Although azomethine ylides have been fully exploited as versatile reactive intermediates in dipolar cycloaddition reactions to construct a variety of heterocyclic compounds involving a nitrogen atom, little is known about their structural and electronic properties. Here a method is developed for the preparation, isolation and characterization of a stable 2-azaphenalenyl based azomethine ylide. N-Phenyl-5,8-di-t-butyl-2-azaphenalenyl cannot be isolated because it undergoes rapid dimerization by CC bond formation at the 1 and 3 positions. In contrast, sterically bulkier N-2,6-di(isopropyl)phenyl-5,8-di-t-butyl-2-azaphenalenyl can be generated and isolated as deep green crystals under deoxygenated conditions. X-ray crystal analysis of this stable azomethine ylide reveals that its azaphenalenyl skeleton has very small bond alternation and structural deformation. The results of spectroscopic and electrochemical theoretical studies indicate that N-2,6-di(isopropyl)phenyl-5,8-di-t-butyl-2-azaphenalenyl has electronic features that are similar to those of phenalenyl anion and it possesses an extremely high HOMO energy.

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We attempted to prepare Ge1-y C y alloys by implantation of C atoms into Ge crystals and post-annealing. For samples annealed at temperatures higher than 450°C, X-ray diffraction (XRD) spectra indicated that the Ge1-y C y alloys were successfully prepared. The highest substitutional C content was about 1 at.%. The optimum annealing temperature to incorporate C atoms into the substitutional sites was 450–500°C. We also investigated the dependence of the Raman intensity of the Ge–C local mode on the substitutional C content. The intensity of the Ge–C local mode was found to increase in proportion to the substitutional C content. Furthermore, the relationship between Ge–C peak intensity and substitutional C content was relatively in good agreement with that theoretically predicted.

ABSTRACT:Radical polymerizations of N-(tricyclo[3.3.1.1 3 · 7 ]decane-l-yl)4-vinylbenzylamine (AdO) and N-(tricyclo[3.3.1.13·7]decane-l-yl-methyl)4-vinylbenzylamine (Ad!) were conducted in bulk under nitrogen. The polymerizations of AdO and Ad I proceeded at the vinyl groups to give polymers with adamantane amino derivatives as pendant groups. The polymerization of AdO gave the polymers without any crosslinked product, although a partially or completely crosslinked polymer was obtained from the polymerization of Ad! at high temperature. Thermal stability of poly(AdO) and poly(Adl) was excellent, and the stability of poly( Ad I) was much higher than that of poly(AdO). The copolymerizations of AdO and Ad I with styrene and methyl methacrylate (MMA) were also performed by 2,2'-azobis(isobutyronitrile) (AIBN) at 80°C. The copolymers had similar feed ratios of monomers to styrene or MMA.

The nucleophilic addition of organotitanium reagents to α-keto amides derived from (2R,5R)-trans-2,5-bis(t-butyldimethylsiloxymethylsiloxymethyl)pyrrolidine [(R,R)-BTBSP] afforded the corresponding α-hydroxy amides with very high diastereofacial selectivity.