부산대학교 도서관

Abstract: Reducible 3,6‐bis(3,5‐dimethyl‐pyrazolyl)1,2,4,5‐tetrazine was employed to isolate supramolecular air‐stable [Co4] and [Zn4] squares, which were achieved via careful selection of counterions rather than the use of reducing agents. Magnetic susceptibility studies revealed a strong radical‐CoII exchange coupling (Jrad‐Co/hc=−118 cm−1, −2J formalism) with a spin ground state of ST=4, whereas the unreduced analogue revealed negligible coupling between the Co centers (JCo‐Co/hc=−0.64 cm−1). Radical–radical coupling was also probed in the [Zn4] congener, which led to Jrad‐rad/hc=−15.9(5) cm−1. These results highlight the versatile air‐stable coordination chemistry of tetrazine and the importance of exploiting easily reducible delocalized radical to promote strong exchange coupling between spin carriers. [ABSTRACT FROM AUTHOR]