Fujiwara, Saiya, Masanori Hosoyamada, Kenichiro Tateishi, Tomohiro Uesaka, Keiko Ideta, Nobuo Kimizuka, and Nobuhiro Yanai. “Dynamic Nuclear Polarization of Metal–Organic Frameworks Using Photoexcited Triplet Electrons.” Journal of the American Chemical Society 140, no. 46 (November 21, 2018): 15606–10.
While dynamic nuclear polarization based on photoexcited triplet electrons (triplet-DNP) has the potential to hyperpolarize nuclear spins of target substrates in the low magnetic ﬁeld at room temperature, there has been no triplet-DNP system oﬀering structural rigidity and substrate accessibility. Here, we report the ﬁrst example of triplet-DNP of nanoporous metal−organic frameworks. Accommodation of a carboxylate-modiﬁed pentacene derivative in a partially deuterated ZIF-8 (DZIF-8) results in a clear 1H NMR signal enhancement over thermal equilibrium.