η3-propargyl/allenyl complexes of platinum and palladium of the type [(PPh3)2M(η3-CH2CCR)] +

Article abstract of DOI:10.1021/om9506678

A study is reported on the synthesis, spectroscopic properties, molecular structure, and reaction chemistry of η₃-propargyl/allenyl complexes of platinum and palladium of the type [(PPh₃)₂M(η³-CH₂CCR)] ⁺ (M = Pt, R = Ph (1a), Me (2b); M = Pd, R = Ph (2a), Me (2b)). Complexes 1a,b were obtained by each of the following methods: (i) reaction of trans-(PPh₃)₂-PtBr(η¹-CH ₂C≡CPh) with AgO₃SCF₃; (ii) treatment of (PPh₃)₂Pt(≡₂-PhC=CCH₂OMe) with BF₃·OEt₂; (iii) addition of RC≡CCH₂OS(O)₂C₆H₄Me-P to (PPh₃)₂Pt(η²-C₂H₄) in solution. Complexes 2a,b resulted upon (i) abstraction of Br from trans-(PPh₃)₂PdBr(η¹-CH ₂C≡CR)/ trans-(PPh₃)₂PdBr(η¹-C(R)=C=CH₂) with AgBF₄ and (ii) treatment of Pd₂(dba)₃·CHCl₃ with PPh₃ and RC=CCH₂OS(O)₂C₆H₄Me-P. The structures of 1a(OTf)·CH₂Cl₂ (Tf= O₂SCF₃) and 2a(BF₄) were determined by X-ray diffraction techniques. Both cationic metal complexes show remarkably similar structures, the salient features being the attachment to the metal of all three propargyl/allenyl carbon atoms of the nonlinear C₃ fragment (C(1)-C(2)-C(3) bond angles: 152.2(9)° for 1a, 154.7(5)° for 2a) and the essentially coplanar arrangement of the three carbon, two phosphorus, and platinum or palladium atoms. 1a,b react readily with MeOH and Et₂NH to afford the corresponding complexes [(PPh₃)₂Pt(η₃-CH₂C(X)CHR)] ⁺ (X = OMe, NEt₂); 2a,b behave analogously, except that the reaction with MeOH requires trace amounts of NaOMe or NEt₃. ¹H and ¹³C NMR spectroscopic data suggest that the reaction products are best formulated as resonance hybrids of η³-allyl and metallacyclic structures.

Full text of DOI:10.1021/om9506678

164
Organometallics 1996, 15, 164-173
η3-P r op a r gyl/Allen yl Com p lexes of P la tin u m a n d
P a lla d iu m of th e Typ e [(P P h 3)2M(η3-CH2CCR)]+
Mark W. Baize, Patrick W. Blosser, Ve´ronique Plantevin, David G. Schimpff,
J udith C. Gallucci, and Andrew Wojcicki*
Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
Received August 25, 1995X
A study is reported on the synthesis, spectroscopic properties, molecular structure, and
reaction chemistry of η3-propargyl/allenyl complexes of platinum and palladium of the type
[(PPh3)2M(η3-CH2CCR)]+ (M ) Pt, R ) Ph (1a ), Me (1b); M ) Pd, R ) Ph (2a ), Me (2b)).
Complexes 1a ,b were obtained by each of the following methods: (i) reaction of trans-(PPh3)2-
PtBr(η1-CH2CtCPh) with AgO3SCF3; (ii) treatment of (PPh3)2Pt(η2-PhCtCCH2OMe) with
BF3‚OEt2; (iii) addition of RCtCCH2OS(O)2C6H4Me-p to (PPh3)2Pt(η2-C2H4) in solution.
Complexes 2a ,b resulted upon (i) abstraction of Br- from trans-(PPh3)2PdBr(η1-CH2CtCR)/
trans-(PPh3)2PdBr(η1-C(R)dCdCH2) with AgBF4 and (ii) treatment of Pd2(dba)3‚CHCl3 with
PPh3 and RCtCCH2OS(O)2C6H4Me-p. The structures of 1a (OTf)‚CH2Cl2 (Tf ) O2SCF3) and
2a (BF4) were determined by X-ray diffraction techniques. Both cationic metal complexes
show remarkably similar structures, the salient features being the attachment to the metal
of all three propargyl/allenyl carbon atoms of the nonlinear C3 fragment (C(1)-C(2)-C(3)
bond angles: 152.2(9)° for 1a , 154.7(5)° for 2a ) and the essentially coplanar arrangement of
the three carbon, two phosphorus, and platinum or palladium atoms. 1a ,b react readily
with MeOH and Et2NH to afford the corresponding complexes [(PPh3)2Pt(η3-CH2C(X)CHR)]+
(X ) OMe, NEt2); 2a ,b behave analogously, except that the reaction with MeOH requires
trace amounts of NaOMe or NEt3. 1H and 13C NMR spectroscopic data suggest that the
reaction products are best formulated as resonance hybrids of η3-allyl and metallacyclic
structures.
In tr od u ction
This paper focuses on cationic platinum and pal-
ladium η3-propargyl/allenyl complexes of the type
[(PPh3)2M(η3-CH2CCR)]+ (M ) Pt (1), Pd (2); R ) Ph
(a ), Me (b)). Since analogous η3-allyl complexes readily
In recent years there has been a considerable surge
of interest in transition-metal η3- (or π-) propargyl/
allenyl complexes (I).1 The propargyl and the allenyl
ligands, like the allyl ligand, can coordinate to a metal
center in a σ or π manner. In the latter, all three
skeletal carbon atoms are ligated, and the two different
C3 groups become resonance representations of one and
the same species. That mode of bonding was first
realized for metal η3-butenynyl complexes (II),2 which
are closely related to I. Subsequently, metal η3-prop-
argyl/allenyl complexes have been prepared for molyb-
denum,3 tungsten,4 rhenium,4,5 zirconium,6 platinum,7-9
and palladium.10,11
undergo addition of nucleophilic reagents to the allyl
ligand, and since such reactions are of great synthetic7
value for palladium,12 it was of considerable interest to
investigate related chemistry of the η3-propargyl/allenyl
complexes 1 and 2. In fact, a number of organic
transformations are known that involve use of propar-
gylic and similar unsaturated compounds in conjunction
(4) Krivykh, V. V. Organomet. Chem. USSR (Engl. Transl.) 1992,
5, 113; Metallorg. Khim. 1992, 5, 213.
(5) Casey, C. P.; Yi, C. S. J . Am. Chem. Soc. 1992, 114, 6597.
(6) Blosser, P. W.; Gallucci, J . C.; Wojcicki, A. J . Am. Chem. Soc.
1993, 115, 2994.
(7) Blosser, P. W.; Schimpff, D. G.; Gallucci, J . C.; Wojcicki, A.
Organometallics 1993, 12, 1993.
X Abstract published in Advance ACS Abstracts, December 1, 1995.
(1) Reviews: (a) Wojcicki, A. New J . Chem. 1994, 18, 61. (b) Doherty,
S.; Corrigan, J . F.; Carty, A. J .; Sappa, E. Adv. Organomet. Chem. 1995,
37, 39.
(2) (a) Gotzig, J .; Otto, H.; Werner, H. J . Organomet. Chem. 1985,
287, 247. (b) J ia, G., Rheingold, A. L.; Meek, D. W. Organometallics
1989, 8, 1378. (c) Bianchini, C.; Peruzzini, M.; Zanobini, F.; Frediani,
P.; Albinati, A. J . Am. Chem. Soc. 1991, 113, 5453. (d) McMullen, A.
K.; Selegue, J . P.; Wang, J . G. Organometallics 1991, 10, 3421. (e) Hills,
A.; Hughes, D. L.; J imenez-Tenorio, M.; Leigh, G. J .; McGeary, C. A.;
Rowley, A. T.; Bravo, M.; McKenna, C. E.; McKenna, M.-C. J . Chem.
Soc., Chem. Commun. 1991, 522. (f) Field, L. D.; George, A. V.;
Hambley, T. W. Inorg. Chem. 1990, 29, 4565.
(8) (a) Huang, T.-M.; Chen, J .-T.; Lee, G.-H.; Wang, Y. J . Am. Chem.
Soc. 1993, 115, 1170. (b) Huang, T.-M.; Hsu, R.-H.; Yang, C.-S.; Chen,
J .-T.; Lee, G.-H.; Wang, Y. Organometallics 1994, 13, 3657.
(9) Stang, P. J .; Crittell, C. M.; Arif, A. M. Organometallics 1993,
12, 4799.
(10) Baize, M. W.; Gallucci, J .; Wojcicki, A. Abstracts of Papers, 210th
ACS National Meeting, Chicago, IL, August 20-24, 1995; American
Chemical Society: Washington, DC, 1995; INOR140 (abstract submit-
ted by Apr 17, 1995).
(3) Krivykh, V. V.; Taits, E. S.; Petrovskii, P. V.; Struchkov, Yu. T.;
Yanovskii, A. I. Mendeleev Commun. 1991, 103.
(11) Ogoshi, S.; Tsutsumi, K.; Kurosawa, H. J . Organomet. Chem.
1995, 493, C19.
0276-7333/96/2315-0164$12.00/0 © 1996 American Chemical Society

Pt and Pd η3-Propargyl/ Allenyl Complexes
Organometallics, Vol. 15, No. 1, 1996 165
1
with palladium complexes.13 Some of these reactions
may well proceed by intermediacy of palladium η3-
propargyl/allenyl species.
