<sup>
<i>n</i>
</sup>Bu<sub>4</sub>NI-catalyzed direct amination of benzoxazoles with tertiary amines using TBHP as oxidant under microwave irradiation
Abstract A facile, efficient, and practical method for nBu4NI-catalyzed direct C–H amination of benzoxazoles with tertiary amines has been developed. The system could be performed in the absence of metal catalyst and only requires tert-butyl hydroperoxide as oxidant under microwave irradiation. A variety of substituted benzoxazol-2-amines were synthesized with moderate to good yield.
In this article, a facile, efficient and practical method for Ni-catalyzed directC–H amination of benzoxazole with secondary amines has been developed. This procedure requires Ni(OAc)2·4H2O as catalyst, TBHP as oxidant and acid as the additive. A variety of substituted benzoxazol-2-amines were synthesized in moderate to good yields.
A facile, efficient, and practical method for copper-catalyzeddirectC–H amination of benzoxazoles with formamides or secondary amines has been developed. The system can be performed in the absence of external base and only requires O2 or even air as oxidant. A variety of substituted benzoxazol-2-amines were synthesized with moderate to excellent yield.
Zwitterionic Ring-Opened Oxyphosphonium Species from the Ph<sub>3</sub>P–I<sub>2</sub> Mediated Reactions of Benzo[<i>d</i>]oxazol-2(3<i>H</i>)-ones with Secondary Amines
Ph3P-I2-mediated reactions of benzo[d]oxazol-2(3H)-ones with acyclic secondary amines. The structure of one of these compounds was unambiguously confirmed by single-crystal X-ray analysis. Thermolysis of the betaines gave rise to 2-dialkylaminobenzoxazoles with concomitant loss of triphenylphosphine oxide, suggesting their possible role as intermediates in an alternative reaction path.