane 

Relevant academic research and scientific papers

Oligomerization of α-methylstyrene in the presence of mordenite type zeolite

The activity and selectivity of coarse-porous H-mordenite in synthesis of cyclic and linear dimers of α-methylstyrene were studied.

Dimerization of α-methylstyrene in the presence of mordenite, aimed at preparation of transformer oils

Dimerization of α-methylstyrene in the presence of natural mordenite and its modified form was studied. The dependence of the yield and composition of the products on the process parameters was found. Conditions were determined for preparing linear dimers with a high selectivity.

Assembly of heteropoly acid nanoparticles in SBA-15 and its performance as an acid catalyst

Keggin-type 12-tungstophosphoric acid (TPA) nanocrystals have been assembled inside the pores of mesoporous silica through a vacuum impregnation method by using largepore SBA-15 as a nanoreactor. The product was characterized by Brunauer-Emmet-Teller particle size distri bution (BET-PSD), NMR and FT-IR spectroscopy, X-ray diffraction (XRD), tranmsission electron microscopy (TEM), differential thermal analysis (DTA) and FT-IR of adsorbed pyridine. The experimental results illustrale that the TPA nanocrystals are excellent Bronsted acid catalytic materials at room temperature.

Temperature-controlled highly selective dimerization of α-methylstyrene catalyzed by Br?nsted acidic ionic liquid under solvent-free conditions

A temperature-controlled highly selective dimerization of α-methylstyrene to produce 2,4-diphenyl-4-methyl-1-pentene and 1,1,3-trimethyl-3-phenylindan was catalyzed by Bro?nsted acidic ionic liquid [Hmim]+BF4-. At 60 °C, 2,4-diphenyl-4-methyl-1-pentene was formed in 93% selectivity with >92% conversion under a solvent-free condition while 1,1,3-trimethyl-3-phenylindan could be obtained in 100% selectivity when the reaction temperature was increased to 170 °C. The ionic liquid [Hmim]+BF4- could be reused with almost no loss of activity.

A kinetic model of the dimerization of α-methylstyrene in the presence of high-silica zeolite y

The kinetics of the dimerization of α-methylstyrene in the presence of high-silica zeolite HNaY has been studied, and a nine-stage scheme of the monomer conversion has been developed. Analysis of the kinetic models developed in the form of the Langmuir-Hinshelwood relationships and in terms of the mass action law has shown that the first model more adequately describes the experimental data. The numerical values of kinetic and adsorption parameters are represented. Pleiades Publishing, Ltd., 2012.

A liquid-liquid process for production of 2,4-diphenyl-4-methyl-1-pentene by dimerization of α-methylstyrene

A liquid-liquid process for the dimerization of α-methylstyrene (AMS) in order to produce selectively the commercially useful 2,4-diphenyl-4-methyl-l-pentene has been developed. The aqueous phase contained sulfuric acid as a catalyst and methanol as an additive, and the organic phase was 97% α-methylstyrene (AMS). An AMS conversion of 55% was achieved in 7 h when the dimerization was conducted at 80 °C. The product dimer contained 93% 2,4-diphenyl-4-methyl-1-pentene and only 0.06% 1,1,3-triniethyl-3-phenylindan, the saturated dimer. The liquid-liquid process can be used commercially to produce selectively 2,4-diphenyl-4-methyl-1-pentene at locations where cation-exchange resins are not readily available.

Dimerization of α-methylstyrene (AMS) catalyzed by sulfonic acid resins: A quantitative kinetic study