We describe herein a comparative study of the chem-
istry of 1 and 2, with emphasis on methods of synthesis,
spectroscopic properties, solid-state structure, and some
reactions with nucleophiles. A more extensive investi-
gation of the reaction chemistry of these complexes will
be reported later.14 Some aspects of our study have
already been communicated.15
2.45 g (98%); H NMR (CD2Cl2) δ 7.9-7.0 (m, Ph), 2.17 (dd,
J PH ) 8.9, 6.3 Hz, J PtH ) 77 Hz, CH2); 31P{1H} NMR (CD2Cl2)
δ 18.7 (d, J PP ) 16.4 Hz, J PtP ) 1906 Hz), 17.8 (d, J PP ) 16.4
Hz, J PtP ) 4493 Hz), 17.3 (d, J PP ) 16.7 Hz, J PtP ) 1928 Hz),
15.2 (d, J PP ) 16.7 Hz, J PtP ) 4351 Hz); IR (Nujol) ν(CtC)
2160 cm-1. Anal. Calcd for C45H37BrP2Pt: C, 59.09; H, 4.08.
Found: C, 59.29; H, 4.08.
P r ep a r a tion of tr a n s-(P P h 3)2P tBr (η1-CH2CtCP h ).
A
solution of cis-(PPh3)2PtBr(η1-CH2CtCPh) (2.45 g, 2.68 mmol)
in 200 mL of THF was stirred for 2 h at 55 °C under an Ar
atmosphere. All solvent was then removed under vacuum, and
the product was dried for 2 h. The yellow solid was triturated
with 200 mL of hexane, collected on a filter frit in air, and
dried overnight: Yield 2.35 g (96%); 1H NMR (CD2Cl2) δ 8.0-
7.0 (m, Ph), 1.39 (t, J PH ) 8.1 Hz, J PtH ) 103 Hz, CH2); 13C
Exp er im en ta l Section
Gen er a l P r oced u r es a n d Mea su r em en ts. All reactions
and manipulations of air- and moisture-sensitive compounds
were carried out under an atmosphere of dry Ar by use of
standard procedures.16 Elemental analyses were performed
by M-H-W Laboratories, Phoenix, AZ, and Atlantic Microlab,
Inc., Norcross, GA. Melting points were measured on a
Thomas-Hoover melting point apparatus and are uncorrected.
Infrared, NMR (1H, 13C, 19F, and 31P), and FAB mass spectra
were obtained as previously described.17,18
NMR (CD2Cl2) δ 135-126 (m, Ph), 95.7 (s, J PtC ) 96 Hz, CPh),
1
81.7 (s, J PtC ) 42 Hz, CH2C), -5.5 (tt, J CH ) 140 Hz, J PC
)
3.9 Hz, J PtC ) 637 Hz, CH2); 31P{1H} NMR (CD2Cl2) δ 24.7 (s,
J PtP ) 3144 Hz); IR (Nujol) ν(CtC) 2175 cm-1. Anal. Calcd
for C45H37BrP2Pt: C, 59.09; H, 4.08. Found: C, 58.96; H, 4.06.
P r ep a r a t ion
of
[(P P h 3)2P t (η3-CH2CCP h )]O3SCF 3
(1a (OTf)) fr om tr a n s-(P P h 3)2P t Br (η1-CH2CtCP h ) a n d
AgO3SCF 3. A solution of AgO3SCF3 (0.634 g, 2.45 mmol) in
25 mL of THF was added to a solution of trans-(PPh3)2PtBr-
(η1-CH2CtCPh) (2.23 g, 2.44 mmol) in 225 mL of THF. A pale
yellow precipitate began to form upon mixing. The slurry was
vigorously stirred for 3 h and then filtered through a filter
frit to remove the precipitated AgBr. The filtrate was evapo-
rated to dryness under vacuum, and 30 mL of CH2Cl2 was
added to the residue. The resulting slightly cloudy solution
was filtered through a filter frit, and the clear brown filtrate
was concentrated to ca. 5 mL. The addition of 100 mL of
hexane induced precipitation of the beige product. The volume
of the solution was reduced to 50 mL, and the product was
collected on a filter frit and dried under vacuum for 3 days:
Ma ter ia ls. All solvents were dried, distilled under an Ar
atmosphere, and degassed before use.19 Reagents were ob-
tained from various commercial sources and used as received.
Literature procedures were followed to synthesize PhCtCCH2-
Br,20 MeCtCCH2Br,21 PhCtCCH2OMe,22 PhCtCCH2OS-
(O)2C6H4Me-p,23 MeCtCCH2OS (O)2C6H4Me-p,23 (PPh3)2Pt(η2-
26
C2H4),24 Pd(PPh3)4,25 and Pd2(dba)3‚CHCl3
dibenzylideneacetone).
(dba
)
P r ep a r a tion of cis-(P P h 3)2P tBr (η1-CH2CtCP h ). Phe-
nylpropargyl bromide (0.50 mL, 4.0 mmol) was added dropwise
to a stirred suspension of (Ph3P)2Pt(η2-C2H4) (2.05 g, 2.74
mmol) in 40 mL of hexane at 0 °C. After 20 min the ice bath
was removed, and vigorous stirring continued for 2 h as the
color of the suspended solid changed from white to yellow. The
solid was then collected on a filter frit in air, washed twice
with 30 mL of diethyl ether, and dried under vacuum: Yield
1
Yield 2.30 g (96%); H NMR (CD2Cl2) δ 7.5-6.5 (m, Ph), 2.74
(d, J PH ) 6.8 Hz, J PtH ) 29.9 Hz, CH2); 13C NMR (CD2Cl2) δ
135-128 (m, Ph), 102.1 (dd, J PC ) 47, 1.5 Hz, J PtC ) 93 Hz,
CPh), 97.3 (dd, J PC ) 4.8, 3.2 Hz, J PtC ) 63 Hz, CH2C), 48.3
(td, J CH ) 170 Hz, J PC ) 37 Hz, J PtC )126 Hz, CH2); 31P{1H}
1
(12) Selected reviews: (a) Collman, J . P.; Hegedus, L. S.; Norton,
J . R.; Finke, R. G. Principles and Applications of Organotransition
Metal Chemistry; University Science Books: Mill Valley, CA, 1987;
pp 417, 881. (b) Tsuji, J . Tetrahedron 1986, 42, 4361. (c) Ba¨ckvall, J .
E. Acc. Chem. Res. 1983, 16, 335. (d) Tsuji, J . Pure Appl. Chem. 1982,
54, 197. (e) Trost, B. M. Acc. Chem. Res. 1980, 13, 385.
NMR (CD2Cl2) δ 15.4 (d, J PP ) 18.7 Hz, J PtP ) 3785 Hz), δ
10.5 (d, J PP ) 18.7 Hz, J PtP ) 4285 Hz); 19F{1H} NMR (CD2-
Cl2) δ -78.9 (s). Anal. Calcd for C46H37F3O3P2PtS: C, 56.16;
H, 3.79. Found: C, 55.91; H, 4.02.
P r ep a r a tion of (P P h 3)2P t(η2-P h CtCCH2OMe). Methyl
phenylpropargyl ether (0.18 mL, 1.1 mmol) was added drop-
wise to a stirred solution of (PPh3)2Pt(η2-C2H4) (0.75 g, 1.0
mmol) in 30 mL of THF at -78 °C. The resulting solution
was slowly warmed to ambient temperature over 8 h, and all
volatiles were removed under vacuum. The residue was
washed twice with 50-mL portions of hexane, and the pale
yellow solid was collected on a filter frit and dried overnight:
Yield 0.82 g (94%). 1H NMR (CD2Cl2) δ 7.6-7.1 (m, Ph), 4.06
(t, J PH ) 2.3 Hz, J PtH ) 14 Hz, CH2), 3.16 (s, Me); 31P{1H} NMR
(CD2Cl2) δ 28.0 (d, J PP ) 32 Hz, J PtP ) 3518 Hz), 24.6 (d, J PP
) 32 Hz, J PtP ) 3439 Hz); MS (FAB), 195Pt isotope, m/z 866
(M++1), 719 (M+ - PhCCCH2OMe).
(13) Selected publications: (a) Mandai, T.; Tsujiguchi, Y.; Matsuoka,
S.; Saito, S.; Tsuji, J . J . Organomet. Chem. 1995, 488, 127. (b) Mikami,
K.; Yoshida, A.; Matsumoto, S.; Feng, F.; Matsumoto, Y. Tetrahedron
Lett. 1995, 36, 907. (c) Mandai, T.; Matsumoto, T.; Tsujiguchi, T.;
Matsuoka, S.; Tsuji, J . J . Organomet. Chem. 1994, 473, 343. (d)
Mandai, T.; Tsujiguchi, Y.; Matsuoka, S.; Tsuji, J . Tetrahedron Lett.
1993, 34, 7615. (e) Bouyssi, D.; Gore, J .; Balme, G.; Louis, D.; Wallach,
J . Tetrahedron Lett. 1993, 34, 3129. (f) Minami, I.; Yuhara, M.;
Watanabe, H.; Tsuji, J . J . Organomet. Chem. 1987, 334, 225.
(14) Baize, M. W.; Blosser, P. W.; Daniel, K. L.; Furilla, J . L.;
Calligaris, M.; Faleschini, P.; Graham, J . P.; Bursten, B. E.; Wojcicki,
A. To be submitted for publication.
(15) (a) Pt (1a ): ref 7. (b) Pd (2a ,b): ref 10.
A preliminary
communication on 2a by another group appeared in print11 subsequent
to the submission of our abstract.
(16) Shriver, D. F.; Drezdzon, M. A. The Manipulation of Air-
Sensitive Compounds, 2nd ed.; Wiley: New York, 1986.
(17) Young, G. H.; Raphael, M. V.; Wojcicki, A.; Calligaris, M.;
Nardin, G.; Bresciani-Pahor, N. Organometallics 1991, 10, 134.
(18) Young, G. H.; Willis, R. R.; Wojcicki, A.; Calligaris, M.;
Faleschini, P. Organometallics 1992, 11, 154.
(19) Perrin, D. D.; Armarego, W. L. F.; Perrin, D. R. Purification of
Laboratory Chemicals; Pergamon: Oxford, U.K., 1966.
