3092 Organometallics, Vol. 19, No. 16, 2000
Ara et al.
6.7 (m, C6H4, C∧P), 5.42 (s, C3-H, acac), 3.84 (νA), 3.76 (νB)
(2J H-H ) 13.12 Hz, CH2, C∧P), 2.78 (s, CH3, C∧P), 2.43 (s, CH3,
C∧P), 1.94 (s CH3, acac), 1.80 (s CH3, acac). 13C {1H}: 186.04
(s, CO, acac), 183.63 (s, CO, acac), 101.74 (s, 3J Pt-C ) 54.6 Hz,
cleavage. However, the reactions of the analogous
palladium complexes with HgX2 (X ) Br, CH3COO,
CF3COO) proceed with transmetalation, giving rise to
binuclear compounds with the C∧P acting as an un-
precedented bridging ligand between the palladium and
mercury atoms. Such transmetalation reactions were
thought to proceed through electrophilic attack of the
mercury salt on the Pd-C(sp3) bond rather than on the
palladium center.5
â-Diketonate complexes usually contain the â-di-
ketonate bonded via the two oxygen atoms forming a
six-membered planar ring.6 It has been shown that the
central carbon atom on the â-diketonate ring has
nucleophilic character and undergoes metal-carbon
bond formation under appropriate conditions.7
Taking into account the proven ability of the Hg to
form Pt-Hg and C-Hg bonds,4,5 we extended our work
to the synthesis of new neutral complexes of Pd(II) and
Pt(II) containing the same C∧P group and acetyl-
acetonate as auxiliary ligand. These complexes contain
different nucleophilic centers (Pt or Pd, O, C) capable
of reacting with mercury salts acting as electrophilic
reagents. The synthesis of [M(C∧P)(acac)] (M ) Pt, Pd)
and a study of their reactivity toward HgX2 (X ) Br, I,
CH3COO, CF3COO) form the subject of this work. As a
result, we report here the synthesis and the structural
characterization of new mixed Pt-Hg heteropolynuclear
complexes.
4
C3, acac), 28.36 (s, CH3, acac), 27.71 (d, J P-C ) 6.9 Hz, CH3,
acac), 23.31 (s, CH3, C∧P), 22.32 (s, CH3, C∧P), 14.22 (s, J Pt-C
) 747.3 Hz, CH2, C∧P).
[{P t{CH2-C6H4-P (o-tolyl)2-KC,P }(acac-O,O′)HgBr (µ-Br )}2-
(µ-HgBr 2)] (3). Compound 3 was prepared in the same way
as compound 2. 1 (0.2202 g, 0.369 mmol) in Et2O/CH2Cl2 (60/7
mL), HgBr2 (0.1328 g, 0.369 mmol), 15 min. Yield ) 0.2160 g,
51.4%. Anal. Calcd for C52H54Hg3Br6O4P2Pt2: C, 27.44; H, 2.39.
Found: C, 27.28; H, 2.28. IR: 1568 (vs), 1515 (s), 1265 (m),
785 (s), 760 (m), 748 (m), 691 (m), 609 (m), 591 (m), 564 (m),
530 (s), 519 (m), 508 (m), 491 (m), 475 (m), 460 (m). 31P{1H}
NMR (CDCl3, 293 K): 9.43 (s, J Pt-P ) 4244.8 Hz). 1H NMR:
2
7.6-6.8 (m, C6H4, C∧P), 5.49 (s, C3-H, acac), 4.06 (s, J Pt-H
)
2
116.1 Hz, 1H, CH2, C∧P), 4.06 (s, J Pt-H ) 77.4 Hz, 1H, CH2,
C∧P), 2.76 (s, CH3, C∧P), 2.44 (s, CH3, C∧P), 1.97 (s, CH3,
acac), 1.86 (s, CH3, acac). 13C {1H}: 187.27 (s, CO, acac), 184.01
(s, CO, acac), 102.59 (s, J Pt-C ) 55.7 Hz, C3, acac), 28.41 (s,
3
CH3, acac), 27.87 (d, 4J P-C ) 6.6 Hz, CH3, acac), 24.29 (d, 3J P-C
3
) 8.3 Hz, CH3, C∧P), 22.75 (d, J P-C ) 5.1 Hz, CH3, C∧P),
17.14 (s, CH2, C∧P).
