Katsuya Maeyama

Synthesis of sequentially controlled isomeric, wholly aromatic polyketones composed of 2-trifluoromethylbiphenylene and 2,2′-dimethoxybiphenylene units

Abstract The syntheses of three isomeric, wholly aromatic polyketones composed of a trifluoromethylated biphenylene unit and a 2,2′-dimethoxybiphenylene unit were performed via direct electrophilic aromatic acylation polycondensation of finely designed monomers. The two isomers of sequentially controlled wholly aromatic polyketones, i.e. the head-to-tail and head-to-head isomers, composed of 2-trifluoromethyl-4,4′-biphenylene and 2,2′-dimethoxy-5,5′-biphenylene units were synthesized successfully. Furthermore, treatment of 2-trifluoromethylbiphenylene-4,4′-dicarboxylic acid and 2,2′-dimethoxybiphenyl with P 2 O 5 –MsOH gave another isomeric polyketone having a random sequence.

Synthesis of aromatic poly(ether ketone)s having adhesion property to steel surface

Abstract Aromatic copoly(ether ketone)s composed of 5′-(2′-methoxyphenylen)oxy-4-phenylenecarbonyl and 4″-phenylenoxy-4′-phenylenoxy-4-phenylenecarbonyl units were successfully synthesized via P 2 O 5 -MsOH-mediated direct polycondensation of the corresponding carboxylic acids, i.e., 4-(2-methoxyphenoxy)benzoic acid and 4-(4-phenoxyphenoxy)benzoic acid. The aromatic copoly(ether ketone)s bearing methoxy groups thus obtained have prominent adhesion property to steel surface with good thermal stability and high glass transition temperature.

P2O5–MsOH Mediated Regioselective Diaroylation of 2,2′‐Dimethoxy‐1,1′‐binaphthyl

Abstract Phosphorus pentoxide–methanesulfonic acid (P2O5–MsOH) mediated electrophilic aromatic substitution diaroylation of 2,2′‐dimethoxy‐1,1′‐binaphthyl (1) with several aromatic carboxylic acids (3) proceeds to afford 6,6′‐diaroylated adducts (4) as single regioisomers.

NICKEL/ZINC-MEDIATED SYNTHESIS OF AROMATIC NITRILES FROM AROMATIC OXIME ETHERS

ABSTRACT Treatment of o-alkoxybenzaldoxime ethers 3 with an equimolar amount of NiCl2 and 3 equimolar amounts of Zn gave o-alkoxybenzonitriles 4 in good yields. It is suggested that the reaction proceed via coordination of the ether oxygen atom of alkyl ether moiety to low-valent metal species.

NICKEL/ZINC-MEDIATED ALKYL CARBON-OXYGEN BOND CLEAVAGE OF ALKYL ARYL ETHERS

Alkyl carbon-oxygen bonds of alkyl aryl ethers bearing suitable coordination sites were efficiently cleaved by treatment with nickel(II) chloride and zinc in p-xylene under neutral conditions.

Synthesis of Rigid and Optically Active Bis(binaphthyl) Cyclic Compounds

Abstract Optically active cyclic bis(binaphthyl)s (4a–d), which are composed of aromatics, ethers, and ketonic carbonyls, were synthesized through a two‐step nucleophilic aromatic substitution reaction. Bis(binaphthyl) cyclic compounds (4a and 4b) were obtained in moderate yields when difluoride 3a and 3b were employed. On the other hand, bis(binaphthyl)s 4c and 4d were scarcely obtained when 3c and 3d were employed.

Facile Synthesis of 2,2′‐Dialkylated 4,4′‐Oxybiphenols

Abstract 2,2′‐Alkyl‐disubstituted 4,4′‐oxybiphenols (4) were prepared in good yields through esterification of 4,4′‐oxybiphenol (1), AlCl3‐promoted Fries rearrangement, and AlCl3/NaBH4‐promoted reduction reaction.

CHEMOSPECIFICITY IN ARYLATIONS OF δ- AND γ-KETOCARBOXYLIC ACIDS WITH P2O5–MsOH, TfOH, AND RELATED ACIDIC MEDIA

ABSTRACT Remarkable contrast between chemospecificities in acid-mediated arylation of δ- and γ-ketocarboxylic acids was revealed: in the presence of P2O5–MsOH, TfOH, PPA, and MsOH, arylation of δ-ketocarboxylic acid 1A with arenes takes place at the carboxycarbonyl carbon, while that of γ-ketocarboxylic acid 1B takes place at the ketone carbonyl carbon, specifically.

Synthesis of Optically Active Aromatic Ether Ketone Macrocycles Containing 2,2′-Dimethoxy-1,1′-binaphthyl-6,6′-diyl Moieties

Abstract Optically active aromatic ether ketone macrocycles containing 2,2′-dimethoxy-1,1′-binaphthyl-6,6′-diyl moieties were synthesized through electrophilic aromatic substitution reaction and stepwise nucleophilic aromatic substitution reactions. Structures of the resulting macrocycles were confirmed by NMR and matrix assisted laser desorption/ionization time of flight (MALDI-TOF) mass measurements.

Copolymerization of styrene derivatives and cycloolefin with Ni compound/MAO catalyst

Copolymerization of styrene derivatives, such as 4-tert-butylstyrene (4TBS), 4-methylstyrene (4MS), 4-methoxystyrene (4MOS), 4-bromostyrene (4BS), and 5-ethylidene-2-norbomene (ENB) was conducted with nickel (Ni) compound/methylaluminoxane (MAO) catalysts. Polymerization behaviors and properties of the resulting copolymers were investigated. Nickel bis(acetylacetonate) (1) / MAO showed the highest activity. Tg values of the obtained copolymers reached to ca. 300 °C.