(20) Brandsma, L.; Verkruijsse, H. D. Synthesis of Acetylenes,
Allenes, and Cumulenes; Elsevier: New York, 1981; p 219.
(21) Ashworth, P. J .; Whitham, G. H.; Whiting, M. C. J . Chem. Soc.
1957, 4633.
(22) Stoochnoff, B. A.; Benoiton, N. L. Tetrahedron Lett. 1973, 1,
21.
(23) Reference 20, pp 223-224.
(24) Blake, D. M.; Roundhill, D. M.; Ambridge, C.; Dwite, S.; Clark,
H. C. Inorg. Synth. 1978, 18, 120.
P r ep a r a tion of [(P P h 3)2P t(η3-CH2CCP h )]BF 3OMe (1a -
(BF 3OMe)) fr om (P P h 3)2P t (η2-P h CtCCH2OMe) a n d
BF 3‚OEt2. To a mixture of (PPh3)2Pt(η2-PhCtCCH2OMe)
(0.55 g, 0.64 mmol) in 50 mL of diethyl ether at 0 °C was added
BF3‚OEt2 (0.06 mL, 0.7 mmol). After 15 min of stirring, the
contents were warmed to room temperature and stirred for
an additional 1 h. The pale yellow solid was filtered off,
washed first with diethyl ether (50 mL) and then with hexane
(50 mL), and dried under vacuum overnight: Yield 0.56 g
(92%). The product was characterized by comparison of its
1H and 31P{1H} NMR spectra with those of 1(OTf).
In Situ P r ep a r a t ion of [(P P h 3)2P t (η3-CH 2CCP h )]-
O3SC6H 4Me-p (1a (OTs)) fr om (P P h 3)2P t (η2-C2H 4) a n d
P h CtCCH 2OS(O)2C6H 4Me-p . Solutions of (PPh3)2Pt(η2-
C2H4) (0.050 g, 0.067 mmol) in 2 mL of CH2Cl2 and PhCtCCH2-
(25) Coulson, D. R. Inorg. Synth. 1990, 28, 107.
(26) Ukai, T.; Kawazawa, H.; Ishii, Y.; Bonnett, J . J .; Ibers, J . A. J .
Organomet. Chem. 1974, 65, 253.

166 Organometallics, Vol. 15, No. 1, 1996
Baize et al.
OS(O)2C6H4-p (0.019 g, 0.067 mmol) in 1 mL of CH2Cl2 were
prepared in a drybox. The phenylpropargyl tosylate solution
was added dropwise to the solution of (PPh3)2Pt(η2-C2H4) at
-78 °C, and the contents were stirred for 3 h, during which
time the temperature was allowed to rise slightly. The
reaction solution was concentrated, and the 31P{1H} NMR
spectrum was recorded and found to be essentially identical
with that of 1a (OTf). Attempts at isolation of 1a (OTs),
performed in the drybox, invariably resulted in decomposition
to unidentified materials.
In Situ P r ep a r a t ion of [(P P h 3)2P t (η3-CH2CCMe)]-
O3SC6H 4Me-p (1b (OTs)] fr om (P P h 3)2P t (η2-C2H 4) a n d
MeCtCCH2OS(O)2C6H4Me-p. The procedure was similar to
that for 1a (OTs). 31P{1H} NMR: δ 18.8 (d, J PP ) 17.4 Hz, J PtP
) 4240 Hz), 12.6 (d, J PP ) 17.4 Hz, J PtP ) 3754 Hz). The
product decomposed during isolation workup.
CCH2OS(O)2C6H4Me-p. A solution of Pd2(dba)3‚CHCl3 (0.250
g, 0.483 mmol of Pd) and PPh3 (0.254 g, 0.968 mmol) in 20
mL of CH2Cl2 was stirred at room temperature for 5 min and
then treated with PhCtCCH2OS(O)2C6H4Me-p (0.138 g, 0.483
mmol). Almost immediately the color of the solution changed
from red-purple to orange. The reaction solution was stirred
for 15 min at room temperature, concentrated to ca. 2 mL, and
filtered through Celite. Addition of 20 mL of diethyl ether to
the filtrate induced the precipitation of 2a (OTs) as a pale
yellow solid. The product was collected on a filter frit, washed
with 20 mL of diethyl ether, and dried overnight under
vacuum: Yield 0.334 g (81%). Characterization was effected
1
by comparison of its H, 13C{1H}, and 31P{1H} NMR and FAB
mass spectra with those of 2a (BF4). Anal. Calcd for
C
52H44O3P2PdS: C, 68.09; H, 4.83. Found: C, 67.79; H, 4.98.
P r ep a r a tion of [(P P h 3)2P d (η3-CH2CCMe)]O3SC6H4Me-
(2b (OTs)) fr om P d 2(d b a )3‚CH Cl3, P P h 3, a n d MeCt
P r ep a r a t ion of tr a n s-(P P h 3)2P d Br (η1-CH 2CtCP h )/
tr a n s-(P P h 3)2P d Br (η1-C(P h )dCdCH2). Pd(PPh3)4 (3.0 g,
2.6 mmol) in 100 mL of THF was treated with PhCtCCH2Br
(0.53 g, 2.7 mmol). The resulting yellow solution was stirred
at 25 °C for 30 min and concentrated to 50 mL under reduced
pressure. The addition of 100 mL of hexane gave a yellow
precipitate, which was collected on a filter frit and washed with
40 mL of diethyl ether. The product was dried under vacuum
overnight: Yield 2.10 g (97%), with the approximate product
p
CCH2OS(O)2C6H4Me-p. This complex was prepared similarly
to 2a (OTs) from Pd2(dba)3‚CHCl3 (0.250 g, 0.483 mmol of Pd),
PPh3 (0.254 g, 0.968 mmol), and MeCtCCH2OS(O)2C6H4Me
(0.108 g, 0.483 mmol) to give 2b(OTs) as a white solid: Yield
0.343 g (83%). Characterization was effected by comparison
of its 1H, 13C{1H}, and 31P{1H} NMR and FAB mass spectra
with those of 2b(BF4). Anal. Calcd for C47H42O3P2PdS: C,
66.01; H, 4.95. Found: C, 65.78; H, 5.03.
1
Reaction of [(P P h 3)2P t(η3-CH2CCP h )]+ (1a) with MeOH.
Methanol (1.5 mL, 3.7 mmol) was added to a stirred solution
of 2a (OTf) (0.200 g, 0.203 mmol) in 3 mL of CH2Cl2. After 5
min all solvent was removed under vacuum, and the residue
was dissolved in 3 mL of CH2Cl2. A 30-mL portion of hexane
was added to induce the precipitation of a beige product. After
the volume of the solution had been reduced to 15 mL, the
solid was collected on a filter frit and washed with 5 mL of
hexane. The product [(PPh3)2Pt(η3-CH2C(OMe)CHPh)]O3SCF3
(3a (OTf)) was dried under vacuum at 60 °C for 2 days: Yield
0.180 g (87%); 1H NMR (CDCl3) δ 7.5-6.6 (m, Ph), 4.41 (d,
J PH ) 10.5 Hz, J PtH ) 39.8 Hz, CHPh), 3.50 (s, OMe), 3.21
ratio of 1:2, propargyl to allenyl; H NMR (CD2Cl2) δ 7.8-6.6
(m, Ph), 3.62 (s, CH2d), 1.71 (s, PdCH2); 31P{1H} NMR (CD2-
Cl2) δ 26.1 (br, propargyl complex), 22.9 (s, allenyl complex).
Anal. Calcd for C45H37BrP2Pd: C, 65.43; H, 4.51. Found: C,
65.28; H, 4.58.
P r ep a r a t ion of tr a n s-(P P h 3)2P d Br (η1-CH 2CtCMe)/
tr a n s-(P P h 3)2P d Br (η1-C(Me)dCdCH2). This mixture was
prepared as described above for the Ph analogue from Pd-
(PPh3)4 (3.0 g, 2.6 mmol) and MeCtCCH2Br (0.36 g, 2.7
mmol): Yield 1.88 g (95%) of a yellow solid, approximate
product ratio 3:1, propargyl to allenyl; 1H NMR (C6D6/CD2Cl2,
1:1) δ 7.8-7.0 (m, Ph), 3.44 (s, CH2d), 1.59 (s, PdCH2), 1.45
(s, Me); 31P{1H} NMR (CD2Cl2) δ 25.1 (br, propargyl complex),
22.7 (s, allenyl complex). Anal. Calcd for C40H35BrP2Pd: C,
62.89; H, 4.62. Found: C, 62.73; H, 4.72.
2
(dd, J PH ) 9.7 Hz, J HH ) 6.6 Hz, J PtH ) 35 Hz, Hanti of CH2),
2.86 (m, Hsyn of CH2); 13C{1H} NMR (CDCl3) δ 148.6 (s, CCH2),
135-123 (m, Ph), 68.7 (d, J PC ) 36.8 Hz, J PtC ) 74.1 Hz,
CHPh), 53.9 (s, OMe), 48.9 (d, J PC ) 34.7 Hz, J PtC ) 127 Hz,
P r ep a r a tion of [(P P h 3)2P d (η3-CH2CCP h )]BF 4 (2a (BF 4))
fr om tr a n s-(P P h 3)2P d Br (η1-CH 2CtCP h )/tr a n s-(P P h 3)2-
P d Br (η1-C(P h )dCdCH2) a n d AgBF 4. A solution of AgBF4
(0.118 g, 0.60 mmol) in 5 mL of THF was added to a stirred
solution of trans-(PPh3)2PdBr(η1-CH2CtCPh)/trans-(PPh3)2-
PdBr(η1-C(Ph))CdCH2) (0.50 g, 0.60 mmol) in 25 mL of CH2-
Cl2. A precipitate of AgBr formed almost immediately. The
mixture was stirred for 15 min at room temperature, AgBr
was removed by filtration, and the volume of the solution was
reduced to ca. 5 mL. Slow addition of 25 mL of diethyl ether
gave a pale yellow precipitate. The solid was collected on a
filter frit, washed with 20 mL of diethyl ether, and dried under
CH2); 31P{1H} NMR (CDCl3) δ 18.1 (d, J PP ) 9.5 Hz, J PtP
)
3824 Hz), δ 13.6 (d, J PP ) 9.5 Hz, J PtP ) 3783 Hz); 19F{1H}
NMR (CDCl3) δ -79.0 (s). Anal. Calcd for C47H41F3O4P2PtS:
C, 55.57; H, 4.07. Found: C, 55.36; H, 4.30.
