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Abstract The “masked” terminal Zn sulfide, [K(2.2.2‐cryptand)][MeLZn(S)] (2) (MeL={(2,6‐iPr2C6H3)NC(Me)}2CH), was isolated via reaction of [MeLZnSCPh3] (1) with 2.3 equivalents of KC8in THF, in the presence of 2.2.2‐cryptand, at −78 °C. Complex2reacts readily with PhCCH and N2O to form [K(2.2.2‐cryptand)][MeLZn(SH)(CCPh)] (4) and [K(2.2.2‐cryptand)][MeLZn(SNNO)] (5), respectively, displaying both Brønsted and Lewis basicity. In addition, the electronic structure of2was examined computationally and compared with the previously reported Ni congener, [K(2.2.2‐cryptand)][tBuLNi(S)] (tBuL={(2,6‐iPr2C6H3)NC(tBu)}2CH).
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Reduction‐Induced C─C Cleavage and Site‐Specific Hydrogenation of a Highly Strained Bilayer Spironanographene
Abstract The chemical reduction of a bilayer spironanographene,spiro‐NG(C137H120), with Na and K metals in the presence of [2.2.2]cryptand to yield [Na+(2.2.2‐cryptand)](C137H121−) (1) and [K+(2.2.2‐cryptand)](C137H121−) (2), respectively, is reported. X‐ray crystallography reveals the formation of a new “naked” anion (spiro‐NGH−), in which spirocyclic ring cleavage and subsequent hydrogenation have occurred. Density Functional Theory (DFT) calculations suggest that the generation of the radical anion of the parent nanographene (spiro‐NG•−), upon electron acceptance from Na and K metals, induces the cleavage of the strained spirobifluorene core. The resulting spin density localizes on a particular carbon atom, previously attached to the spiranic sp3carbon atom, facilitating a site‐specific hydrogenation to afford (spiro‐NGH−). The electrostatic potential map of this anion reveals electron density concentrated at the five‐membered ring of the readily formed indenyl fragment, thus enhancing the aromaticity of the system. Furthermore, nuclear magnetic resonance (NMR) and UV–vis absorption spectroscopy experiments allowed to follow the in situ reduction and hydrogenation processes in detail.
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- Award ID(s):
- 2404031
- PAR ID:
- 10647627
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 64
- Issue:
- 33
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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