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3-Aryloxindole derivatives were synthesized through a Friedel-Crafts-type cyclization. The reaction was catalyzed by a trimethylsilyl tricyanopalladate complex generated in situ from trimethylsilyl cyanide and Pd(OAc)(2). Wide varieties of diethyl phosphates derived from N-arylmandelamides were converted almost quantitatively into oxindoles. When N,N-dibenzylamide was used instead of an anilide substrate, a benzo-fused delta-lactam was obtained. An oxindole product was subjected to substitution reactions to afford 3,3-diaryloxindoles with two different aryl groups.

3-Aryloxindole derivatives were synthesized through a Friedel-Crafts-type cyclization. The reaction was catalyzed by a trimethylsilyl tricyanopalladate complex generated in situ from trimethylsilyl cyanide and Pd(OAc)(2). Wide varieties of diethyl phosphates derived from N-arylmandelamides were converted almost quantitatively into oxindoles. When N,N-dibenzylamide was used instead of an anilide substrate, a benzo-fused delta-lactam was obtained. An oxindole product was subjected to substitution reactions to afford 3,3-diaryloxindoles with two different aryl groups.

Hyper-crosslinked polymers (HCPs) have been produced by the Friedel-Crafts reaction using anthracene, benzene, carbazole or dibenzothiophene as precursors and dimethoxymethane as crosslinker, and the effect of graphene oxide (GO) addition has been studied. The resulting HCPs were highly microporous with BET areas (ABET) between 590 and 1120 m2g-1. The benzene-derived HCP (B1FeM2) and the corresponding composite with GO (B1FM2-GO) exhibited the highest ABET and were selected to study their hydrogen adsorption capacities in the pressure range of 0.1 - 14 MPa at 77 K. The maximum H2 excess uptake was 2.1 and 2.0 wt% for B1FeM2 and B1FeM2-GO, respectively, at 4 MPa and 77 K. The addition of GO reduced the specific surface area but increased the density of the resultant HCP-GO composites, which is beneficial for practical applications and proves that materials giving higher gravimetric storage capacities are not necessarily those that offer higher volumetric capacities. H2 adsorption-desorption cycles up to 14 MPa showed irreversible deformation of both HCP and HCP-GO materials, which calls into question their application for hydrogen adsorption at pressures above 4 MPa.

Tetraarylmethanes are a class of organic molecules defined by a central carbon bonded to four aryl substituents. Due to the highly-conjugated structure of these molecules (and three dimensionality), tetraarylmethanes are important in industrial applications such as synthetic dyes, organic-LEDs, organic solar cells, and even medically in drug delivery. Chiral tetraarylmethanes have four different aryl substituents bonded to the central carbon. While these chiral molecules are of interest due to the unique properties they could possess from their chirality, no synthesis of them has been reported. In this project, we have made progress in the development of a model system for the synthesis of chiral tetraarylmethanes that can be expanded to encompass a variety of substrates and substituents. With 2-methoxyphenol as our starting material, we have developed a procedure to synthesize a precursor to chiral teraarylmethanes.

We successfully demonstrated that Friedel−Crafts‐type allylation of phenol derivatives and allylic phosphates is catalyzed by the AgTFA/trimethylsilyl cyanide (Me3SiCN) and Pd(OAc)2/Me3SiCN combined systems to afford the C‐allylated product in a highly regioselective manner. The corresponding silyl cyanometallates generated in situ are proposed to be the active catalytic species. Lewis acidity of the reversibly formed ion pairs is appropriately regulated for this reaction. The para‐allylated anisole and phenol derivatives are selectively obtained. The para‐substituted ones are converted to the ortho‐allylated products. The reactivity of the catalytic systems is strongly dependent on the electronic nature of both electrophile and nucleophile. Substitution of an aromatic ring on the allylic phosphate is essential for the reaction. Thus, the competitive reaction of a 1 : 1 mixture of cinnamyl and simple allyl phosphates affords only the cinnamyl‐substituted product.