Reaction of [(P P h 3)2P t(η3-CH2CCP h )]+ (1a) with Et2NH.
Diethylamine (0.10 mL, 0.97 mmol) was added to a stirred
solution of 1a (OTf) (0.219 g, 0.223 mmol) in 3 mL of CH2Cl2.
After 5 min, 30 mL of hexane was introduced to induce
precipitation of the product. The volume of the solution was
reduced to 15 mL, and the beige solid was collected on a filter
frit and washed with 5 mL of hexane. The product [(PPh3)2-
Pt(η3-CH2C(NEt2)CHPh)]O3SCF3 (4a (OTf)) was dried under
vacuum at 60 °C for 2 days: Yield 0.203 g (86%); 1H NMR
(CDCl3) δ 7.7-6.8 (m, Ph), 4.38 (m, CHPh), 3.27 (m, NCH2),
1
vacuum: Yield 0.45 g (90%); H NMR (CD2Cl2) δ 7.5-6.8 (m,
Ph), 3.19 (dd, J PH ) 7.8, 1.5 Hz, CH2); 13C{1H} NMR (CD2Cl2)
δ 135-120 (m, Ph), 105.4 (d, J PC ) 41.3 Hz, CPh), 94.2 (m,
CH2C), 50.9 (d, J PC ) 41 Hz, CH2; 31P{1H} NMR (CD2Cl2) δ
29.1 (d, J PP ) 46.6 Hz), 27.9 (d, J PP ) 46.6 Hz); MS (FAB),
106Pd isotope, m/z 745 (M+).
2
2.62 (m, Hsyn of CH2), 2.33 (dd, J PH ) 11.4 Hz, J HH ) 7.7 Hz,
J PtH ) 60 Hz, Hanti of CH2), 1.07 (br, Me); 13C{1H} NMR (CDCl3)
δ 152.5 (s, J PtC ) 123 Hz, CCH2), 136-124 (m, Ph), 57.0 (d,
J PC ) 51.7 Hz, J PtC ) 236 Hz, CHPh), 41.7 (s, NCH2), 35.0 (d,
J PC ) 47.4 Hz, J PtC )184 Hz, CCH2), 10.7 (s, Me); 31P{1H} NMR
(CDCl3) δ 17.2 (d, J PP ) 8.5 Hz, J PtP ) 3359 Hz), δ 14.5 (d, J PP
) 8.5 Hz, J PtP ) 3025 Hz); 19F{1H} NMR (CDCl3) δ -79.1 (s).
P r ep a r a tion of [(P P h 3)2P d (η3-CH2CCMe)]BF 4 (2b(BF 4))
fr om tr a n s-(P P h 3)2P d Br (η1-CH 2CtCMe)/tr a n s-(P P h 3)2-
P d Br (η1-C(Me)dCdCH2) a n d AgBF 4. This complex was
prepared as above from trans-(PPh3)2PdBr(η1-CH2CtCMe)/
trans(PPh3)2PdBr(η1-C(Me)dCdCH2) (0.50 g, 0.65 mmol) and
AgBF4 (0.126 g, 0.65 mmol) and isolated as a pale yellow
solid: Yield 0.464 g (92%); 1H NMR (CD2Cl2) δ 7.5-7.1 (m,
Ph), 3.22 (m, CH2), 1.33 (m, Me); 13C{1H} NMR (CD2Cl2) δ
134-128 (m, Ph), 103.0 (d, J PC ) 43.9 Hz, CPh), 91.2 (m,
CH2C), 53.1 (m, CH2), 6.4 (s, Me); 31P{1H} NMR (CD2Cl2) δ
30.2 (d, J PP ) 43.9 Hz), 27.8 (d, J PP ) 43.9 Hz); MS (FAB),
106Pd isotope, m/z 683 (M+).
Anal. Calcd for
C50H48F3NO3P2PtS: C, 56.82; H, 4.58.
Found: C, 56.57; H, 4.81.
4a was also obtained, as 4a (OTs), by generating 1a (OTs)
in situ, from (PPh3)2Pt(η2-C2H4) (0.050 g, 0.067 mmol) and
PhCtCCH2OS(O)2C6H4Me-p (0.020 g, 1 equiv), in the presence
of Et2NH (0.030 mL, 0.020 g, 4 equiv) in CH2Cl2 at -78 °C.
The temperature of the mixture was allowed to rise over 6 h,
and the completion of the reaction was ascertained by 31P{1H}
NMR spectroscopy. After evaporation of the solvent, the
residue was dissolved in 2 mL of CH2Cl2. An off-white solid
P r ep a r a t ion of [(P P h 3)2P d (η3-CH2CCP h )]O3SC6H 4-
Me-p (2a (OTs)) fr om P d 2(d ba )3‚CHCl3, P P h 3, a n d P h Ct

Pt and Pd η3-Propargyl/ Allenyl Complexes
Organometallics, Vol. 15, No. 1, 1996 167
precipitated upon addition of 15 mL of hexane and was isolated
by filtration and washed with 5-mL portions of hexane: Yield
0.045 g (61%). The product was characterized by comparison
of its 1H, 13C{1H}, and 31P{1H} NMR data with those of
4a (OTf).
(0.002 g, 0.037 mmol) in 1 mL of MeOH (27 mmol). Similar
reaction time and workup led to the isolation of the product
in 70% yield (0.291 g). Its spectroscopic properties agreed with
those of 5a (BF4). Anal. Calcd for C53H48O4P2PdS: C, 67.05;
H, 5.10. Found: C, 66.70; H, 5.34.
Reaction of [(P P h 3)2P d(η3-CH2CCMe)]+ (2b) with MeOH
a n d Ba se. All procedures were strictly analogous to those
for the corresponding reactions of 2a . By use of 2b(BF4) (0.250
g, 0.324 mmol), MeOH (1 mL), and NaOMe (0.002 g, 0.037
mmol) or NEt3 (1 drop), 0.245 g (94% yield) of [(PPh3)2Pd(η3-
CH2C(OMe)CHMe]BF4 (5b(BF4)), a beige solid, was isolated:
1H NMR (CD2Cl2) δ 7.6-7.0 (m, Ph), 3.55 (m, CHMe), 3.50 (s,
OMe), 3.04 (m, CH2), 0.81 (m, Me); 13C{1H} NMR (CD2Cl2) δ
Reaction of [(P P h 3)2P t(η3-CH2CCMe)]+ (1b) with MeOH.
The procedure was analogous to that described above for the
synthesis of 4a (OTs). A solution of (PPh3)2Pt(η2-C2H4) (0.050
g, 0.067 mmol) in 5 mL of CH2Cl2 at -78 °C was treated with
MeOH (2.0 mL, 1.59 g, 49.0 mmol) and MeCtCCH2OS(O)2-
C6H4Me-p (0.015 g, 1 equiv) in 1 mL of CH2Cl2. The mixture
was allowed to warm to room temperature and was worked-
up as in the immediately preceding reaction. [(PPh3)2Pt(η3-
CH2C(OMe)CHMe]O3SC6H4Me-p (3b(OTs)) was isolated in
61% yield (0.040 g) as an off-white solid: 1H NMR (CDCl3) δ
7.5-7.0 (m, Ph, C6H4), 3.49 (s, OMe), 3.48 (m, CHMe), 3.02
153.8 (t, J PC ) 6 Hz, CCH2), 134-128 (m, Ph), 76.5 (d, J PC
)
37 Hz, CHMe), 58.6 (d, J PC ) 33 Hz, CH2), 56.2 (s, OMe), 11.0
(s, Me); 31P{1H} NMR (CD2Cl2) δ 27.2 (d, J PP ) 38 Hz), 24.2
(d, J PP ) 38 Hz); MS (FAB), 106Pd isotope, m/ z 715 (M+). Anal.
Calcd for C41H39BF4OP2Pd: C, 61.33; H, 4.90. Found: C,
61.37; H, 4.97.
2
(dd, J PH ) 10.7 Hz, J HH ) 9.6 Hz, J PtH ) 33 Hz, Hanti of
CH2), 2.71 (br m, Hsyn of CH2), 2.28 (s, C6H4Me), 0.88 (m,
CHMe); 13C{1H} NMR (CDCl3) δ 152.6 (t, CCH2), 145-126 (m,
Ph, C6H4), 66.6 (d, J PC ) 37 Hz, J PtC ) 178 Hz, CHMe), 55.4
(s, OMe), 51.5 (d, J PC ) 35 Hz, J PtC ) 122 Hz, CH2), 21.9 (s,
C6H4Me), 10.0 (s, CHMe); 31P{1H} NMR (CDCl3) δ 20.6 (d, J PP
5b(OTs) was prepared similarly to 5a (OTs) either from
2b(OTs), MeOH, and NaOMe (or NEt3) or from Pd2(dba)3‚CHCl3,
PPh3, MeCtCCH2OS(O)2C6H4Me-p, MeOH, and NaOMe (or
NEt3). Comparable yields were obtained, and spectroscopic
properties of the product agreed with those of 5b(BF4).
No formation of 5b(OTs) was observed in the absence of
added base.
Reaction of [(P P h 3)2P d(η3-CH2CCP h )]+ (2a) with Et2NH.