[P t{CH2-C6H4-P (o-tolyl)2-KC,P }(µ-O2CCH3)2Hg(µ3-acac2-
-
KC3,O)Hg(O2CCH3-KO)]2 (4). To a suspension of [Pt{CH2-
C6H4-P(o-tolyl)2-κC,P}(acac-O,O′)] (1) (0.1865 g, 0.312 mmol)
in CH3OH (20 mL) at 0 °C was added Hg(O2CCH3)2 (0.1988 g,
0.624 mmol). The mixture was stirred for 10 min, and the
filtered solution was evaporated to dryness. The residue was
treated with 20 mL of CHCl3, and the suspended solid was
removed by filtration. The solution was then evaporated to
dryness, and n-pentane (30 mL) was added to the residue. A
yellow solid remained and was filtered off, 4 (0.0856 g, 23.3%).
Anal. Calcd for C64H70Hg4O16P2Pt2: C, 32.71; H, 3.00. Found:
C, 33.12; H, 2.92. IR: 1652 (w), 1582 (m), 751 (s), 675 (m),
616 (w), 605 (w), 591 (s), 565 (s), 531 (s), 508 (w), 488 (m), 478
Exp er im en ta l Section
Gen er a l P r oced u r es. Elemental analyses were performed
on a Perkin-Elmer 240-B microanalyzer. IR spectra were
recorded on a Perkin-Elmer 599 spectrophotometer (Nujol
mulls between polyethylene plates in the range 200-4000
cm-1). NMR spectra were recorded on either a Varian XL-200
or a Varian Unity 300 NMR spectrometer using the standard
references. [Pd{CH2-C6H4-P(o-tolyl)2-κC,P}(acac-O,O′)] was pre-
pared as described elsewhere.8
(s), 461 (m). 31P{1H} NMR (CDCl3, 293 K): 11.78 (s, J Pt-P
)
3779.9 Hz, J Hg-P ) 111.8 Hz).1H NMR: 7.7-6.8 (m, C6H4,
C∧P), 4.14 (νA), 4.05 (νB) (2J H-H ) 16.8 Hz, CH2, C∧P), 3.05
(s, CH3, C∧P), 2.02 (s, CH3, C∧P, bridging acetate), 1.98 (s,
CH3, bridging acetate), 1.95 (s, CH3, acac), 1.90 (s CH3, ter-
minal acetate). 13C{1H} NMR (CD2Cl2, 293 K): 204.37 (s, CO,
acac), 202.92 (s, CO, acac), 179.14 (s, COO, bridging acetate)
178.43 (s, COO, bridging acetate), 176.74 (s, COO, terminal
2
[P t{CH2-C6H4-P (o-tolyl)2-KC,P }(a ca c-O,O′)] (1). To a sus-
pension of [{Pt{CH2-C6H4-P(o-tolyl)2-κC,P}(µ-Cl)}2] (1.0075 g,
0.944 mmol) in CHCl3 (30 mL) was added Tl(acac) (0.5726 g,
1.887 mmol), and the mixture was refluxed for 3 h. The TlCl
formed was removed by filtration. After evaporation of the
solution to dryness and addition of n-pentane (20 mL) to the
residue, a white solid was isolated, 1 (0.992 g, 88%). Anal.
Calcd for C26H27O2PPt: C, 52.26; H, 4.55. Found: C, 52.29;
H, 4.41. IR: 1591 (vs), 1569 (vs), 1520 (vs), 1271 (s), 790 (s),
774 (vs), 760 (vs), 744 (vs), 605 (s), 591 (s), 566 (s), 532 (s),
522 (m), 510 (m), 488 (s), 481 (s), 462 (s), 445 (m). 31P{1H}
3
acetate), 30.12 (s, CH3, acac), 26.64 (d, J P-C ) 9.1 Hz, CH3,
4
C∧P), 24.28 (s, CH3, bridging acetate), 23.75 (d, J P-C ) 6.2
Hz, CH3, bridging acetate), 22.61 (s, CH3, C∧P), 21.94 (s CH3,
terminal acetate), 15.88 (s, J Pt-C ) 647.1 Hz, CH2, C∧P).
