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METHOD FOR PRODUCING ARENE COMPOUNDS AND ARENE COMPOUNDS PRODUCED BY THE SAME
Provided is a method for producing (alkyl)arene compounds represented by Formulae 3-1, 3-2, and 3-3 by the Friedel-Crafts alkylation reaction of alkyl halide compounds and arene compounds using organic phosphine compounds as a catalyst.
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(2021/06/26)

Cobalt?NHC Catalyzed C(sp2)?C(sp3) and C(sp2)?C(sp2) Kumada Cross-Coupling of Aryl Tosylates with Alkyl and Aryl Grignard Reagents
The first cobalt-catalyzed cross-coupling of aryl tosylates with alkyl and aryl Grignard reagents is reported. The catalytic system uses CoF3 and NHCs (NHC=N-heterocyclic carbene) as ancillary ligands. The reaction proceeds via highly selective C?O bond functionalization, leading to the corresponding products in up to 98 % yield. The employment of alkyl Grignard reagents allows to achieve a rare C(sp2)?C(sp3) cross-coupling of C?O electrophiles, circumventing isomerization and β-hydride elimination problems. The use of aryl Grignards leads to the formation of biaryls. The C?O cross-coupling sets the stage for a sequential cross-coupling by exploiting the orthogonal selectivity of the catalytic system.
Piontek, Aleksandra,Och?dzan-Siod?ak, Wioletta,Bisz, Elwira,Szostak, Michal
p. 202 - 206
(2020/12/01)

Efficient Pd-Catalyzed Direct Coupling of Aryl Chlorides with Alkyllithium Reagents
Organolithium compounds are amongst the most important organometallic reagents and frequently used in difficult metallation reactions. However, their direct use in the formation of C?C bonds is less established. Although remarkable advances in the coupling of aryllithium compounds have been achieved, Csp2?Csp3 coupling reactions are very limited. Herein, we report the first general protocol for the coupling or aryl chlorides with alkyllithium reagents. Palladium catalysts based on ylide-substituted phosphines (YPhos) were found to be excellently suited for this transformation giving high selectivities at room temperature with a variety of aryl chlorides without the need for an additional transmetallation reagent. This is demonstrated in gram-scale synthesis including building blocks for materials chemistry and pharmaceutical industry. Furthermore, the direct coupling of aryllithiums as well as Grignard reagents with aryl chlorides was also easily accomplished at room temperature.
Dilchert, Katharina,Gessner, Viktoria H.,Gro?johann, Angela,Rodstein, Ilja,Scherpf, Thorsten,Steinert, Henning,Tappen, Jens
supporting information
p. 20596 - 20603
(2020/09/09)

C-F activation for C(sp2)-C(sp3) cross-coupling by a secondary phosphine oxide (SPO)-nickel complex
A secondary phosphine oxide (SPO)-nickel catalyst allowed the activation of otherwise inert C-F bonds of unactivated arenes in terms of challenging couplings with primary and secondary alkyl Grignard reagents. The C-F activation is characterized by mild reaction conditions and high levels of branched selectivity. Electron-rich and electron-deficient arenes were suitable electrophiles for this transformation. In addition, this strategy also proved suitable to heterocycles and for the activation of C-O bonds under slightly modified conditions.
Müller, Valentin,Ghorai, Debasish,Capdevila, Lorena,Messinis, Antonis M.,Ribas, Xavi,Ackermann, Lutz
supporting information
p. 7034 - 7040
(2020/09/15)

Nickel-Catalyzed C(sp2)?C(sp3) Kumada Cross-Coupling of Aryl Tosylates with Alkyl Grignard Reagents
Aryl tosylates are an attractive class of electrophiles for cross-coupling reactions due to ease of synthesis, low price, and the employment of C?O electrophiles, however, the reactivity of aryl tosylates is low. Herein, we report the Ni-catalyzed C(sp2)?C(sp3) Kumada cross-coupling of aryl tosylates with primary and secondary alkyl Grignard reagents. The method delivers valuable alkyl arenes by cross-coupling with challenging alkyl organometallics possessing β-hydrogens that are prone to β-hydride elimination and homo-coupling. The reaction is catalyzed by an air- and moisture stable-Ni(II) precatalyst. A broad range of electronically-varied aryl tosylates, including bis-tosylates, underwent this transformation, and many examples are suitable at mild room temperature conditions. The combination of Ar?X cross-coupling with the facile Ar?OH activation/cross-coupling strategy permits for orthogonal cross-coupling with challenging alkyl organometallics. Furthermore, we demonstrate that the method operates with TON reaching 2000, which is one of the highest turnovers observed to date in Ni-catalyzed cross-couplings. (Figure presented.).
Piontek, Aleksandra,Och?dzan-Siod?ak, Wioletta,Bisz, Elwira,Szostak, Michal
supporting information
p. 2329 - 2336
(2019/04/13)