Excess Et2NH (0.10 mL, 0.97 mmol) was added to a solution
of 2a (BF4) (0.250 g, 0.300 mmol) in 10 mL of CH2Cl2, the
resulting mixture was stirred for 10 min at room temperature,
and the volatiles were removed under reduced pressure. The
yellow residue was dissolved in minimum CH2Cl2, and 1 mL
of THF was added. Slow addition of 10 mL of Et2O induced
the precipitation of a pale yellow solid, which was collected
by filtration, washed with 10 mL of Et2O, and dried under
) 9.6 Hz, J PtP ) 3753 Hz), 15.2 (d, J PP ) 9.6 Hz, J PtP
3126 Hz).
)
Reaction of [(P P h 3)2P t(η3-CH2CCMe)]+ (1b) with Et2NH.
A solution of (PPh3)2Pt(η2-C2H4) (0.050 g, 0.067 mmol) in 5 mL
of CH2Cl2 at 0 °C was treated with Et2NH (0.015 mL, 0.011 g,
2.2 equiv) and MeCtCCH2OS(O)2C6H4Me-p (0.015 g, 1 equiv)
in 1 mL of CH2Cl2 to generate 1b(OTs) in the presence of the
amine. The mixture was stirred at 0 °C for 1 h, solvent was
removed under reduced pressure, and CH2Cl2 (5 mL) and Et2O
(5 mL) were added with stirring. The resulting clear solution
was separated from a yellow oil and pumped to dryness. The
residue was recrystallized from benzene/hexane to yield 0.030
g
(45%) of [(PPh3)2Pt(η3-CH2C(NEt2)CHMe]O3SC6H4Me-p
(4b(OTs)) as an off-white solid: 1H NMR (CDCl3) δ 7.9-7.1
(m, Ph, C6H4), 3.15 (m, NCH2), 2.92 (m, CHMe), 2.66 (m, Hsyn
of CH2), 2.35 (m, Hanti of CH2), 2.27 (s, C6H4Me), 1.14 (m,
CHMe), 1.01 (t, 3J HH ) 7.1 Hz, CH2Me); 13C{1H} NMR (CDCl3)
δ 156.3 (t, J PC ) 8 Hz, J PtC ) 120 Hz, CCH2), 145-126 (m, Ph,
C6H4), 50.1 (d, J PC ) 52 Hz, J PtC ) 230 Hz, CHMe), 44.1 (s,
NCH2), 36.2 (d, J PC ) 47 Hz, J PtC ) 186 Hz, CCH2), 21.2 (s,
C6H4Me), 16.6 (d, J PC ) 6 Hz, J PtC ) 48 Hz, CHMe), 13.4 (br
vacuum: Yield 0.251
g
(92%) of [(PPh3)2Pd(η3-CH2C-
1
(NEt2)CHPh)]BF4 (6a (BF4)); H NMR (CD2Cl2) δ 7.7-6.9 (m,
Ph), 4.98 (m, CHPh), 3.16 (m, NCH2), 2.80 (m, CH2), 1.09 (t,
Me); 13C{1H} NMR (CD2Cl2) δ 151.2 (t, J PC ) 5 Hz, CCH2),
138-127 (m, Ph), 71.1 (d, J PC ) 44 Hz, CHPh), 47.8 (d, J PC
)
40 Hz, CCH2), 44.6 (s, NCH2), 13.4 (s, Me); 31P{1H} NMR (CD2-
Cl2) δ 24.4 (d, J PP ) 32 Hz), 23.5 (d, J PP ) 32 Hz); MS (FAB),
106Pd isotope, m/ z 818 (M+).
s, CH2Me); 31P{1H} NMR (CDCl3) δ 18.2 (d, J PP ) 7 Hz, J PtP
3420 Hz), 15.4 (d, J PP ) 7 Hz, J PtP ) 2910 Hz).
)
6a was also prepared and isolated as 6a (OTs) either from
2a(OTs) and Et2NH or from Pd2(dba)3‚CHCl3, PPh3, PhCtCCH2-
OS(O)2C6H4Me-p, and Et2NH. The procedures were similar
to those already described. The yields were ca. 92 and 72%,
respectively. Spectroscopic properties of the product agreed
with those of 6a (BF4). Anal. Calcd for C56H55NO3P2PdS: C,
67.91; H, 5.60; N, 1.41. Found: C, 67.34; H, 5.85; N, 1.52.
R ea ct ion of [(P P h 3)2P d (η3-CH2CCMe)]+ (2b ) w it h
Et2NH. By using procedures strictly analogous to those for
the preparation of 6a , [(PPh3)2)Pd(η3-CH2C(NEt2)CHMe)]+
(6b) was isolated as the beige 6b(BF4) and the white 6b(OTs)
in similar yields. 6b(BF4): 1NMR (CD2Cl2) δ 7.6-7.0 (m, Ph),
3.35 (m, CHMe), 3.02 (m, NCH2), 2.80 (m, CCH2), 1.16 (m,
CHMe), 0.97 (t, CH2Me); 13C{1H} NMR (CD2Cl2) δ 152.3 (t, J PC
) 5 Hz, CCH2), 134-128 (m, Ph), 62.7 (d, J PC ) 46 Hz, CHMe),
45.9 (d, J PC ) 41 Hz, CCH2), 44.0 (s, NCH2), 16.3 (CHMe), 13.3
(CH2Me); 31P{1H} NMR (CD2Cl2) δ 24.4 (d, J PP ) 29 Hz), 22.6
(d, J PP ) 29 Hz); MS (FAB), 106Pd isotope, m/z 756 (M+).
6b(OTs): Anal. Calcd for C51H53NO3P2PdS: C, 65.98; H, 5.75;
N, 1.51. Found: C, 65.74; H, 5.80; N, 1.49.
Cr ysta llogr a p h ic An a lysis of [(P P h 3)2P t(η3-CH2CCP h )]-
O3SCF 3‚CH 2Cl2 (1a (OTf)‚CH 2Cl2) a n d [(P P h 3)2P d (η3-
CH2CCP h )]BF 4 (2a (BF 4)). Crystals of 1a (OTf)‚CH2Cl2, pale
gold rods, were grown from CH2Cl2/hexane, and those of
2a (BF4), pale yellow rods, from CH2Cl2/diethyl ether. Both
data sets were measured on a Rigaku AFC5S diffractometer
with graphite-monochromated Mo KR radiation. The unit cell
constants were obtained by a least-squares fit of the diffrac-
tometer setting angles using 25 reflections in the 2θ range 24
Reaction of [(P P h 3)2P d(η3-CH2CCP h )]+ (2a) with MeOH
a n d Ba se. A solution of NaOMe (0.002 g, 0.037 mmol) in
MeOH (1 mL, 27 mmol) was added to 2a (BF4) (0.250 g, 0.300
mmol) dissolved in 10 mL of CH2Cl2, and the resulting mixture
was stirred at room temperature for 30 min. The volatiles
were removed under reduced pressure, the yellow residue was
dissolved in a minimum amount of CH2Cl2, and 1 mL of THF
was added. The solution was filtered through Celite and
treated with 5 mL of Et2O to induce the precipitation of a pale
yellow solid. The product [(PPh3)2Pd(η3-CH2C(OMe)CHPh)]-
BF4 (5a (BF4)) was collected on a filter frit, washed with 5 mL
of Et2O, and dried under vacuum: Yield 0.240 g (92%); 1H
NMR (CD2Cl2) δ 7.6-6.6 (m, Ph), 4.51 (m, CHPh), 3.55 (OMe),
3.20 (m, CH2); 13C{1H} NMR (CD2Cl2) δ 151.2 (t, J PC ) 5 Hz,
CCH2), 133-127 (m, Ph), 81.1 (dd, J PC ) 26, 10 Hz, CHPh),
58.9 (dd, J PC ) 24, 9 Hz, CH2), 56.4 (s, OMe); 31P{1H} NMR
(CD2Cl2) δ 25.8 (br); MS (FAB), 106Pd isotope, m/ z 777 (M+).
When this reaction was conducted without added base
(NaOMe or NEt3 (1 drop)), no formation of 5a (BF4) was
observed by 31P{1H} NMR spectroscopy.
5a was also obtained, in comparable yield, as the pale yellow
5a (OTs), by reaction of 2a (OTs) with MeOH and NaOMe under
similar conditions and with a similar workup. Alternatively,
5a (OTs) can be prepared by treatment of a solution of Pd2-
(dba)3‚CHCl3 (0.225 g, 0.435 mmol of Pd) and PPh3 (0.228 g,
0.870 mmol) in 20 mL of CH2Cl2 with PhCtCCH2OS(O)2C6H4-
Me-p (0.125 g, 0.436 mmol), followed by addition of NaOMe

168 Organometallics, Vol. 15, No. 1, 1996
Baize et al.
Ta ble 1. Cr ysta l Da ta a n d Da ta Collection a n d
Refin em en t for 1a (OTf)‚CH2Cl2 a n d 2a (BF 4)
so was restricted to isotropic refinement too. Hydrogen atoms
were included in the model as fixed contributions based on
calculated positions at C-H ) 0.98 Å and B(H) ) 1.2Beq-
(attached carbon atom). The two hydrogen atoms bonded to
C(1) were refined isotropically. The final refinement cycle was
based on the 5797 intensities with I > 3σ(I) and 484 variables
and resulted in agreement factors of R ) 0.047 and Rw ) 0.056.
The final difference electron density map contains two large
peaks of 1.86 and 1.45 e/Å3 in the immediate vicinity of Cl(2).
