| Abstract
| - Reaction ofN,N‘-bis(tolylsulfonyl)-1,2-diaminoethanewith PhPCl2 gives in 62% yield the phosphonousdiamide2-phenyl-1,3-bis(p-tolylsulfonyl)-1,3,2-diazaphospholidine(4, “TosL”) and with Ph2PCl in 43%yield thediphosphinous amideN,N‘-bis(diphenylphosphino)-N,N‘-bis(p-tolylsulfonyl)-1,2-ethanediamine(5, “diTosL”).Reaction of 4 with (THF)W(CO)5 gives(TosL)W(CO)5 (6) in 77% yield, andreaction of 5 withtrans-BrW(CO)4NOgives cis, cis,trans-(diTosL)W(CO)2(NO)Br(8) in 86% yield. The IR, 13C NMR, and31P NMR spectra of 4, 5,6, and 8 are compared to those of a variety ofcompounds including LW(CO)5 (L = PMe3,PPh3, PPh(NEt2)2,P(OMe)3, P(CF3)3),L2W(CO)2(NO)Br (L2 =Ar2PCH2CH2PAr2(Ar = Ph (diphos), C6F5(diphos-F20)),(CH3CN)2),and the free ligands as appropriate. The IR data are interpretedto suggest a relative ordering of ligand acceptorability of P(CF3)3> 4 ≈P(OMe)3> PPh3 ≈PPh(NEt2)2 and a relative ordering ofligand donor ability ofPPh(NEt2)2 ≥ P(OMe)3>PPh3> 4> P(CF3)3.The chelating ligand diTosL is about aselectron-withdrawingas diphos-F20, on the basis of the IR data. The31P NMR data qualitatively support the conclusion that TosLanddiTosL are highly electron-withdrawing ligands, on the basis of1JPW. The 13C datado not permit any suchgeneralizations, although the spectra of the diphosphine ligands andadducts are of interest due to the observationof “virtual coupling” that surprisingly can be simulated only asABX rather than AA‘X spin-systems.
- The synthesesof a novel type of electron-withdrawing phosphine ligand, monodentate“TosL” and chelating “diTosL”, are described. Tungstencomplexes are prepared and electronic properties assessed by IR andNMR. TosL ranks just below P(CF3)3, anddiTosL about the same as(C6F5)2PCH2CH2P(C6F5)2in electron-withdrawingability.
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