4-Phenoxyphenol: A Porous Molecular Material

4-Phenoxyphenol is a simple organic molecule that crystallizes as a porous material with channels running throughout the structure. The channels are constructed by a 6-fold hydrogen bonded ring and can host solvent molecules incorporated during crystal growth, with a minimum channel diameter of 5.8-5.9 angstrom; each channel usually contains a single solvent molecule per unit cell. The hydrogen bonded ring shows surprising flexibility, being able both to breathe and to sustain its crystalline integrity even when grown with empty pores. This is particularly surprising given that the remainder of the interactions within the crystal structure are C-H center dot center dot center dot pi interactions and are weak in nature. It is also possible to grow "dry" porous 4-phenoxyphenol crystals by using a bulky solvent in the recrystallization. © 2012, American Chemical Society

Reduction of a chelating bis(NHC) palladium(II) complex to [{μbis( NHC)}2Pd2H]+: a terminal hydride in a binuclear palladium(I) species formed under catalytically relevant conditions.

The first palladium(I) N-heterocyclic carbene complex has been isolated in high yield by the base-assisted reduction of a palladium(II) precursor. The location of the unique terminal hydride (see picture; PdI cyan, H white, N blue) was established by neutron crystal structure determination, and the solution fluxional behavior of the complex was explored. © 2010, Wiley-VCH Verlag Berli