Bioinspired Metal-Free Formal Decarbonylation of α-Branched Aliphatic Aldehydes at Ambient Temperature
A sequence of a Baeyer–Villiger oxidation and a Lewis acid-promoted reduction of the resulting formate with Et3SiH enabled the metal-free formal decarbonylation of tertiary and secondary aliphatic aldehydes. The new methodology mimics the biosynthetic decarbonylation pathway through oxidative C?C bond cleavage rather than the C(O)?H bond activation known from conventional Tsuji–Wilkinson-type reactions. The substrate scope is complementary to existing transition-metal-catalyzed protocols.
Richter, Sven C.,Oestreich, Martin
supporting information
p. 8508 - 8512
(2019/06/04)

Murahashi Cross-Coupling at ?78 °C: A One-Pot Procedure for Sequential C?C/C?C, C?C/C?N, and C?C/C?S Cross-Coupling of Bromo-Chloro-Arenes
The coupling of organolithium reagents, including strongly hindered examples, at cryogenic temperatures (as low as ?78 °C) has been achieved with high-reactivity Pd-NHC catalysts. A temperature-dependent chemoselectivity trigger has been developed for the selective coupling of aryl bromides in the presence of chlorides. Building on this, a one-pot, sequential coupling strategy is presented for the rapid construction of advanced building blocks. Importantly, one-shot addition of alkyllithium compounds to Pd cross-coupling reactions has been achieved, eliminating the need for slow addition by syringe pump.
Sinha, Narayan,Heijnen, Dorus,Feringa, Ben L.,Organ, Michael G.
supporting information
p. 9180 - 9184
(2019/07/04)

Water and Sodium Chloride: Essential Ingredients for Robust and Fast Pd-Catalysed Cross-Coupling Reactions between Organolithium Reagents and (Hetero)aryl Halides
Direct palladium-catalysed cross-couplings between organolithium reagents and (hetero)aryl halides (Br, Cl) proceed fast, cleanly and selectively at room temperature in air, with water as the only reaction medium and in the presence of NaCl as a cheap additive. Under optimised reaction conditions, a water-accelerated catalysis is responsible for furnishing C(sp3)–C(sp2), C(sp2)–C(sp2), and C(sp)–C(sp2) cross-coupled products, in competition with protonolysis, within a reaction time of 20 s, in yields of up to 99 %, and in the absence of undesired dehalogenated/homocoupling side products even when challenging secondary organolithiums serve as the starting material. It is worth noting that the proposed protocol is scalable and the catalyst and water can easily and successfully be recycled up to 10 times, with an E-factor as low as 7.35.
Dilauro, Giuseppe,Quivelli, Andrea Francesca,Vitale, Paola,Capriati, Vito,Perna, Filippo Maria
supporting information
p. 1799 - 1802
(2019/01/25)

