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A new type of molecular wiring method was developed based on the polymerization or copolymerization of an insulated π-conjugated monomer between nanosized electrodes.

Synthesis and characterization of a series of mono-O-(diphenylphosphinobenzyl)calix[6]arenes are presented. The two types of calix[6]arene moieties were prepared: 1 (with tert-butyl groups at the u...

X-ray crystallographic analysis and CPMAS solid-state NMR measurements of tetrakis(diphenylphosphino)calix[4]arene tetramethyl ether (1) elucidated that in the solid-state 1 adopts a flattened partial cone conformation having C1 symmetry. In solution, on the other hand, the 1H, 13C, and 31P NMR spectra measured at −20 °C indicated that 1 has a partial cone conformation with a mirror plane. Two-dimensional 31P EXSY and variable-temperature 31P NMR spectra reveal a fluxional behavior of 1 in solution on the NMR time scale due to annulus rotation from the methoxy side. Concerning the energetics for the four conformers of 1, an ab initio molecular orbital calculation showed that the partial cone conformation is the most stable form, while the cone and the 1,3-alternate conformers are only slightly less stable.

Co2(CO)8-catalyzed ring-opening carbonylation of oxiranes and oxetane smoothly proceeds with high regioselectivity under 1 atm of carbon monoxide at room temperature to give the corresponding β- and γ-siloxy amides in high yields, respectively. [(R3Si)2NR1R2]+[Co(CO)4]− is thought to be an active catalyst species and directs the high regioselectivity of the carbonylation.

Carbonyl compounds were hydrogenated to the corresponding alcohols in excellent yields using formic acid with a ruthenium complex at 125 °C for 3 h. 2-Propanone was reduced to 2-propanol by RuCl2(PPh3)3–HCOOH system in 94% yield with 98% selectivity. 3-Pentanone, cyclohexanone, acetophenone, and propiophenone were hydrogenated to the corresponding alcohols in 86, 78, 84, and 86% yields respectively. The ketone having the bulkier alkyl groups showed lower reactivity. The catalytic activity was found to decrease in the order RuCl2(PPh3)3, RuHCl(PPh3)3, RuHCl(CO)(PPh3)3, and RuH2(PPh3)4.

Nitroarenes are reductively converted into quinoline derivatives with aliphatic alcohols in the presence of a catalytic amount of ruthenium compound at 180 °C. Ruthenium(III) chloride is the most effective catalyst. The reaction of nitrobenzene with 1-propanol and 1-butanol gave 2-ethyl-3-methylquinoline and 3-ethyl-2-propylquinoline in 65 and 70% yields respectively. p-Methoxynitrobenzene gave 3-ethyl-6-methoxy-2-propylquinoline in 70% yield with 1-butanol. The reaction appears to include the redox reaction between the nitroarenes and the alcohols, that is, a catalytic hydrogen transfer reaction which generates the aminoarenes and aldehydes. Thus, the alcohol plays roles as both a reductant and an aldehyde precursor.

Amides reacted with primary alcohols in the presence of a catalytic amount of RuCl2(PPh3)3 at 180 °C to give the corresponding N-monoalkyl amides in fairly good yields. Thus, benzamide reacted with 1-octanol to give N-octylbenzamide in 76% yield with excellent product selectivity. Little esterification of amides with alcohols occurred and selectivity to the N-alkylation was high. Most of the amides gave N-monoalkyl amides but no N,N-dialkyl amides. But formamide reacted with 1-butanol to give N,N-dibutylformamide, as well as N-butylformamide, in low yield. RuCl2(PPh3)3 was the most effective catalyst for this reaction and RuHCl(PPh3)3 also had some catalytic activity.

Various nitroarenes having chloro, methyl, or methoxy substituents were reduced to the corresponding aminoarenes in high yields using formic acid in the presence of a catalytic amount of RuCl2(PPh3)3. For example, 4-chloronitrobenzene was converted in 99% conversion with 98% selectivity at 125 °C for 5 h. 4-Nitroacetophenone was reduced chemoselectively to 1-(4-nitrophenyl)ethanol in 74% isolated yield under the same reaction conditions. Formic acid could also be employed as reductant for hydrogenation of heterocyclic compounds such as quinoline, indole, and quinoxaline in the presence of the ruthenium catalyst. 2-Methylquinoline was hydrogenated to 1,2,3,4-tetrahydro-2-methylquinoline in 93% conversion with 100% selectivity.

The platium catalyst combined with triphenylphosphine, tin(IV) chloride, and triethylamine showed high activity for the reductive N-carbonylation of nitroarene in ethanol at 180 °C under carbon monoxide of 60 kg cm−2. From nitrobenzene, ethyl phenylcarbamate was obtained in 83% yield. Iron(III) chloride, aluminum chloride and titanium(IV) chloride could be used as Lewis acids in place of tin(IV) chloride. Various nitroarenes were transformed into corresponding carbamate in moderate to excellent yields with the platinum catalyst.

Aminoarenes reacted with 2-propen-1-ol and 2-buten-1-ol at 180 °C to give quinoline derivatives in fairly good yields in the presence of a catalytic amount of a ruthenium complex. Dichlorotris(trip...

The catalytic N-alkylation and N-heterocyclization of nitroarenes occur at 180 °C under a carbon monoxide pressure of 70 atm and in the presence of aldehyde and such transitionmetal complexes as rh...

The Catalytic N-heterocyclization of aminoarenes and dinitroarenes using aliphatic n-C3–C5 aldehydes was carried out at 180 °C under the pressure of carbon monoxide (70 atm at room temperature) in the presence of RhCl(PPh3)3 and PdCl2 as a binary catalyst system. The reaction of p-nitroaniline with propanal, butanal, and pentanal gave 3,8-diethyl-2,9-dimethyl-4,7-phenanthroline, 2,9-diethyl-3,8-dipropyl-4,7-phenanthroline, and 3,8-dibutyl-2,9-dipropyl-4,7-phenantroline in 43, 57, and 54% yields respectively. On the other hand, m-nitroaniline and o-nitroaniline gave 1,7-phenanthroline and imidazole derivatives in rather low yields (21 and 24%) under the reaction conditions employed.

1,3-Dioxolane reacted with electron-deficient alkenes, such as diethyl maleate, maleic anhydride, diethyl fumarate and fumaronitrile, under an oxygen atmosphere or in air to give 1:1 adducts in good to excellent yields. The presence of oxygen promoted the reaction. The reaction appears to be characteristic of 1,3-dioxolane. Methylal and ethylal did not react with diethyl maleate under the same conditions.

Dichlorobis(triphenylphosphine) platinum(II) shows good catalytic activity for the reductive N-carbonylation of dinitroarenes in ethanol in the presence of a Lewis acid and triethylamine. From 2,4-dinitrotoluene, diethyl 4-methyl-1,3-phenylenebiscarbamate is obtained in 50% yield at 190°C under carbon monoxide pressure of 60 kg cm−2.