The complexes TpW(NO)(PMe 3 )(L), where L = phenol, N,N-dimethylanilinium, or naphthalene, undergo protonation followed by addition of an aromatic nucleophile. The addition of aromatic molecules occurs at the para carbon of the phenol or aniline ring or the beta carbon of the naphthalene. The addition occurs anti to the metal fragment, as determined by X-ray crystallography. In the case where L = phenol or N,N-dimethylanilinium, treatment of the bound arene with an electrophilic heteroatom followed by an aromatic nucleophile sets two stereocenters, with both additions occurring anti to the metal. The resultant ligands have been removed from the metal by oxidative decomplexation using ceric ammonium nitrate.

The complexes TpW(NO)(PMe3)(L), where L = 2H-phenol, 2H-p-cresol, 2H-5,6,7,8-tetrahydro-2-naphthol, 2H- N,N-dimethylanilinium were cyclopropanated using Simmons–Smith conditions. Cyclopropanated derivatives of 2H-N,N-dimethylanilinium were selectively ring-opened with HOTf/MeCN to form allylic species, which could be coupled with various nucleophiles. The nucleophilic addition occurs anti to the metal fragment, as determined by X-ray crystallography. Moreover, the cyclopropane ring opening occurs regioselectively, owing to the stabilization of the allylic cation by the metal fragment. The resulting ligands can, in some cases, be removed from the metal by oxidative decomplexation using ceric ammonium nitrate (CAN).

Radial head and neck fractures are one of the most common elbow fractures, comprising 2% to 5% of all fractures, and 30% of elbow fractures. Although uncomplicated Mason type I fractures can be managed nonsurgically, Mason type II-IV fractures require additional intervention. Mason type II-III fractures with 3 or fewer fragments are typically treated with open reduction and internal fixation using 2 to 3 lag screws. Transverse radial neck involvement or axial instability with screw-only fixation has historically required the additional use of a mini fragment T-plate or locking proximal radius plate. More recently, less invasive techniques such as the cross-screw and tripod techniques have been proposed. The purpose of this paper is to detail and demonstrate the proper implementation of the tripod technique using headless compression screws.

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2-(Dimethylamino)pyridine (2-DMAP) and 2-(dimethylamino)pyrimidine derivatives form η2-bound complexes with the dearomatization agent {TpW(NO)(PMe3)} that are each capable of undergoing a double protonation. In the case of 2-DMAP, the resulting π-allyl species reacts with the α-carbon of thiophene or 2-methylfuran, thereby coupling the heterocyclic rings. In the case of the thiophene-derived product, subsequent oxidative decomplexation using ceric ammonium nitrate affords a novel organic amidine derivative. Examples of tungsten-promoted acetylation and fluorination of the aminopyridine ring are also described.