We successfully demonstrated that Friedel−Crafts‐type allylation of phenol derivatives and allylic phosphates is catalyzed by the AgTFA/trimethylsilyl cyanide (Me3SiCN) and Pd(OAc)2/Me3SiCN combined systems to afford the C‐allylated product in a highly regioselective manner. The corresponding silyl cyanometallates generated in situ are proposed to be the active catalytic species. Lewis acidity of the reversibly formed ion pairs is appropriately regulated for this reaction. The para‐allylated anisole and phenol derivatives are selectively obtained. The para‐substituted ones are converted to the ortho‐allylated products. The reactivity of the catalytic systems is strongly dependent on the electronic nature of both electrophile and nucleophile. Substitution of an aromatic ring on the allylic phosphate is essential for the reaction. Thus, the competitive reaction of a 1 : 1 mixture of cinnamyl and simple allyl phosphates affords only the cinnamyl‐substituted product.

Tetraarylmethanes are a class of organic molecules defined by a central carbon bonded to four aryl substituents. Due to the highly-conjugated structure of these molecules (and three dimensionality), tetraarylmethanes are important in industrial applications such as synthetic dyes, organic-LEDs, organic solar cells, and even medically in drug delivery. Chiral tetraarylmethanes have four different aryl substituents bonded to the central carbon. While these chiral molecules are of interest due to the unique properties they could possess from their chirality, no synthesis of them has been reported. In this project, we have made progress in the development of a model system for the synthesis of chiral tetraarylmethanes that can be expanded to encompass a variety of substrates and substituents. With 2-methoxyphenol as our starting material, we have developed a procedure to synthesize a precursor to chiral teraarylmethanes.

[EN] An organocatalytic enantioselective functionalization in the carbocyclic ring of indoles with benzoxathiazine 2,2-dioxides is described using a quinine-derived bifunctional organocatalyst. This aza-Friedel-Crafts reaction provides 4-indolyl, 5-indolyl and 7-indolyl sulfamidate derivatives in good yields (up to 99%) and with moderate to high enantioselectivities (up to 86% ee).

[EN] A highly enantioselective addition of hydroxyquinolines to isatin-derived ketimines has been realized using a quinine-derived thiourea organocatalyst. The reaction affords chiral 3-amino-2-oxindoles bearing a quinoline moiety with a quaternary stereocenter in high yields (up to 98%) and excellent enantioselectivities (up to 99%). Moreover, we can extend this methodology for the enantioselective functionalization of 5-hydroxyisoquinoline. This methodology represents, to the best of our knowledge, the first enantioselective addition of hydroxyquinolines to imines.

[EN] A highly enantioselective addition of hydroxyquinolines to isatin-derived ketimines has been realized using a quinine-derived thiourea organocatalyst. The reaction affords chiral 3-amino-2-oxindoles bearing a quinoline moiety with a quaternary stereocenter in high yields (up to 98%) and excellent enantioselectivities (up to 99%). Moreover, we can extend this methodology for the enantioselective functionalization of 5-hydroxyisoquinoline. This methodology represents, to the best of our knowledge, the first enantioselective addition of hydroxyquinolines to imines.

This thesis describes the development of a general method for the synthesis of tetraarylmethanes using an excisable sulfur latch. Triarylcarbinols, easily prepared in two steps from commercially available reagents, are cyclized via an intramolecular Friedel-Crafts arylation in the presence of catalytic Bi(OTf)3. The resulting 9-aryl-9-phenylthioxanthenes are then desulfurized over Raney nickel to afford the corresponding tetraarylmethanes in high to moderate yields. Tetraarylmethanes are important structural components in many organic light-emitting diodes (OLEDs), organic solar cells (OPVs), and many hydrogen fuel cells. These compounds are also candidates for drug transport and are beginning to see use as probes in chemical biology.

This thesis describes the development of a general method for the synthesis of tetraarylmethanes using an excisable sulfur latch. Triarylcarbinols, easily prepared in two steps from commercially available reagents, are cyclized via an intramolecular Friedel-Crafts arylation in the presence of catalytic Bi(OTf)3. The resulting 9-aryl-9-phenylthioxanthenes are then desulfurized over Raney nickel to afford the corresponding tetraarylmethanes in high to moderate yields. Tetraarylmethanes are important structural components in many organic light-emitting diodes (OLEDs), organic solar cells (OPVs), and many hydrogen fuel cells. These compounds are also candidates for drug transport and are beginning to see use as probes in chemical biology.