The dimerization of α-methylstyrene was examined at 50°C and 1 atm in nonpolar cumene and polar p-cresol solvents, using both soluble liquid acids and resin-based solid acids as catalysts. In particular, the activities of a representative macroporous sulfonic acid resin, Amberlyst-15, and Nafion perfluorosulfonic acid resin in three different microstructures, gel-type Nafion NR-50 resin, a carbon-supported Nafion resin, and a Nafion resin/silica composite material, have been compared. The Nafion resin/silica composites showed, by far, the highest activity. Supported Nafion resin on carbon and Amberlyst-15 are effective catalysts as well and are all more active than pure Nafion resin based on catalyst weight. None of the small molecule acids were sufficiently soluble to show significant catalytic action in the nonpolar solvent cumene. On the other hand, in the polar p-cresol media, the homogeneous acids showed relative activities in the same order as their pKas; and the strongest aqueous acid, triflic acid was more active than any of the resin catalysts on an acid equivalent basis. Among the resin catalysts, only the Nafion NR50 gel showed significant activity enhancement in p-cresol. In order to gain insight into these relative catalytic activities, the acid capacity and accessibility of acid groups in these solid acid catalysts were studied using temperature programmed desorption/thermogravimetric analysis (TPD/TGA) techniques with isopropanol as probe molecule. The TPD/TGA studies show that the sulfonic acid groups are readily accessible to 2-propanol vapor in the 13 wt% Nafion resin/SiO2 composite but not in gel-type Nafion resin and Amberlyst-15.

Reaction of bis(trifluoromethyl)amino-oxyl with t-butylbenzene, 2,2-diphenylpropane, benzylcyclopropane and some related alcohols

Reaction of the oxyl (CF3)2NO(.) (1) with t-butylbenzene (c. 3:1 molar ratio) at room temperature gives the hydroxylamine (CF3)2NOH (3) (43percent on oxyl) and a multicomponent higher-boiling mixture containing the substitution product (CF3)2NOCH2CMe2Ph (3) (28percent on arene), and the compounds 3-(CF3)2NC6H4CMe3 (5) (8percent on arene) and 4-(CF3)2NC6H4CMe3 (6) (6percent on arene).The reaction with 2,2-diphenylpropane (c. 4:1 molar ratio) at 70-80 deg C affords hydroxylamine 3 (45percent on oxyl) and a complex higher-boiling mixture, from which only the substitution product (CF3)2NOCH2CMePh2 (7) (36percent on arene) could be isolated.In contrast, the reaction of oxyl 1 with benzylcyclopropane at room temperature is clean and gives hydroxylamine 3 (49percent on oxyl) and the substitution product (8) (95percent on cyclopropane).From the reactions of oxyl 1 with 2-phenylpropan-2-ol (2:1 molar ratio), cyclopropylmethanol (c. 4:1 molar ratio) and 1-cyclopropylethanol (2:1 molar ratio) at room temperature, apart from hydroxylamine 3, the isolated products are a mixture of dimers of α-methylstyrene (10-12) (30percent on ol) and the 2:1 adduct of oxyl 1 and α-methylstyrene, i.e. (CF3)2NOCH2CMe(Ph)ON(CF3)2 (9) (50percent on ol); the ester (13) (99percent on ol); and the ketone (15) (60percent on ol), respectively.

Surface reactivity of non-hydrolytic silicophosphate xerogels: A simple method to create Br?nsted or Lewis acid sites on porous supports

Non-hydrolytic sol-gel reactions of silicon acetates with trimethylsilyl (TMS) esters of phosphoric and phosphonic acids produce cross-linked matrices containing homogeneous dispersions of silicate and phosphoryl groups connected together by networks of Si-O-P(=O) linkages. The condensation degrees reach 80 to 90%. Residual organic groups (10 to 20%) were reacted with a variety of compounds (H2O, Me3SiOSiMe3, POCl3, SiCl4, AlMe3, Al(NMe2)3, and AlCl3) in order to enrich the surface of these porous matrices with Br?nsted (≡P-OH) and Lewis (tetracoordinated Al) acid functional groups. The differences in the reactivity of ≡Si-OAc and ≡P-OSiMe3 groups were utilized for the selective modification at the silicon and phosphorus atoms. The reaction procedures were optimized and significantly porous silicophosphate materials with a high content of either hydroxyl groups or four-coordinated aluminium species were obtained. The activity and selectivity of prepared samples as catalysts for the dimerization of α-methylstyrene were tested. Excellent activities and moderate to very high selectivities were achieved suggesting the potential use of silicophosphate xerogels in heterogeneous catalysis.

Switching catalytic reaction conducted in pore void of mesoporous material by redox gate control

A molecular gate attached on the pore outlet of a mesoporous material, which is opened and closed by redox system of thiol groups, effectively switched the progress of a catalytic reaction promoted by the acidic site in the pore void. The Royal Society of Chemistry 2006.