The synthesis of four new bulky bidentate phosphines that possess both tert-butyl and trifluoromethylphenyl substituents is described. Symmetric ligands were readily obtained by alkylation of phosphidoboranes of the type Li[P(BH(3))(tBu)(Ar)] with dihaloalkanes. Non-symmetric ligands were prepared from a new stable precursor, tBu(2)P(BH(3))(CH(2))(3)Br, that should prove useful for other ligand syntheses. Palladium(II) complexes of the four new ligands were prepared and were characterised by spectroscopic methods, microanalysis and X-ray crystallography. The new [PdCl(2)(L)] complexes were evaluated as catalysts for the hydroxycarbonylation of styrene and found to give unprecedented regioselectivity and yields for a diphosphine-based catalyst. A study on promoter effects reveals that the presence of acid and chloride is necessary to achieve such selectivities. It has been proposed in the literature that such conditions result in a new pathway in which styrene is converted into 2-phenethyl chloride, with the latter being the real substrate in the reaction. However, a deuterium labelling study seems to rule out this mechanism, at least under the conditions used herein.

The use of palladium catalysts derived from 1,1 -bis-diisopropylphosphino-ferrocene and a microwave heating source allows the coupling of a range of ortho-substituted aryl bromides to diphenylphosphine derivatives to proceed in good yield in under 30 min. Optimization studies reveal that the combination of diphenylphosphine and DABCO is superior to more basic phosphide nucleophiles such as Ph 2 PK or Ph 2 PMgBr. High yields are only observed when moderately bulky electron rich diphosphines are used as ligands. The differences between P-C coupling and other cross-coupling reactions are discussed in the light of the reactivity observed. Studies aimed at producing industrially important 1,2-bis-phosphino-benzene ligands are also described.

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Organo-phosphorus compounds S 0080Palladium-Catalyzed P-C Bond Forming Reactions Between Diphenylphosphine and ortho-Substituted Aryl Bromides. -A catalyst system for the coupling of diphenylphosphine derivatives with ortho-substituted aryl halides is developed. The attempt to prepare the well-known ligand PhanePhos (XII) affords the compound in a low yield. -(DAMIAN, K.; CLARKE*, M. L.; COBLEY, C. J.; Appl. Organomet. Chem. 23 (2009) 7, 272-276; Sch. Chem., Univ. St. Andrews, St. Andrews, Fife KY16 9ST, UK; Eng.) -Bartels 43-183

Glomangiopericytoma is a rare neoplasm of the nasal and paranasal sinuses comprising less than 1% of all tumors of the said region. We report of a 59-year-old hypertensive male who presented with epistaxis. CT scan findings showed a mass in the right nasal cavity with extension into the ethmoid and sphenoid sinuses. Histopathologic diagnosis was glomangiopericytoma confirmed with immunohistochemistry studies. Prognosis is favorable with complete resection of tumor and long-term monitoring.

High-grade B-cell lymphoma with MYC and BCL2 and-or BCL6 rearrangements, also called doublehit lymphoma, is an aggressive mature B-cell lymphoma that carries both MYC and BCL2 and/or BCL6 translocations. This can present as a diagnostic challenge since clinical characteristics, morphology and immunophenotype are not accurate indicators of underlying genetic aberrations in this type of lymphoma. We report a case of a 25-year-old male who presented with a one-year history of cough, gradually increasing abdominal girth and jaundice. Definitive diagnosis was made post-mortem with additional ancillary studies using immunohistochemistry staining and fluorescent in-situ hybridization studies.