The next largest peak is 0.98 e/Å3, and the minimum peak is
-1.08 e/Å3. Neutral atom scattering factors are used and
include terms for anomalous scattering.31
Crystal Data
cmpd
chem formula
fw
1a (OTf)‚CH2Cl2
2a (BF4)
C45H37BF4P2Pd
832.90
C
47H39Cl2F3O3P2PtS
1068.82
cryst syst
space group
a, Å
b, Å
c, Å
R, deg
â, deg
γ, deg
V, Å3
monoclinic
P21/n
10.678(3)
19.633(4)
21.428(2)
triclinic
P1h
10.547(1)
12.031(2)
16.125(1)
101.570(7)
105.493(8)
92.355(7)
1922.1(3)
2
92.68(1)
The structure of 2a (BF4) was solved for the positions of the
Pd and two P atoms by the Patterson method using SHELXS-
8632 in P1h. Phasing on these three atoms revealed the rest of
the complex on an electron density map. However, the position
4487(1)
4
1.58
34.44
Z
D
calcd, g cm-3
1.44
6.07
µ(Mo KR), cm-1
-
of the BF4 anion was not evident at this point. Full-matrix
cryst size, mm
0.17 × 0.21 × 0.38
0.15 × 0.19 × 0.19
least-squares refinements on F2 were performed in SHELXL-
2
93;33 the function minimized was ∑w(Fo - Fc2)2. The BF4
Data Collection and Refinement
temp, °C
ambient
ambient
group is disordered, and it was modeled in terms of two
orientations sharing a common boron atom. The set of fluorine
atoms belonging to one orientation is labeled as F(1), F(2), F(3),
and F(4), while the set belonging to the second orientation is
labeled F(1A), F(2A), F(3A), and F(4A). The occupancy factor
for F(1) was refined, and the others were constrained accord-
ingly. Its final value was 0.54(1). The fluorines were kept
isotropic while the boron was refined anisotropically. The
hydrogen atoms for the phenyl rings are included in the struc-
ture using a riding model with C-H ) 0.98 Å and U(H) )
1.2Ueq(attached carbon atom). The two hydrogen atoms
bonded to C(1) were located on a difference electron density
map and refined isotropically. The final refinement cycle was
based on all the 8881 unique intensities and 483 variables and
resulted in agreement indices of R(F) ) 0.102 and Rw(F2) )
radiation
Mo KR with graphite monochromator
transm factors
2θ limits, deg
scan speed, deg
min-1 (in ω)
scan type
scan range,
deg (in ω)
0.75-1.0
4-55
0.890-0.920
4-55
4 with up to 3
rescans
4 with up to 3
rescans
ω
ω-2θ
1.30 + 0.35 tan θ
1.20 + 0.35 tan θ
data collcd
unique data
unique data used
in refinement
final no. of
variables
+h,+k,(l
10 613
5797a
+h,(k,(l
8881
8881
484
483
R(F)b
0.047
0.056
0.102
Rw(F)c
2
0.129. For the subset of intensities with Fo > 2σ(Fo2) (6016
Rw(F2)d
0.129
1.02
error in obsn of
unit wt, e
1.79
reflections) the R(F) value is 0.048. The final difference elec-
tron density map contains maximum and minimum peak
heights of 0.75 and -0.51 e/Å3. Neutral atom scattering fac-
tors were used and included terms for anomalous dispersion.34
Final positional and equivalent thermal parameters for
1a (OTf)‚CH2Cl2 and 2a (BF4) are given in Tables 2 and 3,
respectively. Other data are provided as Supporting Informa-
tion; see the paragraph at the end of this paper.
With Fo > 3σ(Fo2). R(F) ) ∑||Fo| - |Fc||/∑|Fo|. c Rw(F) )
a
2
b
[∑w(|Fo| - |Fc|)2/∑wFo
]
1/2 with w ) 1/σ2(Fo). Rw(F2) ) [∑w(Fo
-
2
d
2
Fc2)2/∑wFo
]
1/2, where w ) 1/[σ2(Fo2) + (0.0521P)2 + 1.5355P] and
4
P ) 1/3(maximum of (0 or Fo2)) + 2/3(Fc)2.
to 30° for 1a (OTf)‚CH2Cl2 and 25 reflections in the 2θ range
21 to 30° for 2a (BF4). The crystal data are given in Table 1.
Six standard reflections were measured after every 150
reflections during data collection and indicated some crystal
decay for both structures. On the average the standards
decreased in intensity by 10.9% for 1a (OTf)‚CH2Cl2 and 3.3%
for 2a (BF4). Data reduction was done with the TEXSAN
package,27 and a linear decay correction was applied to both
data sets. The data set for 1a (OTf)‚CH2Cl2 was corrected for
absorption by the ψ scan method,28 and an analytical absorp-
tion correction was applied to the data set for 2a (BF4).29
For 1a (OTf)‚CH2Cl2, the Pt atom was located by the Patter-
son method. The rest of the structure was elucidated by means
of the DIRDIF procedure30 and standard Fourier methods.
There is a solvent molecule of CH2Cl2 in the asymmetric unit.
Full-matrix least-squares refinements were performed in
TEXSAN;27 the function minimized was ∑w(|Fo| - |Fc|)2 with
w ) 1/σ2(Fo). The triflate group was not well behaved. It was
necessary to treat the CF3 half as a rigid group, with each atom
having its own isotropic thermal parameter. In the SO3
portion, the oxygen atoms were refined isotropically and
acquired large B values, which is an indication of disorder.
The CH2Cl2 molecule also seemed to suffer from disorder and
Resu lts a n d Discu ssion
Syn t h esis of [(P P h 3)2M(η3-CH2CCR )]+ (1, M )
P t; 2, M ) P d ). Cationic platinum and palladium η3-
propargyl/allenyl complexes of general formula
[(PPh3)2M(η3-CH2CCR)]+ have been prepared by several
methods. Thus, complex 1a results upon treatment of
trans-(PPh3)2Pt(Br)(η1-CH2CtCPh) with 1 equiv of AgO3-
SCF3 in THF at room temperature (eq 1) and was
(31) Scattering factors for the non-hydrogen atoms, including terms
for anomalous dispersion, are from: International Tables for X-ray
Crystallography; Kynoch Press: Birmingham, England, 1974; Vol. IV,
pp 71, 148. The scattering factor for the hydrogen atom is from:
Stewart, R. F.; Davidson, E. R.; Simpson, W. T. J . Chem. Phys. 1965,
42, 3175.
(27) TEXSAN, Single Crystal Structure Analysis Software, Version
5.0, Molecular Structure Corp., The Woodlands, TX 77381, 1989.
(28) North, A. C. T.; Phillips, D. C.; Mathews, F. S. Acta Crystallogr.
1968, A24, 351.
(29) De Meulenaer, J .; Tompa, H. Acta Crystallogr. 1965, 19, 1014.
(30) Parthasarathi, V.; Beurskens, P. T.; Slot, H. J . B. Acta Crys-
tallogr. 1983, A39, 860.
(32) Sheldrick, G. M. Acta Crystallogr. 1990, A46, 467.
(33) Sheldrick, G. M. SHELXL-93, Program for the Refinement of
Crystal Structures; Universita¨t Go¨ttingen: Go¨ttingen, Germany, 1993.
(34) International Tables for Crystallography; Kluwer Academic
Publishers: Dordrecht, The Netherlands, 1992; Vol. C.

Pt and Pd η3-Propargyl/ Allenyl Complexes
Organometallics, Vol. 15, No. 1, 1996 169
Ta ble 2. P osition a l a n d Equ iva len t Isotr op ic
An alternative preparation of 1a entails acid cleavage
of a phenylpropargyl ether complex of platinum(0). The
reaction presented in eq 2 also affords 1a in excellent
Th er m a l P a r a m eter s for 1a (OTf)‚CH2Cl2
a
atom
x
y
z
Beq or B, Å2
Pt
P(1)
P(2)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
C(9)
C(10)
C(11)
C(12)
C(13)
C(14)
C(15)
C(16)
C(17)
C(18)
C(19)
0.23893(3)
0.2528(2)
0.1605(2)
0.228(1)
0.276(1)
0.308(1)
0.360(1)
0.488(1)
0.534(1)
0.457(2)
0.335(2)
0.281(1)
0.4136(9)
0.446(1)
0.565(1)
0.655(1)
0.626(1)
0.508(1)
0.1740(9)
0.211(1)
0.142(1)
0.032(1)
0.05495(2)
-0.0546(1)
0.0349(1)
0.1655(5)
0.1493(5)
0.1082(5)
0.0967(4)
0.0986(5)
0.0914(6)
0.0845(7)
0.0816(8)
0.0885(6)
-0.0830(5)
-0.1512(5)
-0.1720(7)
-0.1222(8)
-0.0538(6)
-0.0351(5)
-0.0597(5)
-0.1054(5)
-0.1112(6)
-0.0734(7)
-0.0278(6)
-0.0212(5)
-0.1239(4)
-0.1457(5)
-0.1958(7)
-0.2257(6)
-0.2060(6)
-0.1551(5)
-0.0115(4)
-0.0237(6)
-0.0592(6)
-0.0815(6)
-0.0678(6)
-0.0325(5)
-0.0063(5)
-0.0618(5)
-0.0894(7)
-0.0640(9)
-0.0087(8)
0.0205(6)
0.1122(5)
0.1463(6)
0.2047(7)
0.2299(7)
0.1963(8)
0.1375(6)
0.1615(2)
0.1926(8)
0.162(1)
0.23600(2)
0.2733(1)
0.1378(1)
0.2246(5)
0.2844(5)
0.3252(5)
0.3885(5)
0.4011(5)
0.4617(7)
0.5098(6)
0.4977(6)
0.4371(5)
0.2901(4)
0.2985(5)
0.3151(6)
0.3242(5)
0.3170(5)
0.2983(4)
0.3463(4)
0.3940(5)
0.4463(5)
0.4521(5)
0.4053(5)
0.3530(5)
0.2282(4)
0.2392(5)
0.2024(6)
0.1551(7)
0.1434(5)
0.1803(5)
0.0871(4)
0.0252(4)
-0.0137(5)
0.0083(6)
0.0699(6)
0.1081(5)
0.1400(4)
0.1038(5)
0.1115(6)
0.1552(8)
0.1906(6)
0.1844(5)
0.0918(4)
0.0690(5)
0.0338(6)
0.0230(7)
0.0445(8)
0.0802(6)
0.3223(3)
0.3118(8)
0.2715(9)
0.3479(9)
0.1698(2)
0.1105(4)
0.169(1)
3.21(1)
3.4(1)
3.4(1)
5.1(6)
5.3(5)
4.6(5)
4.4(5)
5.2(6)
6.4(7)
7.1(8)
8.4(9)
6.3(7)
3.7(4)
5.6(6)
7.3(8)
6.9(8)
5.6(6)
4.2(5)
3.9(4)
5.0(5)
6.5(7)
6.4(7)
6.0(6)
4.8(5)
3.7(4)
5.5(6)
7.6(8)
7.5(8)
7.2(7)
5.4(6)
3.5(4)
5.0(5)
6.0(6)
6.2(7)
6.4(7)
4.5(5)
3.9(4)
4.7(5)
6.8(7)
8(1)
yield and is simple to carry out. The precursor (PPh3)2-
Pt(η2-PhCtCCH2OMe) can be obtained by treatment of
(PPh3)2Pt(η2-C2H4) with PhCtCCH2OMe.