[P t{CH2-C6H4-P (o-tolyl)2-KC,P }(µ-O2CCF3)2Hg(µ3-acac2-
-
KC3,O)Hg(O2CCF 3-KO)]2 (5). Complex 5 was prepared in
manner similar to that for complex 4. 1 (0.1857 g, 0.317 mmol),
Hg(O2CCF3)2 (0.2705 g, 0.634 mmol), T ) -5 °C. Yield )
0.3116 g, 75%. Anal. Calcd for C64H52F18Hg4O16P2Pt2: C, 28.75;
H, 1.96. Found: C, 28.51; H, 1.76. IR: 1788 (m), 1658 (vs),
1190 (vs), 854 (vs), 788 (s), 756 (s), 671 (w), 614 (m), 590 (s),
565 (s), 526 (s), 505 (w), 488 (w), 476 (m), 458 (m). 31P{1H}
1
NMR (CDCl3, 293 K): 11.10 (s, J Pt-P ) 4734.1 Hz). H: 7.5-
6.7 (m, C6H4, C∧P), 5.34 (s, C3-H, acac), 3.65 (νA), 3.47 (νB)
(2J H-H ) 13.79 Hz, CH2, C∧P), 2.82 (s, CH3, C∧P), 2.43 (s, CH3,
C∧P), 1.92 (s CH3, acac), 1.75 (s CH3, acac). 13C{1H} NMR:
3
185.43 (s, CO, acac), 183.61 (s, CO, acac), 101.15 (s, J Pt-C
)
1
54.8 Hz, C3, acac), 28.24 (s, CH3, acac), 27.62 (d, J P-C ) 6.4
Hz, CH3, acac), 22.84 (s, CH3, C∧P), 22.31 (s, CH3, C∧P), 10.86
(s, J Pt-C ) 763.4 Hz, CH2, C∧P).
4
NMR (CDCl3, 293 K): 14.76 (s, J Pt-P ) 3619.6 Hz). H NMR:
2
7.7-7.0 (m, C6H4, C∧P), 4.42 (s, J Pt-H ) 160.2 Hz, 1H, CH2,
C∧P), 4.42 (s, 2J Pt-H ) 126.6 Hz, 1H, CH2, C∧P), 3.10 (s, CH3,
C∧P), 2.05 (s, CH3, acac), 2.01 (s, CH3, C∧P). 19F{1H} NMR:
-73.63 (s, CF3), -73.50 (s, CF3), -72.99 (s, CF3). 13C{1H}
NMR: 30.15 (s, CH3, acac), 27.00 (s, CH3, C∧P), 22.64 (s, CH3,
C∧P), 14.23 (s, CH2, C∧P).
[P t{CH2-C6H4-P (o-tolyl)2-KC,P }(a ca c-O,O′)HgI(µ-I)]2 (2).
To a colorless solution of compound 1 (0.252 g, 0.422 mmol) in
Et2O/CH2Cl2 (80/7 mL) was added HgI2 (0.191 g, 0.422 mmol),
and the mixture was stirred for 1 h. The resulting yellow
solution was evaporated to dryness, and Et2O (25 mL) was
added to the residue to afford a yellow solid, 2 (0.326 g, 74%).
X-r a y Cr ysta l Str u ctu r e Deter m in a tion s. Suitable crys-
tals of 3 were obtained by slow diffusion of n-hexane into
CH2Cl2 solutions of complex 3 at 5 °C. Suitable crystals of 4‚
CHCl3 were obtained by slow diffusion of n-hexane into CHCl3
solutions of complex 4 at 5 °C.
Anal. Calcd for
C52H54Hg2I4O4P2Pt2: C, 29.68; H, 2.59.
Found: C, 29.32; H, 2.35. IR: 1565 (vs), 1527 (vs), 1275 (s),
787 (m), 754 (s), 745 (m), 611 (m), 590 (m), 567 (m), 531 (m),
523 (m), 506 (m), 488 (m), 479 (w), 458 (m). 31P{1H} NMR
(CDCl3, 293 K): 10.10 (s, J Pt-P ) 4527.3 Hz).1H NMR: 7.6-
Crystal data and other details of the structure analyses are
presented in Table 1. Crystals were fixed on top of glass or