Discovery of flexible naphthyltriazolylmethane-based thioacetic acids as highly active uric acid transporter 1 (URAT1) inhibitors for the treatment of hyperuricemia of gout
Background: Gout is the most common inflammatory arthritis, which, if left untreated or inadequately treated, will lead to joint destruction, bone erosion and disability due to the crystal deposition. Uric acid transporter 1 (URAT1) was the promising therapeutic target for urate-lowering therapy. Objective: The goal of this work is to understand the structure-activity relationship (SAR) of a potent lesinurad-based hit, sodium 2-((5-bromo-4-((4-cyclopropyl-naphth-1-yl)methyl)-4H-1,2,4-triazol-3-yl)thio)acetate (1c), and based on that discover a more potent URAT1 inhibitor. Methods: The SAR of 1c was systematically explored and the in vitro URAT1 inhibitory activity of synthesized compounds 1a-1t was determined by the inhibition of URAT1-mediated [8-14C]uric acid uptake by human embryonic kidney 293 (HEK293) cells stably expressing human URAT1. Results: Twenty compounds 1a-1t were synthesized. SAR analysis was performed. Two highly active URAT1 inhibitors, sodium 2-((5-bromo-4-((4-n-propylnaphth-1-yl)methyl)-4H-1,2,4-triazol-3-yl)thio)acetate (1j) and sodium 2-((5-bromo-4-((4-bromonaphth-1-yl)methyl)-4H-1,2,4-triazol-3-yl)thio)acetate (1m), were identified, which were 78- and 76-fold more active than parent lesinurad in in vitro URAT1 inhibitory assay, respectively (IC50 values for 1j and 1m were 0.092 μM and 0.094 μM, respectively, against human URAT1 vs 7.18 μM for lesinurad). Conclusion: Two highly active URAT1 inhibitors were discovered. The SAR exploration also identified more flexible naphthyltriazolylmethane as a novel molecular skeleton that will be valuable for the design of URAT1 inhibitors, as indicated by the observation that many of the synthesized naphthyltriazolylmethane-bearing derivatives (1b-1d, 1g, 1j and 1m) showed significantly improved UART1 inhibitory activity (sub-micromolar IC50 values) as compared with lesinurad which has the rigid naphthyltriazole skeleton.
Zhang, Xiansheng,Wu, Jingwei,Liu, Wei,Liu, Yuqiang,Xie, Yafei,Shang, Qian,Zhou, Zhixing,Xu, Weiren,Tang, Lida,Wang, Jianwu,Zhao, Guilong
p. 260 - 281
(2017/05/31)

Iron-Catalyzed C(sp2)–C(sp3) Cross-Coupling of Alkyl Grignard Reagents with Polyaromatic Tosylates
The iron-catalyzed cross-coupling of polyaromatic tosylates with alkyl Grignard reagents controlled by O-coordinating ligand is reported. The reaction operates under very mild, operationally practical conditions to furnish alkylated polyaromatics that are a common motif in a wide range of electronic-material, pharmaceutical and high-performance fluid applications. The challenging C(sp2)–C(sp3) cross-coupling products are obtained in good to excellent yields obviating the problems associated with β-hydride elimination. For the first time the coupling of polyaromatic tosylates can be achieved in the presence of sensitive carboxylic acid derived functional groups. Mechanistic studies suggest that the reaction selectivity can be correlated with the reduction potential of polyaromatic hydrocarbons. The method represents a rare example of sustainable C–O bond alkylation of polyarenes at room temperature.
Piontek, Aleksandra,Szostak, Michal
p. 7271 - 7276
(2018/01/02)

Efficient cross-coupling of aryl/alkenyl triflates with acyclic secondary alkylboronic acids
Aryl-secondary alkyl cross-coupling with aryl sulfonate esters as coupling partners remains a significant challenge. Efficient cross-coupling between aryl/alkenyl triflates and acyclic secondary alkylboronic acids is realized for the first time to provide a series of sterically congested acyclic secondary alkyl arenes/olefins in good to excellent yields. The employment of sterically bulky P,PO ligand L1/L2 is crucial for the high yields and selectivities. The method has enabled a concise and 4-step synthesis of a key intermediate of male contraceptive agent and PAF antagonist gossypol.
Si, Tengda,Li, Bowen,Xiong, Wenrui,Xu, Bin,Tang, Wenjun
supporting information
p. 9903 - 9909
(2017/12/12)

Nickel-Catalyzed Cross-Coupling of Organolithium Reagents with (Hetero)Aryl Electrophiles
Nickel-catalyzed selective cross-coupling of aromatic electrophiles (bromides, chlorides, fluorides and methyl ethers) with organolithium reagents is presented. The use of a commercially available nickel N-heterocyclic carbene (NHC) complex allows the reaction with a variety of (hetero)aryllithium compounds, including those prepared via metal-halogen exchange or direct metallation, whereas a commercially available electron-rich nickel-bisphosphine complex smoothly converts alkyllithium species into the corresponding coupled product. These reactions proceed rapidly (1 h) under mild conditions (room temperature) while avoiding the undesired formation of reduced or homocoupled products. Nickel-catalyzed cross-coupling of aromatic electrophiles with organolithium reagents is presented. The use of a commercially available nickel N-heterocyclic carbene complex allows reaction with a variety of (hetero)aryllithium compounds, whereas a commercially available electron-rich nickel bisphosphine complex smoothly converts alkyllithium species into the corresponding coupled product.
Heijnen, Dorus,Gualtierotti, Jean-Baptiste,Hornillos, Valentín,Feringa, Ben L.
supporting information
p. 3991 - 3995
(2016/03/16)

