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The silylated aryloxo ligands bis(o-silyloxyphenyl)phenylphosphine (abbreviated PhP{OT}2) and tris(o-trimethylsilyloxyphenyl)phosphine (abbreviated P{OT}3, where T = Me3Si) were prepared. Complexat...

The reaction of 1,5-Ph 4 P 2 N 4 Se 2 with Pt(PPh 3 ) 2 (CH 2 =CH 2 ) or Pd(PPh 3 ) 4 in toluene at 0 o C produces the η 2 -Se,Se'-bonded complexes M(PPh 3 ) 2 (1,5-Ph 4 P 2 N 4 Se 2 ) (2a, M=Pt; 2b, M=Pd) characterized by their 31 P and 77 Se NMR spectra. Simulation of the 77 Se NMR spectra gave detailed coupling information for 2a and 2b.

The first example of a tetrahalogenated derivative of a diphosphadithiatetrazocine, 1,5-Cl(2)P(NSN)(2)PCl(2) (3), was synthesized by cyclocondensation of a 2:1 mixture of SCl(2) and SO(2)Cl(2) with Cl(2)P(NSiMe(3))N(SiMe(3))(2) in CH(2)Cl(2). The heterocycle 3 was isolated as an orange, moisture-sensitive, thermally labile solid and characterized by mass spectrometry, (31)P NMR, and UV-visible spectroscopy. The low-field (31)P NMR chemical shift (93.7 ppm) is indicative of a cross-ring S-S interaction in the eight-membered P(2)N(4)S(2) ring, and this conclusion is supported by density-functional computations. Compound 3 exhibits unusual physical properties compared with those of the known tetraalkyl or aryl derivatives; mild heating (90 degrees C) produces an orange rubbery material. The bishomoaromatic character of the diphosphadithiatetrazocine 1,5-R(2)P(NSN)(2)PR(2) (R = Me, Cl, F) is evinced by the negative nucleus-independent chemical shift (NICS) values, and the through-space bishomoconjugation in the eight-membered ring decreases with increasing electronegativity of the substituents attached to the P atoms.

The reaction of the diphosphadithiatetrazocines 1,5-R 4 P 2 N 4 S 2 with [MCl 2 (PEt 3 )] 2 (M=Pt, Pd) in a 2:1 molar ratio in CH 2 Cl 2 or THF at 23 o C produces the 1:1 adducts trans-[MCl 2 (PEt 3 )(R 4 P 2 N 4 S 2 )] (M=Pt, R=Ph; M=Pt, R=Et; M=Pt, R=Me; M=Pd, R=Et; M=Pd, R=Me) in which the P 2 N 4 S 2 ligand is bound to either palladium or platinum via nitrogen.

Reactions of the bis(phosphine chalcogenides) CH 2 {P(X)R 2 }{P(Y)R' 2 } (X, Y=O, S, Se) and their derived anions [CH{P-(X)R 2 }{P(Y)R' 2 }] - with chloroplatinum complexes PtCl 4 2- , [Pt 2 Cl 4 (PEt 3 ) 2 ], or (Pt 2 Cl 2 (PEt 3 ) 4 ] 2+ result in a wide coordination complexes.

Replacement of the bridging acetate groups in [Ru 2 (CO) 4 (μ-O 2 CMe) 2 (PR' 2 R″) 2 ] (R',R″=Ph, Me) by the dithiophosphinate anions R 2 PS 2 − (R=Me, Ph) yields a new class of dithiophosphinate-bridged Ru(I) complexes, [Ru 2 (CO) 4 (μ-S 2 PR 2 ) 2 (PR' 2 R″) 2 ]. Although the Ru-Ru bond in these species can be reversibly protonated, it does not react with [Au(PPh 3 )][BF 4 ], diazomethane, or dimethyl acetylenedicarboxylate. Reation of the related acetate-bridged species [Ru 2 (CO) 4 (μ-O 2 CMe) 2 (NCMe) 2 ] with NaS 2 PMe 2 does not yield the expected dithiophosphinate-bridged product but instead gives the mononuclear species [Ru-(CO) 2 (η 2 -S 2 PMe 2 ) 2 ] along with Na 2 S, NaO 2 CMe, MeCN, and Me 2 P(S)P(S)Me 2

The silylated aryloxo ligands bis(o-silyloxyphenyl)phenylphosphine (abbreviated PhP{OT}(2)) and tris(o-trimethylsilyloxyphenyl)phosphine (abbreviated P{OT}(3), where T = Me(3)Si) were prepared. Complexation reactions with O=ReCl(2)(OEt)(PPh(3))(2) and O=ReCl(3)(PPh(3))(2) proceed by displacement of one PPh(3) and the subsequent stepwise replacement of the OEt and/or Cl substituents. The new complex Re(O)Cl(2)[kappa(2)-(P,O)-(PhP{O}{OT})](PPh(3)), formed by elimination of Me(3)SiOEt, exists in diastereomeric cis and trans forms. Elimination of a second equivalent of Me(3)SiCl gives Re(O)Cl[kappa(3)-(P,O,O)-(PhP{O}(2))](PPh(3)). Similarly P{OT}(3) converts Re(O)Cl(2)(OEt)(PPh(3))(2) to ReOCl(2)[kappa(2)-(P,O)-(P{O}{OT}(2))](PPh(3)) (5) (structurally characterized as 5.0.875CH(2)Cl(2)): crystal data; triclinic Ponemacr;, a = 14.302(4) Å, b = 18.734(2) Å, c = 17.639(4) Å, alpha = 80.950(12) degrees, beta = 80.12(2) degrees, gamma = 81.76(2) degrees, Z = 4. Final R(1) and wR(2) values are 0.0852 and 0.1525, respectively on F(o)(2)2sigma(F(o)(2)) data (or 0.1948 and 0.2019 on all data). The phenoxy phosphine ligand in 5 is bound via P and one O to Re. The P atoms are mutually cis to each other and to the terminal oxygen on Re. Two ortho-trimethylsiloxy substituted phenyl rings dangle from the coordinated phosphorus atom. Complex 5 can be converted to Re(O)Cl[kappa(3)-(P,O,O)-(P{O}(2){OT})](PPh(3)) (6) by treatment with PPN(+) Cl(-) and 6 was also obtained by direct reaction of Re(O)Cl(3)(PPh(3))(2) with P{OT}(3) at higher temperatures. The complex 6 has been structurally characterized: crystal data triclinic, Ponemacr;, a = 10.1509(6) Å, b = 12.1123(8) Å, c = 16.2142(14) Å, alpha = 97.851(7) degrees, beta = 94.852(7) degrees, gamma = 96.889(6) degrees, Z = 2. Final R(1) and wR(2) values were 0.0303 and 0.0721 on F(o)(2)2sigma(F(o)(2)) data (or 0.0348 and 0.0742 on all data). The phenoxyphosphine ligand in 6 is bound facially to Re through P and two of the phenoxy oxygens. The Ph(3)P group and terminal oxygen atoms are cis to the oxygen atoms of the phenoxy ligands and the Cl lies trans to P. One trimethylsiloxyphenol group dangles. Careful hydrolysis of 6 gave Re(O)Cl[kappa(3)-(P,O,O)-(P{O}(2){OH})](PPh(3)) which was also formed during complexation reactions in moist solvent. Solution (31)P{(1)H} NMR demonstrated cis- or trans-(P,P) geometry for the complexes, which was confirmed in the two aforementioned cases by structure determinations.