In an attempt to develop a “one-pot” synthesis of 1
from a non-propargyl or -allenyl compound of platinum,
(PPh3)2Pt(η2-C2H4) was treated with each of PhCtCCH2-
OS(O)2C6H4Me-p and MeCtCCH2OS(O)2C6H4Me-p. It
was thought that the presence of a relatively poor
coordinating ligand, tosylate (OTs), may lead to the
formation of 1 by oxidative addition of RCtCCH2OS-
(O)2C6H4Me-p at the platinum center (eq 3). Examina-
C(20) -0.006(1)
C(21)
C(22)
C(23)
C(24)
C(25)
C(26)
C(27)
C(28)
C(29)
C(30)
C(31)
C(32)
C(33)
C(34)
0.066(1)
0.180(1)
0.060(1)
0.003(1)
0.064(2)
0.182(2)
0.242(1)
0.2603(9)
0.222(1)
0.299(1)
0.414(1)
0.454(1)
0.378(1)
0.0087(9)
tion of solutions of (PPh3)2Pt(η2-C2H4) and RCtCCH2-
OS(O)2C6H4Me-p in CH2Cl2 by NMR spectroscopy
revealed that the expected η3-propargyl/allenyl product
had indeed formed. This was further corroborated by
addition to these solutions of MeOH or Et2NH, which
resulted in the formation of the appropriate η3-allyl
complexes with the OMe or NEt2 substituents at C(2)
(3 or 4, respectively; vide infra). However, attempts at
isolation of the η3-propargyl/allenyl complexes 1a (OTs)
and 1b(OTs) invariably led to the formation of unidenti-
fied decomposition products. It would appear that the
decomposition is caused by the presence of the tosylate
counterion, but we do not know whether this anion
triggers it by coordinating to platinum or to the η3-
propargyl/allenyl ligand or by reacting in some other
manner.
Finally, a rather unusual method of synthesis of
methyl-substituted derivatives of 1, [(PPh3)2Pt(η3-
MeCHCCR)]+, was recently reported by Stang and co-
workers.9 These complexes were obtained by reaction
of (PPh3)2Pt(η2-C2H4) with [RCtCIPh]O3SCF3 where R
) t-Bu, n-Bu, SiMe3, or Me (eq 4). Generally, trans-
(PPh3)2Pt(OS(O)2CF3)(CtCR) was a coproduct.
C(35) -0.032(1)
C(36) -0.148(1)
C(37) -0.224(1)
C(38) -0.188(1)
C(39) -0.071(1)
C(40)
C(41)
C(42)
C(43)
6.8(7)
5.2(6)
4.1(5)
6.0(6)
8(1)
0.130(1)
0.232(1)
0.215(2)
0.095(2)
10(1)
9(1)
C(44) -0.002(2)
C(45)
S
0.012(1)
0.8395(5)
0.724(2)
0.923(2)
0.837(2)
0.5484(5)
0.5945(8)
0.635(2)
0.922(1)
0.937(1)
0.847(1)
1.031(1)
6.6(7)
11.1(3)
18.4(6)*
20.8(7)*
20.0(6)*
12.1(1)*
20.3(3)*
13.5(6)*
18.7(9)**
20.0(5)**
28.3(8)**
26.2(7)**
O(1)
O(2)
O(3)
Cl(1)
Cl(2)
C(47)
C(46)
F(1)
F(2)
F(3)
0.101(1)
0.1172(3)
0.2419(4)
0.191(1)
0.2191(5)
0.2786(7)
0.225(1)
0.3728(5)
0.3465(6)
0.4189(8)
0.3943(8)
0.1962(7)
a
The form of the equivalent isotropic displacement parameter
is Beq ) (8π2/3)∑i∑jUija*ia*ja i‚a j. Asterisks designate B values for
atoms refined isotropically. Double asterisks designate B values
for atoms refined as part of a rigid group.
isolated as the triflate salt 1a (OTf) in 96% yield.
Similarly, 1c(BF4) was obtained from trans-(PPh3)2PtBr-
(η1-CHdCdCH2) and AgBF4 in CH2Cl2 at -30 °C by
Chen and co-workers.8 This methodology has the
advantage of simplicity and high yield of the product;
however, it does require the availability of the appropri-
ate halogeno-η1-propargyl or -η1-allenyl complex of
platinum(II) as the immediate precursor. The latter are
generally accessible from platinum(0) phosphine com-
plexes and propargyl or allenyl halides.35
The palladium complexes 2a ,b were synthesized
similarly to the platinum complexes 1a ,c10,11 (cf. eq 1).
(35) Wouters, J . M. A.; Klein, R. A.; Elsevier, C. J .; Ha¨ming, L.;
Stam, C. H. Organometallics 1994, 13, 4586.

170 Organometallics, Vol. 15, No. 1, 1996
Baize et al.
Ta ble 3. P osition a l a n d Equ iva len t Isotr op ic
Disp la cem en t P a r a m eter s for 2a (BF 4)
a
atom
x
y
z
Ueq
,
Å2
Pd
P(1)
P(2)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
C(9)
0.20997(3)
0.09152(10)
0.06406(10)
0.3642(5)
0.4101(4)
0.4019(4)
0.4558(5)
0.5452(5)
0.6004(6)
0.5665(7)
0.4768(7)
0.4229(6)
0.2007(4)
0.2639(4)
0.3466(5)
0.3694(5)
0.3106(5)
0.2255(4)
0.0476(4)
0.0936(5)
0.0628(6)
0.35147(3)
0.40833(9)
0.21964(9)
0.3271(5)
0.4097(4)
0.4700(4)
0.5462(4)
0.5084(5)
0.5812(7)
0.6894(7)
0.7286(6)
0.6570(5)
0.4048(4)
0.3077(4)
0.2965(5)
0.3854(5)
0.4842(5)
0.4952(4)
0.5541(3)
0.6215(4)
0.7337(4)
0.7769(4)
0.7088(4)
0.5983(4)
0.3319(4)
0.2804(4)
0.2246(5)
0.2212(5)
0.2731(5)
0.3292(5)
0.2844(4)
0.2205(4)
0.2729(5)
0.3869(5)
0.4503(5)
0.4004(4)
0.1139(3)
0.0755(4)
-0.0024(4)
-0.0404(4)
-0.0030(5)
0.0748(4)
0.1373(4)
0.0501(4)
0.0005(5)
0.0366(6)
0.1205(6)
0.1725(5)
0.0664(10)
-0.0218(11)
0.0487(8)
0.1678(9)
0.0814(12)
-0.0220(12)
0.1533(13)
0.076(2)
0.32506(2) 0.0316(1)
0.19872(7) 0.0324(2)
0.34484(7) 0.0335(2)
0.4370(4)
0.4005(3)
0.3462(3)
0.3028(3)
0.2565(3)
0.2166(4)
0.2202(4)
0.2651(5)
0.3080(4)
0.1279(3)
0.1133(3)
0.0588(3)
0.0210(3)
0.0371(3)
0.0898(3)
0.2225(3)
0.3072(3)
0.3242(4)
0.2570(4)
0.1743(4)
0.1566(3)
0.1245(3)
0.0379(3)
-0.0153(4)
0.0178(4)
0.1037(4)
0.1565(3)
0.3875(3)
0.4129(3)
0.4424(4)
0.4501(3)
0.4264(3)
0.3952(3)
0.2439(3)
0.1906(3)
0.1123(3)
0.0849(4)
0.1362(4)
0.2167(3)
0.4250(3)
0.4004(4)
0.4640(4)
0.5513(4)
0.5761(4)
0.5134(3)
0.2243(7)
0.2152(9)
0.1512(6)
0.2242(7)
0.3047(9)
0.2176(9)
0.052(1)
0.047(1)
0.046(1)
0.050(1)
0.061(1)
0.079(2)
0.085(2)
0.087(2)
0.068(2)
0.035(1)
0.043(1)
0.051(1)
0.054(1)
0.056(1)
0.044(1)
0.035(1)
0.045(1)
0.059(1)
0.060(1)
0.058(1)
0.047(1)
0.036(1)
0.052(1)
0.067(2)
0.068(2)
0.066(2)
0.054(1)
0.038(1)
0.052(1)
0.062(2)
0.059(1)
0.055(1)
0.043(1)
0.036(1)
0.046(1)
0.058(1)
0.066(2)
0.064(2)
0.051(1)
0.042(1)
0.058(1)
0.070(2)
0.076(2)
0.073(2)
0.059(1)
0.094(3)
0.138(4)*
0.113(4)*
0.131(4)*
0.166(5)*
0.152(6)**
method afforded the η3-propargyl/allenyl complexes in
81-83% yield. It is noteworthy that the use of
RCtCCH2OS(O)2C6H4Me-p with Pd2(dba)3‚CHCl3 and
PPH3 gives the tosylate salts of 2 that are stable toward
isolation. In contrast, as mentioned earlier, use of
RCtCCH2OS(O)2C6H4Me-p with (PPh3)2Pt(η2-C2H4)
yields the corresponding platinum complexes that de-
compose during workup. The difference in behavior
may be a result of the observed greater tendency of 1
than of 2 to undergo reaction with nucleophilic reagents.