Efficient synthesis of sterically hindered arenes bearing acyclic secondary alkyl groups by suzuki-miyaura cross-couplings
Bulky P,P-O ligands were designed to inhibit isomerization and reduction side reactions during the cross coupling between sterically hindered aryl halides and alkylboronic acids. Suzuki-Miyaura cross-couplings between di-ortho-substituted aryl bromides and acyclic secondary alkylboronic acids have been achieved with high yields. The method has also enabled the preparation of ortho-alkoxy di-ortho-substituted arenes bearing isopropyl groups in excellent yields. The utility of the synthetic method has been demonstrated in a late-stage modification of estrone and in the application to a new synthetic route toward gossypol. No side reaction: The shown bulky P,P-O ligands (right) successfully inhibit isomerization and reduction side reactions of the cross-coupling of sterically hindered substrates such as di-ortho-substituted aryl bromides with acyclic secondary alkylboronic acids. The method also allows the preparation of ortho-alkoxy di-ortho-substituted isopropyl arenes in excellent yields.
Li, Chengxi,Chen, Tianyu,Li, Bowen,Xiao, Guolan,Tang, Wenjun
supporting information
p. 3792 - 3796
(2015/03/18)

Aryl/heteroaryl pentafluorobenzenesulfonates (ArOPFBs): New electrophilic coupling partners for room temperature Suzuki-Miyaura cross-coupling reactions
The first cross-coupling reaction between aryl/heteroaryl pentafluorobenzenesulfonates and aryl/heteroaryl boronic acids under mild conditions is described. The successful synthesis of highly ortho substituted biaryls and high chemoselectivity of these bench stable intermediates over tosylates, triflates, mesylates, and chlorides increases its scope as a valuable cross-coupling partner. The generality of this protocol was further extended to other boron containing nucleophiles (boronates, trifluoroborates) and alkyl boronic acids.
Joseph, Jayan T.,Sajith, Ayyiliath M.,Ningegowda, Revanna C.,Nagaraj, Archana,Rangappa,Shashikanth, Sheena
supporting information
p. 5106 - 5111
(2015/08/06)

Isopropylation of naphthalene by isopropanol over conventional and Zn- and Fe-modified USY zeolites
Catalytic performances of USY, MOR, and BEA zeolites were compared for the isopropylation of naphthalene by isopropyl alcohol in a high-pressure, fixed-bed reactor. The USY catalyst showed a high conversion of 86% and good stability but a low 2,6-/2,7-DIPN shape selectivity ratio of 0.94. In contrast, over the MOR catalyst, 2,6-DIPN was selectively synthesized with a high 2,6-/2,7-DIPN ratio of 1.75, but low naphthalene conversions and fast deactivation of the catalyst were observed. The USY catalyst was modified by Zn and Fe using the wet impregnation method to enhance the selectivity for 2,6-DIPN. The highest conversion (~95%) and selectivity for 2,6-DIPN (~20%) were achieved with 4% Zn/USY catalyst. It appeared that small metal oxide islands formed in the USY pores to decrease the effective pore size and thus render it mildly shape-selective. Zn loading also decreased the number of strong acid sites responsible for coke formation and increased the number of weak acid sites. The high conversion and stability of Zn-modified catalysts were ascribed to the presence of a suitable admixture of weak and strong acid sites with less coke deposition. The Fe-modified USY catalysts were less effective because the modification increased the number of the strong acid sites.
Banu, Marimuthu,Lee, Young Hye,Magesh, Ganesan,Lee, Jae Sung
p. 120 - 128
(2014/01/06)

Palladium-catalysed direct cross-coupling of secondary alkyllithium reagents
Palladium-catalysed cross-coupling of secondary C(sp3) organometallic reagents has been a long-standing challenge in organic synthesis, due to the problems associated with undesired isomerisation or the formation of reduction products. Based on our recently developed catalytic C-C bond formation with organolithium reagents, herein we present a Pd-catalysed cross-coupling of secondary alkyllithium reagents with aryl and alkenyl bromides. The reaction proceeds at room temperature and on short timescales with high selectivity and yields. This methodology is also applicable to hindered aryl bromides, which are a major challenge in the field of metal catalysed cross-coupling reactions.
Vila, Carlos,Giannerini, Massimo,Hornillos, Valentin,Fananas-Mastral, Martin,Feringa, Ben L.
p. 1361 - 1367
(2014/03/21)

