Publications by authors named "R C Clauss"

The syntheses of the first B9-connected carboranylphosphines (B9-Phos) featuring two carboranyl moieties as well as access to B9-Phos ligands with bulky electron-donating substituents, previously deemed unattainable, is reported. The electrochemical properties of the B9-Phos ligands were investigated, revealing the ability of the mesityl derivatives to form stabilized phosphoniumyl radical cations. The B9-Phos ligands display an extremely electron-releasing character surpassing that of alkyl phosphines and commonly used N-heterocyclic carbenes.

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The reaction of heteroditopic ligand 1 featuring a hard pyridine-hydrazone-pyrimidine (N,N,N) site and a softer pyrimidine-hydrazone-phosphane (N,N,P) pocket with [Pd(CHCN)](OTf) in different metal-to-ligand ratios (M : L) gave the homobimetallic Pd complex [Pd(1)(CHCN)](OTf) (2, M : L ratio 2 : 1), the [4 + 4] metallomacrocyclic Pd complex [Pd(1)](OTf) (3, M : L ratio 1 : 1) and the monometallic complex [Pd(1)](OTf) (4, M : L ratio 1 : 2). The soft N,N,P pocket preferably coordinates Pd, while the harder N,N,N coordination site selectively binds Zn forming the homoleptic meridional "corner" complexes [Zn(1)](OTf) (5) and [PdZn(1)](OTf) (6). The distinctive coordination behavior of ligand 1 is highlighted by the self-assembly of the heterometallic Pd/Zn grid-type complex [PdZn(1)](OTf) (7) in a one-pot reaction.

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A series of heterobimetallic Pd/M complexes (M = Mn, Co) were synthesised and tested as precatalysts for sequential Sonogashira coupling-alkyne semi-hydrogenation reactions to form -aryl alkenes. The carbometalated heterobimetallic Pd/Co complex CoPdL3' demonstrated an apparent cooperative effect compared to the corresponding monometallic counterparts. This compound was identified as a potent single-molecule catalyst for the one-pot Cu-free Sonogashira coupling of aryl bromides with terminal alkynes followed by chemo- and stereoselective semi-hydrogenation of the alkyne intermediate using NH·BH as a hydrogen source.

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A facile two-step synthesis of bis(1-methylhydrazinyl)pyrimidine from pyridine-2-carbaldehyde and 2-diphenylphosphanylbenzaldehyde gave access to the new asymmetric ligand . The phosphane selectively guides Pd into the softer tridentate ,, pocket, yielding monometallic complex . A second reaction with a 3d transition metal complex precursor (groups 7 to 12) fills the vacant ,, pocket and thus provides a variety of heterobimetallic complexes of the type Pd/M (M = Mn (), Fe (), Co (), Ni (), Cu (), Zn ()).

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In the past two decades, many studies have shown the paradoxical efficacy of zolpidem, a hypnotic used to induce sleep, in transiently alleviating various disorders of consciousness such as traumatic brain injury (TBI), dystonia, and Parkinson's disease. The mechanism of action of this effect of zolpidem is of great research interest. In this case study, we use magnetoencephalography (MEG) to investigate a fully conscious, ex-coma patient who suffered from neurological difficulties for a few years due to traumatic brain injury.

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