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Readily-available triarylphosphines are explored as organocatalysts for the hydroarsination reaction. When compared to transition metal catalysis, phosphine organocatalysis greatly improved solvent compatibility of the hydroarsination of nitrostyrenes. Upon complete conversion, arsine products were isolated in up to 99% yield while up to 48% of the phosphine catalyst was still active. A mechanism was proposed and structure-activity analysis regarding catalyst activity concluded that sterically-bulkier catalysts were effective at minimizing catalyst deactivation. Image 1 • Air-stable triarylphosphine catalysts for the hydroarsination reaction. • Catalysis compatible with non-alcoholic solvents. • Arsine-mediated phosphine oxidation observed. • Organophosphine catalysis mechanistically different from transition metal catalysis. [ABSTRACT FROM AUTHOR]

Abstract The ruthenacyclic carbamoyl complexes [Ru (2-NHC(O)C 5 H 4 N) (CO) 2 (X) (NCMe)] (X = Cl, Br) (1) and [Ru (2-NHC(O)C 5 H 4 N) (CO) 2 (2-S-Py)] (2) undergo substitution reactions with organophosphines to afford derivatives which are prone to a redistribution of the phosphine ligand. We have studied these redistribution reactions experimentally and computationally, and proposed an essentially common reaction pathway. The results suggest that the carbamoyl ligand exerts a very strong trans effect. Graphical abstract Image 1 Highlights • Phosphine derivatives of ruthenacyclic carbamoyls prone to redistribution of the phosphine ligand. • Weakening of Ru-P bond due to very strong trans effect of carbamoyl ligand. • Proposed pathway involves a 16-electron intermediate. [ABSTRACT FROM AUTHOR]

• Reactions of osmostibine precursor Os 2 (CO) 8 (µ 3 -SbPh)Os(CO) 3 (Cl) 2 (1) under TMNO activation. • Mono-, di-, tri- and tetra-substituted derivatives with PPh 3 and CH 3 CN isolated. • First substitution occurs at the Os(CO) 3 Cl 2 "spike"; shuts down release of osmostibine. • CH 3 CN-substituted osmostibine generated in situ by reaction of bis-acetonitrile derivative of 1 with CO and trapped with W(CO) 5 (NCCH 3). Derivatisation of the osmium carbonyl cluster Os 2 (CO) 8 (µ 3 -SbPh)Os(CO) 3 (Cl) 2 , 1 , the precursor to the metalloligand Os 2 (CO) 8 (µ -SbPh), 2 , was explored as a route to derivatives of the latter. The reaction of 1 with PPh 3 in different stoichiometries and under trimethylamine N-oxide activation in CH 3 CN led to mono-, di-, tri- and tetra-substitution by PPh 3 and CH 3 CN. The first substitution occurred at the Os(CO) 3 Cl 2 "spike" and although subsequent substitution favoured CH 3 CN at the osmostibine moiety, the latter was not readily displaced by PPh 3. Substitution at the "spike" also shut down release of the substituted osmostibine. The CH 3 CN-substituted osmostibine could, however, be generated in situ through the bis-acetonitrile derivative of 1 by conversion of the Os(CO) 2 (NCCH 3)Cl 2 "spike" back into its removable Os(CO) 3 Cl 2 form through reaction with CO gas, and was then trapped with W(CO) 5 (NCCH 3). [ABSTRACT FROM AUTHOR]

The first example of an enantioselective hydrophosphination reaction of ethenesulfonyl fluoride derivatives catalyzed by a phosphapalladacycle afforded chiral sulfonyl fluoride-derived phosphines in quantitative yields and enantioselectivities of up to 93% ee. Investigations revealed the importance of adjacent vacant sites within the active metal center for intramolecular nucleophilic attack to provide the functionalized phosphine. Image 1 • Asymmetric hydrophosphination reaction accessing phosphinosulfonyl fluorides. • Excellent yields and enantioselectivities for most substrates. • Ability to generate free phosphines from the catalytic protocol. • Importance of adjacent vacant sites within the active center of the catalyst. [ABSTRACT FROM AUTHOR]