Beyond benzyl grignards: Facile generation of benzyl carbanions from styrenes
Benzylic functionalization is a convenient approach towards the conversion of readily available aromatic hydrocarbon feedstocks into more useful molecules. However, the formation of carbanionic benzyl species from benzyl halides or similar precursors is far from trivial. An alternative approach is the direct reaction of a styrene with a suitable coupling partner, but these reactions often involve the use of precious-metal transition-metal catalysts. Herein, we report the facile and convenient generation of reactive benzyl anionic species from styrenes. A CuI-catalyzed Markovnikov hydroboration of the styrenic double bond by using a bulky pinacol borane source is followed by treatment with KOtBu to facilitate a sterically induced cleavage of the C-B bond to produce a benzylic carbanion. Quenching this intermediate with a variety of electrophiles, including CO2, CS2, isocyanates, and isothiocyanates, promotes C-C bond formation at the benzylic carbon atom. The utility of this methodology was demonstrated in a three-step, two-pot synthesis of the nonsteroidal anti-inflammatory drug (±)-flurbiprofen. Make or break: The facile generation of benzyl anion equivalents from styrenes has been achieved by using a Cu-catalyzed hydroboration in conjunction with sterically induced cleavage of the C-B bond with tBuOK. Quenching this reactive intermediate with heteroallene electrophiles yields benzylic C-C bond formation (see scheme), and the utility of this methodology has been demonstrated by a synthesis of the nonsteroidal anti-inflammatory drug (±)-flurbiprofen. Copyright
Grigg, R. David,Rigoli, Jared W.,Van Hoveln, Ryan,Neale, Samuel,Schomaker, Jennifer M.
p. 9391 - 9396
(2012/08/29)

Comparison of the catalytic performance of the metal substituted cage type mesoporous silica catalysts in the alkylation of naphthalene
Alkylation of naphthalene with propylene to diisopropylnaphthalenes (DIPN) for the use as a high-quality solvent was carried out over mesoporous AlSBA-1, GaSBA-1 and FeSBA-1 catalysts. The AlSBA-1 and GaSBA-1 catalysts were very active in alkylation while the FeSBA-1 samples, although initially active, deactivated quickly. Activity of the SBA-1 catalysts increased with the amount of Al, Ga or Fe incorporation into the silica framework. Regardless of the alkylation activity, all SBA-1 catalysts showed rather low isomerization activity and as a result low 2,6-DIPN selectivity was observed. The AlSBA-1 and GaSBA-1 catalysts proved to be promising for DIPN solvent synthesis due to their high alkylation activity and stability together with low 2,6-DIPN selectivity.
Brzozowski, Robert,Vinu, Ajayan,Gil, Barbara
experimental part
p. 76 - 82
(2010/08/06)

Shape-selective diisopropylation of naphthalene in H-Mordenite: Myth or reality?
Selective diisopropylation of naphthalene to 2,6-diisopropylnaphthalene is a challenging goal in sustainable catalysis. Ultrastable Y and H-Mordenite zeolites are the best catalysts reported in the literature with respect to 2,6-diisopropylnaphthalene selectivity. It is generally accepted that in the case of H-Mordenite, shape-selectivity is responsible for the observed 2,6-diisopropylnaphthalene selectivity, while on Ultrastable Y-zeolite, the observed selectivity reflects the internal thermodynamic equilibrium of positional isomers. Revisiting both the experimental and the computational work in this field now leads to the conclusion that shape-selectivity of whatever kind can be ruled out in the case of H-Mordenite. H-Mordenite catalysts produce usually a kinetically controlled mixture of diisopropylnaphthalene isomers which can shift to the direction of a thermodynamical distribution at high reaction temperatures or over more active catalysts.
Bouvier, Christophe,Buijs, Wim,Gascon, Jorge,Kapteijn, Freek,Gagea, Bogdan C.,Jacobs, Pierre A.,Martens, Johan A.
scheme or table
p. 60 - 66
(2010/06/19)

Dialkylation of naphthalene with isopropanol over H3PO 4/MCM-41 Catalysts for the environmentally friendly synthesis of 2,6-dialkylnaphthalene
AlMCM-41 materials with SiO2/Al2O3 molar ratios 20, 70, 110, 150, 200, and Si-MCM-41 were synthesized following standard procedures, and loaded with different amounts of H3PO4. The catalysts were well
Ghiaci,Aghabarari,Rives,Vicente,Sobrados,Sanz
experimental part
p. 141 - 149
(2010/08/20)

