Sagami Chemical Research Center

In the course of an agrochem. random screening test of 1-alkylpyrazole-4-carboxamide analogs showing herbicidal activity, it was discovered that some 1-alkyl-3-sulfonyloxypyrazole-4-carboxamides exhibited high insecticidal activity.These derivatives were readily synthesized through the reaction of various amines with mixed anhydrides of pyrazole-4-carboxylic acids.All pyrazole-4-carboxamides synthesized were evaluated for insecticidal activity and their structure-activity relations are discussed.

The spiro-type polymer having alternate structure of cyclic silphenylenesiloxane and cyclic carbosilane moieties was synthesized by the hydrosilylation polymerization of cyclic silphenylenesiloxane derivative having two allylhydrosilyl groups.The thermal properties of the obtained polymers were investigated by using the thermogravimetric anal. and the differential scanning calorimetry.The obtained spiro-type polymer, P3, exhibited the relatively high glass transition temperature of 77°C and the weight residue at 1000°C of 73 %.In addition, P3 annealed at 200°C was an excellent heat-resistant material insoluble to common solvents.The dielec. constants, ε, of polymer films of P3 and the annealed sample were evaluated by the measurement of refractive indexes estimated from the ellipsometry method.Both samples showed relatively low ε.

Novel Ta and Nb compounds Ta(NtBu)(OtBu)3 (1) and Nb(NtBu)(OtBu)3 (2) were prepared as volatile liquid precursors for the MOCVD process. Ta2O5 and Nb2O5 films were obtained by using 1 and 2 in a lower temperature regime than pentaethoxy tantalum (PET) and pentaethoxy niobium (PEN). The deposition rates of 1 and 2 were higher more than 10 times than PET and PEN. Both precursors 1 and 2 gave conformal metal-oxide films, which exhibit excellent step coverage of over 90% on SiO2 holes with an aspect ratio of ca. 6.