The nature of the bonding in some P–N, As–N, and S–N compounds

Abstract

The 15N-lH coupling constants in some amino-present some new W -H spin coupling data which are phosphines, aminoarsines, and sulphenamides have been relevant to these questions. determined.The appropriate =N-labelled compounds (Table ) were prepared by substituting 96-57' enriched 15NH3 for 14NH3 phine, (CH,),NPF,, has revealed a trigonal planar geometry about nitrogen and an unexpectedly short P-N bond distance. These findings have raised two important but related questions: (a) is trigonal planar nitrogen a general These results suggest that the nitrogen atoms are approxistructure feature of aminophosphines, aminoarsines, and mately trigonal planar in (CF,) ,PNH,, [CF,S] ,NH, and the sulphenamides? and (b) what is the importance of multiple phosphorane PF,(NH,),. On the other hand, the aminobonding in the N-X bonds of these compounds ? We arsines, the methyl-substituted aminophosphines, and 7 0 2s = I 0.43 J("N-H) -6

The alpha effect. A review

“…Cowley and Schweiger have hypothesized that electronegative substituents (like F or CF,) on P or S will shrink their 3d orbitals and allow for stronger p,-d, bonding in aminophosphines and sulfenamides [63]. Another barometer of bond strength is the torsional barrier.…”

Expedient Synthesis of a Metallostibine Os2(CO)8(µ‐SbPh): An Unusual and Strong Two‐Electron‐Donor Ligand

“…The mixture was stirred at room temperature for 12 h to give a yellow solution. The solvent was then pumped off, and the residue was separated by TLC with CH 2 Cl 2 /hexane (1:2) as the eluent to give one main yellow band of Os 2 W(CO) 13 (μ 3 -SbPh) (5) (R f = 0.50; yield = 18 mg, 86 %). 1 H NMR (C 6 D 6 ): δ = 7.26-7.28 (m, 2 H, Ph-H), 6.88-6.92 (m, 2 H, Ph-H), 6.81-6.85 (m, 1 H, Ph-H) ppm.…”

“…1 H NMR (C 6 D 6 ): δ = 7.26-7.28 (m, 2 H, Ph-H), 6.88-6.92 (m, 2 H, Ph-H), 6.81-6.85 (m, 1 H, Ph-H) ppm. 13 CCDC 1534534 (for 5) and 1534535 (for 2) contain the supplementary crystallographic data for this paper. These data can be obtained free of charge from The Cambridge Crystallographic Data Centre.…”

“…To the best of our knowledge, only one such metallostibine, namely, Fe 2 (CO) 8 {μ-Sb[CH(SiMe 3 ) 2 ]}, has been structurally characterized. [13] The bulky CH(SiMe 3 ) 2 substituent afforded steric protection of the lone pair of electrons on Sb, which thus allowed for its isolation. Herein, we report the generation and isolation, in high purity and yield, of a metallostibine of type B1 that is sterically less encumbered and has coordinating ability comparable to that of alkylphosphines.…”

Bis(diisopropylamino)phosphanyldiazomethane: A building block for the synthesis of stable carbene and nitrilimines

“…Several aspects of the structure merit discussion. The positive charge at phosphorus is delocalized onto the adjacent nitrogen atoms, as shown by their planar geometryo [22] and the short P-N bond lengths (1.61 vs. 1.68 A in H2PNH2) [23]. The structural parameters for the framework atoms (P1 and C l ) are as expected for a valence isoelectronic olefin: 1) the P-C distance of 1.62 A is short, evty compared to that in phosphaalkenes (1.64-1.69 A) [24], and in good agreement with that from a thForetical study on the parent compound (1.624 A) [21]; 2) the geoometry at both P1 and C1 is strictly planar ( -C 0.01 A).…”