Lithium naphthalenide-induced reductive alkylation and addition of aryl-and heteroaryl-substituted dialkylacetonitriles
Lithium naphthalenide (LN)-induced reductive alkylation/addition reactions of aryl-, pyridyl-, and 2-thienyl-substituted dialkylacetonitriles have been investigated. Upon treatment with LN in THF at -40°C, both aryl and pyridyl precursors could undergo the reductive decyanation smoothly, and the in situ generated carbanions could be readily trapped by alkyl halides, ketones, aldehydes, or even oxygen to afford a wide range of functionalized aromatic derivatives bearing a newly established quaternary carbon. To effect the desired reductive alkylation of 2-thienyldialkylacetonitriles, a much lower temperature such as -100°C was required. Also with these substrates, an interesting ring-opening/S-alkylation process was observed when the reductive alkylation were performed at -78°C to give 1-alkylsulfanyl-1,3,4-trienes. A mechanistic discussion is given for this observation.
Tsao, Jing-Po,Tsai, Ting-Yueh,Chen, I-Chia,Liu, Hsing-Jang,Zhu, Jia-Liang,Tsao, Sheng-Wei
experimental part
p. 4242 - 4250
(2011/02/25)

Microwave-assisted regioselective alkylation of naphthalene compounds using alcohols and zeolite catalysts
Regioselective alkylation of naphthalene compounds with alcohols smoothly proceeded in the presence of zeolite catalysts under microwave irradiation. A H-mordenite (H-M) zeolite catalyst (SiO2/Al2O3 ratio = 240) showed the highest efficiency. In the microwave reactions, high reaction rates and high selectivities for 2,6-dialkylnaphthalenes were achieved. In the best case for the reaction of 2-isopropylnaphthalene with isopropyl alcohol, the conversion and the selectivity were 43.5% and 66.4%, respectively. In di-tert-butylation of naphthalene with tert-butyl alcohol, the conversion and the selectivity reached 86.5% and 70.4%, respectively. The conversions and the selectivities were generally higher than those obtained by conventional oil bath heating.
Yamashita, Hiroshi,Mitsukura, Yumi,Kobashi, Hiroko,Hiroki, Kazuaki,Sugiyama, Jun-ichi,Onishi, Kiyotaka,Sakamoto, Tetsuo
experimental part
p. 145 - 149
(2010/08/20)

Regioselective arene functionalization: Simple substitution of carboxylate by alkyl groups
Arenes with various alkyl side-chains were synthesized in high yields and excellent regioselectivities. Starting from toluic and naphthoic acids, the carboxylate group was conveniently substituted by alkyl halides by Birch reduction and subsequent decarbonylation. The method is characterized by inexpensive starting materials and reagents, and methylation of arenes was realized. Besides simple alkyl substituents, the scope of arene functionalization was extended by benzyl, fluoro, amino, and ester groups. We were able to control the alkylation of 1-naphthoic acid during Birch reduction by the addition of tert-butanol. This allowed the regioselective synthesis of mono and bis-substituted naphthalenes from the same starting material.
Krueger, Tobias,Vorndran, Katja,Linker, Torsten
experimental part
p. 12082 - 12091
(2010/05/17)

The alkylation of naphthalene over one-dimensional fourteen-membered ring zeolites. the influence of zeolite structure and alkylating agent on the selectivity for dialkylnaphthalenes
The alkylation, i.e., isopropylation, s-butylation, and t-butylation, of naphthalene (NP) was examined over one-dimensional fourteen-membered (14-MR) zeolites: CIT-5 (CF1), UTD-1 (DON), and SSZ-53 (SFH), and compared to the results over H-mordenite (MOR)
Sugi, Yoshihiro,Maekawa, Hiroyoshi,Naiki, Hiroaki,Komura, Kenichi,Kubota, Yoshihiro
experimental part
p. 1166 - 1174
(2009/05/06)