Enamides with a free NH group have been evaluated as nucleophiles in chiral Bronsted acid-catalyzed enantioselective alpha-amidoalkylation reactions of bicyclic hydroxylactams for the generation of quaternary stereocenters. A quantitative structure-reactivity relationship (QSRR) method has been developed to find a useful tool to rationalize the enantioselectivity in this and related processes and to orient the catalyst choice. This correlative perturbation theory (PT)-QSRR approach has been used to predict the effect of the structure of the substrate, nucleophile, and catalyst, as well as the experimental conditions, on the enantioselectivity. In this way, trends to improve the experimental results could be found without engaging in a long-term empirical investigation.

Enamides with a free NH group have been evaluated as nucleophiles in chiral Bronsted acid-catalyzed enantioselective alpha-amidoalkylation reactions of bicyclic hydroxylactams for the generation of quaternary stereocenters. A quantitative structure-reactivity relationship (QSRR) method has been developed to find a useful tool to rationalize the enantioselectivity in this and related processes and to orient the catalyst choice. This correlative perturbation theory (PT)-QSRR approach has been used to predict the effect of the structure of the substrate, nucleophile, and catalyst, as well as the experimental conditions, on the enantioselectivity. In this way, trends to improve the experimental results could be found without engaging in a long-term empirical investigation.

Enamides with a free NH group have been evaluated as nucleophiles in chiral Bronsted acid-catalyzed enantioselective alpha-amidoalkylation reactions of bicyclic hydroxylactams for the generation of quaternary stereocenters. A quantitative structure-reactivity relationship (QSRR) method has been developed to find a useful tool to rationalize the enantioselectivity in this and related processes and to orient the catalyst choice. This correlative perturbation theory (PT)-QSRR approach has been used to predict the effect of the structure of the substrate, nucleophile, and catalyst, as well as the experimental conditions, on the enantioselectivity. In this way, trends to improve the experimental results could be found without engaging in a long-term empirical investigation.

An organocatalytic enantioselective Friedel–Crafts alkylation of a series of substituted 1- naphthol derivatives and activated phenols with ethyl trifluoropyruvate, catalyzed by a quinine-derived squaramide, is presented. Good yields and high to excellent enantioselectivities of the Friedel– Crafts alkylation products were obtained.

An organocatalytic enantioselective Friedel–Crafts alkylation of a series of substituted 1- naphthol derivatives and activated phenols with ethyl trifluoropyruvate, catalyzed by a quinine-derived squaramide, is presented. Good yields and high to excellent enantioselectivities of the Friedel– Crafts alkylation products were obtained.

Simple and stereocontrolled preparation of benzoylated phenylalanine derivatives from optically pure phenylalanine using Friedel-Crafts reaction in trifluoromethanesulfonic acid (TfOH) is reported; these derivatives are useful for photoaffinity labeling. Protected or unprotected phenylalanine derivatives were converted to benzoyl derivatives in TfOH at room temperature in a short time without loss of optical purity. The reaction condition was applied to synthesize novel photoreactive phenylalanine derivative, which has two photophores (benzophenone and diazirine). The detail analysis of photo-irradiation for two different photophores contained phenylalanine derivative was also investigated.

Simple and stereocontrolled preparation of benzoylated phenylalanine derivatives from optically pure phenylalanine using Friedel-Crafts reaction in trifluoromethanesulfonic acid (TfOH) is reported; these derivatives are useful for photoaffinity labeling. Protected or unprotected phenylalanine derivatives were converted to benzoyl derivatives in TfOH at room temperature in a short time without loss of optical purity. The reaction condition was applied to synthesize novel photoreactive phenylalanine derivative, which has two photophores (benzophenone and diazirine). The detail analysis of photo-irradiation for two different photophores contained phenylalanine derivative was also investigated.

