| Budget Amount *help |
¥1,800,000 (Direct Cost: ¥1,800,000)
Fiscal Year 1986: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1985: ¥1,300,000 (Direct Cost: ¥1,300,000)
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| Research Abstract |
Several pyridinium and triphenylphosphonium ylides bearing arylazo group have been prepared from the addition reaction of arenediazonium ions to the ylides derived from pyridinium and phosphonium salts. The reaction was found to be accelerated under phase transfer catalyzed conditions in water-dichloroethane system in the presence of catalyst such as tetraalkylammonium halides and sodium perchlorate. On the contrary, the reaction with sulfonium ylides,e.g., dimethylsulfonium benzoylmethylide, afforded 1,2-diaryl-azoethylene, arising from the decomposition of the initial addition product.
It has been found that arylazo substituted pyridinium ylides are moderately stable and act as a precursor of arylazocarbene intermediate (Ar-N=N-C-R, R: COPh, CN). Thus, in the presence of alkene, it decomposed thermally in boiling chloroform to yield arylazo substituted cyclopropanes. Similarly, the reaction with Schiff base yielded arylazo aziridines. The aryazocarbene could also be trapped by such nucleophiles as triphenyl-phosphine and morpholine giving newer class arylazo substituted ylides.
On the other hand, arylazo phosphonium ylide reacted with aldehydes resulting in the formation of arylazoalkene, although their yields were low, owing to the poor nucleophilicity of arylazo phosphonium ylide.
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