Isopropylation of naphthalene by isopropyl alcohol over USY catalyst: An investigation in the high-pressure fixed-bed flow reactor
Catalytic performances of USY, H-mordenite, dealuminated H-mordenite, and H-MCM-22 zeolite catalysts in the isopropylation of naphthalene by isopropyl alcohol with decalin or cyclohexane as a solvent were compared in a high-pressure fixed-bed flow reactor. For the USY catalyst, reaction conditions, such as reaction temperature and pressure, reactant ratio and space velocity, and solvent concentration and type, were controlled to investigate in detail the effect of reaction conditions on the catalytic activity. Over H-mordenite, it was found that 2,6-diisopropylnaphthalene (2,6-DIPN) could be selectively synthesized with a 2,6-/2,7-DIPN ratio of 2.46, and dealumination could enhance not only the selectivity of 2,6-DIPN, with a 2,6-/2,7-DIPN ratio of 2.67, but also the conversion of naphthalene, which was 27.4%, three times as high as that over the unmodified one at 6 h of reaction time on stream. However, neither the H-mordenite or the dealuminated one were catalytically stable and the selectivity of DIPN was at a very low level of less than 12%. In contrast, over the USY catalyst, a high and stable conversion of about 90%, a high selectivity of DIPN of more than 40%, and a considerable 2,6-/2,7-DIPN ratio of 1.46 could be achieved by adjusting the reaction conditions, although no shape selectivity was observed on USY. On the other hand, only a low 2,6-/2,7-DIPN ratio of 0.47 with a low conversion of about 30% was revealed over H-MCM-22, which indicates that the reaction takes place on the external surface of this zeolite. An attempt has been made to explain the catalytic activity, selectivity, and stability in relation to the zeolite structures, product properties, and reaction conditions.
Wang, Jun,Park, Jung-Nam,Park, Yong-Ki,Lee, Chul Wee
p. 265 - 272
(2007/10/03)

Zeolite pore entrance effect on shape selectivity in naphthalene isopropylation
Naphthalene alkylation with propylene was studied over various large-pore zeolites and also over amorphous aluminosilicate catalysts. Isomeric distribution of isopropylnaphthalenes (IPN) and diisopropylnaphthalenes (DIPN) were compared at different temperatures. The shape-selectivity effect that occurred in the entrances to the pores could be responsible for high α-selectivity in monoisopropylation and 1NR-selectivity in diisopropylation observed in the naphthalene alkylation over wide pore zeolites. The product was then relatively rich in 1-IPN, 1,3-DIPN, and 1,4-DIPN. This type of shape selectivity suppressed other shape-selectivity effects, e.g., high β-selectivity of reactions occurring inside channels or cavities of the zeolite. High concentration of TIPN in alkylation products could be explained superbly with the help of catalysis in pore entrances. The explanation of such results was proposed to be a specific shape-selectivity effect of alkylation reaction occurring in the entrances to the pores of zeolite.
Brzozowski,Skupinski
p. 313 - 318
(2007/10/03)

Novel synthesis of pentacarbonylbenzopyranylidenetungsten(0) complexes and their Diels - Alder reaction with electron-rich alkenes [11]
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Iwasawa,Shido,Maeyama,Kusama
p. 10226 - 10227
(2007/10/03)

Friedel-crafts alkylation and acylation in the absence of solvent
A short and efficient synthetic route, for alkylation and acylation of aromatic compounds in the absence of solvent is developed. According to the reaction system and conditions used, different alkyl-, and acyl arenes are obtained in moderate to good yields. The structures are assigned by 1H and 13C NMR spectroscopy.
Ghiaci,Asghari
p. 2213 - 2220
(2007/10/03)

Enantioselective biotransformation of 1-isopropylnaphthalene in rabbits
1-isopropylnaphthalene (1) was administered orally to rabbits and the following eight metabolites, 2-(1-naphthyl)-2-propanol (7), 2-(1-naphthy)-1-propanol (8: R/S = 83 :17), 2-(1-naphthyl)-1,2-propanediol (9: R/S = 40:60), 4-isopropyl-1,2-naphthoquinone (10), 4-isopropyl-1-naphthol (11), 4-isopropyl-2-naphthol (12), 5-isopropyl-2-naphthol (13), and 2-(1-naphthyl)propanoic acid (14') as its methyl ester (14: R/S = 52:48), were isolated from urine. Among them, three metabolites (8, 9, and 14), possessing an asymmetric carbon atom in the molecule, were formed enantioselectively and five metabolites (7, 10, 11, 12, and 13) were formed regioselectively. The presumed metabolic pathways of 1-isopropylnaphthalene (1) in rabbits leading to these metabolites are discussed.
Matsumoto,Ishida,Takeda,Soh,Kubo,Sakamoto
p. 216 - 222
(2007/10/02)

