The reactions of 2,4-diaryl-6-tert-butylnitrosobenzenes with 2,2'-azobis[2-(methoxycarbonyl)propane] (5a), 2,2'-azobis(2-cyano-4-methylpentane) (5b), and 2,2'-azobis(2-cyano-4-methyl-4-methoxypentane) (5c) in refluxing benzene gave stable N-tert-alkoxy-2,4-diaryl-6-tert-butylphenylaminyls, which were successfully isolated as radical crystals in 13-52% yields after column chromatography. The radical yields depended on the reaction time and the molar ratio of azo compounds to nitroso compounds. In the same manner, acetyl- and cyano-group-carrying N-tert-alkoxyarylaminyls were generated by the reaction of 2-phenyl-4-(4-acetylphenyl)-6-tert-butylnitrosobenzene and 2-phenyl-4-(4-cyanophenyl)-6-tert-butylnitrosobenzene with 5a and 5b, and they were isolated as radical crystals. X-ray crystallographic analyses were performed for two radicals, and their molecular structures were discussed in detail. The magnetic properties were measured for the two isolated radicals with SQUID in the temperature range 1.8-300 K. One radical showed a weak ferromagnetic interaction (theta = 0.2 K) between the radicals, and the other showed a weak antiferromagnetic interaction (theta = -3.8 K). The ferromagnetic interaction was analyzed based on the X-ray crystallographic structure.

Radicals. -Stable title radicals (III) are synthesized by heating nitrosobenzene (I) and azo compounds (II) in refluxing benzene and isolated as radical crystals. Their structures are confirmed by the elemental analyses, EST and X-ray crystallography. -(MIURA*, Y.; MURANAKA, Y.; Chem. Lett. 34 (2005) 4, 480-481; Dep. Appl. Chem., Fac. Eng.,

Stable N-tert-alkoxy-2,4-diphenyl-6-tert-butylphenylaminyl radicals were prepared by heating 2,4-diphenyl-6-tert-butylphenylnitrosobenzenes and azo compounds in refluxing benzene and isolated as radical crystals. Their structures were confirmed by the elemental analyses, ESR, and X-ray crystallography.

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