Simple and stereocontrolled preparation of benzoylated phenylalanine derivatives from optically pure phenylalanine using Friedel-Crafts reaction in trifluoromethanesulfonic acid (TfOH) is reported; these derivatives are useful for photoaffinity labeling. Protected or unprotected phenylalanine derivatives were converted to benzoyl derivatives in TfOH at room temperature in a short time without loss of optical purity. The reaction condition was applied to synthesize novel photoreactive phenylalanine derivative, which has two photophores (benzophenone and diazirine). The detail analysis of photo-irradiation for two different photophores contained phenylalanine derivative was also investigated.

We report here a novel synthesis of optically active bishomotyrosine. The bishomotyrosine skeleton was constructed by using a Friedel-Crafts reaction between phenol and optically active N-Tfa-Glu(Cl)-OMe in triflic acid under the mild condition. Reduction and subsequent deprotection then afforded bishomotyrosine derivatives without any loss of optical purity.

We report here a novel synthesis of optically active bishomotyrosine. The bishomotyrosine skeleton was constructed by using a Friedel-Crafts reaction between phenol and optically active N-Tfa-Glu(Cl)-OMe in triflic acid under the mild condition. Reduction and subsequent deprotection then afforded bishomotyrosine derivatives without any loss of optical purity.

We report here a novel synthesis of optically active bishomotyrosine. The bishomotyrosine skeleton was constructed by using a Friedel-Crafts reaction between phenol and optically active N-Tfa-Glu(Cl)-OMe in triflic acid under the mild condition. Reduction and subsequent deprotection then afforded bishomotyrosine derivatives without any loss of optical purity.

Effective Friedel-Crafts reactions with 3-(3-methoxyphenyl)-3-(trifluoromethyl)-3H-diazirine and optically active N-TFA-Asp(Cl)-OMe in triflic acid afforded homophenylalanine derivatives effectively without loss of the optical purity.

Effective Friedel-Crafts reactions with 3-(3-methoxyphenyl)-3-(trifluoromethyl)-3H-diazirine and optically active N-TFA-Asp(Cl)-OMe in triflic acid afforded homophenylalanine derivatives effectively without loss of the optical purity.

Effective Friedel-Crafts reactions with 3-(3-methoxyphenyl)-3-(trifluoromethyl)-3H-diazirine and optically active N-TFA-Asp(Cl)-OMe in triflic acid afforded homophenylalanine derivatives effectively without loss of the optical purity.

A novel method has been developped for synthesizing aryl ketones by means of I-2-DMF mediated Friedel Crafts acylation of aromatic substrates. The reaction is applicable to activated aromatic compounds. The present process is carried out under conditions involving minimal wastes and energy-consumption as compared to the use of molecular iodine.

An efficient Friedel-Crafts reaction of TFA-Asp(Cl)-OMe and stoichiometric amounts of benzene was established by using neat trifluoromethanesulfonic acid (TfOH) as solvent and catalyst under a mild condition. This methodology has been applied to many aromatic compounds and enabled synthesis of several homophenylalanine derivatives.

An efficient Friedel-Crafts reaction of TFA-Asp(Cl)-OMe and stoichiometric amounts of benzene was established by using neat trifluoromethanesulfonic acid (TfOH) as solvent and catalyst under a mild condition. This methodology has been applied to many aromatic compounds and enabled synthesis of several homophenylalanine derivatives.

An efficient Friedel-Crafts reaction of TFA-Asp(Cl)-OMe and stoichiometric amounts of benzene was established by using neat trifluoromethanesulfonic acid (TfOH) as solvent and catalyst under a mild condition. This methodology has been applied to many aromatic compounds and enabled synthesis of several homophenylalanine derivatives.

By acylation of 1,2,3,4-tetrahydro-2,2,4,7-tetramethylquinoline under the conditions of the Friedel–Crafts reaction its 6-acetyl derivative was obtained, which opens the access to new linearly designed 6-(pyrimidin-4-yl)-1,2,3,4-tetrahydro-2,2,4,7-tetramethylquinolines. © 2017, Pleiades Publishing, Ltd.