Reduction of Monobenzylic Alcohols with Sodium Borohydride/Trifluoroacetic Acid
Sodium borohydride/trifluoroacetic acid readily effects the reduction of monobenzylic alcohols to afford the corresponding hydrocarbons in moderate to high yields.
Nutaitis, Charles F.,Bernardo, Joseph E.
p. 487 - 493
(2007/10/02)

Kinetics and Regioselectivity of the Autoxidation of o-Substituted Isopropyl Aromatics
The relative chain propagation constants and the regioselectivities of the oxidations of o-cymene and 2-isopropyl-1,4-dimethylbenzene were determined by competitive oxidations of the hydrocarbons with cumene.As expected, the reactivity of the tertiary C-H bond of the isopropyl group is considerably decreased by o-methyl groups.Also in α-isopropylnaphthalene a considerable decrease in the reactivity of the tertiary C-H bond takes place.The decrease of the chain propagation constants effects a decrease of the oxidabilities of o-substituted isopropyl aromatics.In the case of the methyl isopropyl benzenes the increase of the chain termination constants by primary peroxy radicals must also be taken into consideration.This results in a decrease of the oxidabilities which can be observed even in p-cymene (in comparison with cumene).
Heinze, Antje,Lauterbach, Gerlinde,Pritzkow, Wilhelm,Schmidt-Renner, Wolfgang,Voerckel, Volkmar,Zewegsuren, Nansadyn
p. 439 - 446
(2007/10/02)

PRODUCTS OF THE CHLORINATION OF 1-ALKYLNAPHTHALENES WITH SULPHURYL CHLORIDE
The reactions of sulphuryl chloride with some 1-alkylnaphthalenes are described and discussed.
Calvert, David J.,Mare, Peter B. D. de la,Ogawa, Takuji,Yamamoto, Hidetoshi,Suzuki, Hitomi
p. 357 - 362
(2007/10/02)

THERMAL HETEROCYCLIZATION OF METHYL ARYL KETAZINES. REACTIONS OF THE TAUTOMERIC ENEHYDRAZINE FORM
Over the temperature range 220-280 deg C the thermal reactions of methyl aryl ketazines (Ar=C6H5-, 4-CH3C6H4-, 4-CH3OC6H4-, and α-naphthyl-) proceed with their cyclization to give pyrazoline and benzodiazepine derivatives.With an increase in temperature to 320-350 deg C the subsequent transformations of these compounds lead to the formation of substituted pyrazoles, 1-methyl-1,2-diarylcyclopropanes isomeric olefins, low-molecular-weight aromatic hydrocarbons, and isoquinolines.
Shurukhin, Yu. V.,Klyuev, N. A.,Grandberg, I. I.
p. 723 - 732
(2007/10/02)

Regioselective preparation of β-isopropylnaphthalene over superacidic solid or supported perfluorinated sulfonic acid catalysts
A process for the production of β-isopropylnaphthalene in high regioselectivity (90-98%) by alkylation of naphthalene over solid or supported superacid catalysts, such as a perfluorinated alkanesulfonic acid of four to eighteen carbon atoms (C4 F9 SO3 H to C18 F37 SO3 H) or a polymeric perfluorinated resin-sulfonic acid, such as the acid form of the commercially available Nafion-K ion-membrane resin (DuPont). Further isomerization of mixtures of isomeric isopropylnaphthalenes to preferentially pure β-isopropylnaphthalene can also be effected.
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(2008/06/13)

Sulfonation of aromatic compounds in the presence of solvents
A process for the sulfonation of aromatic compounds wherein an aromatic substance consisting of one or more aromatic compounds susceptible to the action of sulfur trioxide is formed into a reactant by admixture with one or more organic liquids, substantially inert to sulfur trioxide under the conditions of the process, which reactant is brought to boiling at a temperature not greater than 100° C under a pressure of from 0.1 mm Hg to atmospheric pressure, gaseous sulfur trioxide is introduced thereinto thereby causing it to continue to boil, the component or components of the reactant thus volatilized is or are reconverted to liquid in a heat-exchanger and recycled to the reaction chamber, and the pressure in the reaction chamber and the rate at which the gaseous sulfur trioxide is introduced into the reactant are controlled so as to ensure that there is always present in the reaction chamber an amount of volatilizable matter exceeding that amount volatilizable by the heat of reaction of the aromatic substance present in the reaction chamber with the gaseous sulfur trioxide in contact with said aromatic substance and that the temperature of the reaction mixture is a temperature of 100° C or below.
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(2008/06/13)