| Abstract
| - The synthesis and X-ray structures are reported for [(η6-hydroquinone)Rh(P(OPh)3)2]+X- (X = BF4,ClO4, SbF6, OTf, OTs, OPf), [(η6-resorcinol)Rh(P(OPh)3)2]+BF4-, and [(η6-4,4‘-biphenol)Rh(P(OPh)3)2]+BF4-.In these complexes, the −OH groups are activated by the electrophilic rhodium moiety to participate incharge-assisted hydrogen bonding to the anionic counterion. The crystal structures feature three kinds ofnoncovalent interactionshydrogen bonding, Coulombic attraction, and π−π stacking, which result inan intriguing array of architectures: dimeric, 1-D chain, C2 helical, and C3 helical. The nature of thecharge-assisted hydrogen bonding and the resulting 3-D structure in these systems are remarkably dependenton the identity of the anion. Robust porous networks are formed rapidly (minutes or less) with [(η6-hydroquinone)Rh(P(OPh)3)2]+X- (X = BF4, ClO4) and [(η6-resorcinol)Rh(P(OPh)3)2]+BF4-. Thehydrophobic pores in [(η6-hydroquinone)Rh(P(OPh)3)2]+ClO4- bind toluene reversibly. This workdemonstrates that self-assembly of well-designed organometallic building blocks via charge-assistedhydrogen bonding is an effective strategy for the construction of robust porous networks. With counterionscontaining both oxygen and fluorine, it was found that the former is invariably the hydrogen bond acceptor,a result in agreement with atomic charge calculations. It is anticipated that self-assembly via charge-assisted hydrogen bonding is an approach applicable in many organometallic systems.
- The solid-state structures of [(η6-hydroquinone)Rh(P(OPh)3)2]+X- (X = BF4, ClO4, SbF6, OTf, OTs, OPf) feature charge-assisted hydrogen bonding, Coulombic, and π−π-stacking interactions, which result in an intriguing array of architectures. Robust networks containing hydrophobic pores, as illustrated, are formed when the counterion is BF4- or ClO4-.
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