A simple shape-persistent organic molecular container is capable of selective absorption and storage of I(2(g)) over water vapor and NO gas even in its amorphous solid state. In addition, the strongly associated I(2) can be efficiently released from the charged container in organic solvents under ambient conditions.

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The reaction of Ni(ClO4)2 with 4 equiv of pyrazole (pzH) in MeCN leads to [Ni(pzH)2(HNC(Me)pz)2](ClO4)2 via the intermediate [Ni(MeCN)2(pzH)4](ClO4)2, which is the first pyrazole−nitrile coupling reaction activated by a Ni(II) complex. The reaction is also successfully conducted with other nitriles RCN bearing an electron-donating group (R = Et, Bz) and is counteranion-specific. The reaction proceeds more quickly with NO3 − as counteranion than with ClO4 −, and BF4 − is found to be unsatisfactory for the coupling reaction. As for the X-ray crystal structures, [Ni(MeCN)2(pzH)4](ClO4)2 possesses stronger pyrazolyl NH···anion hydrogen-bonding interactions than does [Ni(MeCN)2(pzH)4](BF4)2. The same trend is also observed by solution IR (pyrazolyl NH) analysis. The supramolecular structure of the complex [Ni(pzH)2(HNC(Me)pz)2](ClO4)2 displays a two-dimensional network dominated by cooperative face-to-face π−π stacking and edge-to-face CH···π bonding interactions. In addition, a mechanism based on anion-mediated/hydrogen-bonding-driven proton transfer for the coupling reaction is proposed.

A simple organic molecular container can selectively encapsulate the volatile and highly reactive MeI through hydrogen-bonding interactions in solution. The remarkable encapsulation of MeI without self-methylation of the container appears to be determined by the complementary binding sites and the rigidity of the hydrogen-bonding array constrained by the molecular framework.

Nuclear resonance vibrational spectroscopy (NRVS) and density functional theory (DFT) are complementary tools for studying the vibrational and geometric structures of specific isotopically labeled molecular systems. Here we apply NRVS and DFT to characterize the trans-[57Fe­(η2-H2)­(H)­(dppe)2]­[BPh4] [dppe = 1,2-bis­(diphenylphosphino)­ethane] complex. Heretofore, most NRVS observations have centered on the spectral region below 1000 cm–1, where the 57Fe signal is strongest. In this work, we show that state-of-the-art synchrotron facilities can extend the observable region to 2000 cm–1 and likely beyond, in measurements that require less than 1 day. The 57Fe–H stretch was revealed at 1915 cm–1, along with the asymmetric 57Fe–H2 stretch at 1774 cm–1. For a small fraction of the H2-dissociated product, the 57Fe–H stretch was detected at 1956 cm–1. The unique sensitivity to 57Fe motion and the isolated nature of the Fe–H/H2 stretching modes enabled NRVS to quantitatively analyze the sample composition.