This aspect of the relative chemistry of 1 and 2 will be
considered later in the paper.
Sp ectr oscop ic P r op er ties of P la tin u m a n d P a l-
la d iu m η3-P r op a r gyl/Allen yl Com p lexes. The pal-
ladium complexes 2a ,b are pale yellow solids when
isolated as 2(BF4) and off-white solids when obtained
as the tosylates. The platinum complex 1a is a beige
to pale yellow solid with the various counterions used.
All are stable to air in the solid. 2a ,b do not appear to
be affected by moisture, whereas 1a slowly reacts with
water in the air.37
C(10)
C(11)
C(12)
C(13)
C(14)
C(15)
C(16)
C(17)
C(18)
C(19) -0.0167(6)
C(20) -0.0650(5)
C(21) -0.0344(5)
C(22) -0.0639(4)
C(23) -0.0783(5)
C(24) -0.1994(6)
C(25) -0.3065(5)
C(26) -0.2933(5)
C(27) -0.1731(5)
C(28) -0.0646(4)
C(29) -0.1542(5)
C(30) -0.2543(5)
C(31) -0.2615(5)
C(32) -0.1723(5)
C(33) -0.0737(4)
C(34) -0.0130(4)
C(35)
C(36)
C(37) -0.1167(7)
C(38) -0.1979(6)
C(39) -0.1464(5)
C(40)
C(41)
C(42)
C(43)
C(44)
C(45)
B
NMR spectroscopic properties of 1 and 2 (cf. Experi-
mental Section) serve to characterize these products as
η3-propargyl/allenyl complexes and rule out possible η1-
propargyl and -allenyl modes of attachment of the
organic ligand to the metal. Thus, the 1H NMR spectra
of 1a and 2a ,b show that the CH2 protons are equivalent
and coupled differently to the two phosphorus nuclei.
The different coupling is in agreement with the two
PPh3 ligands appearing inequivalent in the 31P{1H}
NMR spectra. The chemical shift of the CH2 protons is
comparable to that for metal η1-allenyl complexes but
is appreciably downfield (0.6-1.9 ppm) from that for
analogous metal η1-propargyl complexes.1 In the 13C-
{H} NMR spectra, signals of the η3-propargyl/allenyl
ligand are observed at δ 105.4-102.1, 97.3-91.2, and
53.1-48.3. All of them show coupling to the phosphorus
nuclei, with additional coupling to 195Pt for 1a . Those
of the terminal carbon atoms CH2 at δ 53.1-48.3 and
CR at δ 105.4-102.1 display much stronger coupling
to one phosphorus (37-47 Hz) than to the other (<1.5
Hz), in agreement with a distorted square-planar dis-
position of the CH2, CR, and two P atoms around the
metal (vide infra). The central carbon atom is only
weakly coupled to the phosphorus nuclei. The reso-
nance of the CH2 carbon atom for 1 and 2 at δ 53.1-
48.3 appears downfield from that for metal η1-propargyl
complexes at δ e 8, whereas the resonance of the central
carbon atom of 1 and 2 at δ 97.3-91.2 occurs much
farther upfield than that for metal η1-allenyl complexes
at δ g 194.1,14,35,38 Furthermore, for 1a , each of the CH2
and CR carbon atoms is quite strongly coupled to 195Pt
(J PtC ) 126 and 93 Hz, respectively), as expected for an
η3 mode of attachment of the propargyl/allenyl ligand.
0.0665(5)
0.0149(6)
0.1436(4)
0.2169(5)
0.2974(6)
0.3005(6)
0.2249(6)
0.1487(5)
0.4629(9)
0.5454(12)
0.3606(10)
0.5370(10)
0.4418(13)
0.3584(14)
0.4142(14)
0.452(2)
F(1)
F(2)
F(3)
F(4)
F(1A)
F(2A)
F(3A)
F(4A)
0.2711(10) 0.153(6)**
0.1410(13) 0.201(8)**
0.5710(11)
0.0222(10)
0.2588(8)
0.097(3)**
a
The form of the equivalent isotropic displacement param-
1/3∑i∑jUija*ia*ja i‚a j. Asterisks designate isotropic
eter is Ueq
)
refinement with occupancy factor of 0.54(1). Double asterisks
designate isotropic refinement with occupancy factor of
0.46(1).
Treatment of the isomeric mixtures of trans-(PPh3)2-
PdBr(η1-CH2CtCR) and trans-(PPh3)2PdBr(η1-C(R))
CdCH2) (R ) Ph, Me), prepared by the general method
of Boersma,36 with AgBF4 in CH2Cl2 solution led to the
isolation of 2a ,b in 90-92% yield. 2a ,b were also
prepared by addition of RCtCCH2OS(O)2C6H4Me-p to
a solution of Pd2(dba)3‚CHCl3 and PPh3 in CH2Cl2
followed by stirring at room temperature (eq 5). This
(37) Baize, M. W.; Furilla, J . L.; Wojcicki, A. Inorg. Chim. Acta 1994,
223, 1.
(36) Elsevier, C. J .; Kleijn, H.; Boersma, J .; Vermeer, P. Organo-
metallics 1986, 5, 716.
(38) Shuchart, C. E.; Willis, R. R.; Wojcicki, A. J . Organomet. Chem.
1992, 424, 185.

Pt and Pd η3-Propargyl/ Allenyl Complexes
Organometallics, Vol. 15, No. 1, 1996 171
Rotation of the cationic complex by 90° about the
M-C(2) axis generates a structure which is shown in
Figure 2 for 2a . The atoms C(1), C(2), C(3), Pd (or Pt,
for 1a ), P(1), and P(2) essentially lie in one plane, as
evidenced by the dihedral angles listed in Table 4. (The
respective displacements of the atoms M, P(1), and P(2)
from the C(1)C(2)C(3) plane are -0.0362, 0.1129, and
-0.0514 Å for 1a and -0.0908, -0.0742, and -0.1788
Å for 2a .) The coordination environments of C(1), C(3),
P(1), and P(2) around the metal center in 1a and 2a
are thus planar but appreciably distorted from square-
planar because of the differences in the bond angles as
depicted in Figure 3A,B. The observed distortion is
similar to that recently reported for the η3-trimethyl-
enemethane complex (PPh3)2Pt(η3-CH2C(C(CO2Me)2)-
CHPh)41 (Figure 3C). In contrast, the platinacyclobu-
tane complex (PEt3)2Pt(η2-CH2CMe2CH2) shows a much
more regular square-planar coordination environment42
(Figure 3D).
Rea ction s of P la tin u m a n d P a lla d iu m η3-P r op -
a r gyl/Allen yl Com p lexes. The platinum complexes
1a ,b react with nucleophilic reagents of the type NuH
(NuH ) MeOH, Et2NH) to afford the corresponding η3-
allyl complexes 3a ,b and 4a ,b, respectively, with the
nucleophile Nu- adding to the central carbon atom (eq
6). The palladium complexes 2a ,b react similarly with
Et2NH to give 6a ,b, but they add MeOH only in the
presence of trace amounts of OMe- or NEt3 to yield
5a ,b.
F igu r e 1. ORTEP drawing of 1a in 1a (OTf)‚CH2Cl2
showing the atom-numbering scheme. Only the ipso car-
bon atoms have been numbered for the phenyl rings. The
non-hydrogen atoms are represented by 50% probability
thermal ellipsoids. The CH2 hydrogen atoms are drawn
with artificial radii, and the phenyl hydrogen atoms are
omitted.
In the proton-coupled 13C NMR spectrum of 1a , the
1
coupling constant J CH ) 170 Hz for the CH2 moiety
shows sp2 hybridization at carbon,39 also consistent with
this type of ligation. In contrast, the corresponding 1J CH
) 140 Hz for trans-(PPh3)2PtBr(η1-CH2CtCPh) indi-
cates sp3 hybridization.39
Str u ctu r a l Ch a r a cter iza tion of [(P P h 3)2M(η3-
CH2CCP h )]+ (1a , M ) P t; 2a , M ) P d ). The structure
of the cationic platinum complex 1a (in 1a (OTf)‚CH2-
Cl2) is shown in Figure 1; that of the palladium analogue
2a (in 2a (BF4)) is virtually identical and was given the
same atom-numbering scheme. Selected bond dis-
tances, bond angles, and dihedral angles for both
complexes are presented in Table 4.
The addition of Et2NH to the η3-propargyl/allenyl
ligand of 1a ,b proceeds stereospecifically to give η3-allyl
products in which the groups R and NEt2 are anti (III).
The CH2CCPh ligand is bent and attached to the
metal in an η3 mode. The degree of bending (152.2(9)°
for 1a , 154.7(5)° for 2a ) is comparable to that found in
other transition-metal η3-propargyl/allenyl and related
η3-butenynyl complexes.2,3,6,9 Interestingly, the value
of this angle is approximately halfway between that for
an unperturbed allenyl or propargyl fragment (180°) and
the η3-allyl ligand in metal complexes (120°).40 For both
cations 1a and 2a , the M-C bond distances follow the
order M-C(2) e M-C(1) < M-C(3). The M-C(1)
distance is essentially identical for the two complexes,
as is also the M-C(2) distance. However, the M-C(3)
distance is somewhat longer for 2a than for 1a . These
relative bond distances are consistent with the angle
C(1)-C(2)-C(3) being slightly more obtuse for the Pd
complex compared to the Pt complex. The C(1)-C(2)
and C(2)-C(3) bond lengths are respectively 1.395(14)
and 1.227(13) Å for 1a and 1.385(7) and 1.233(7) Å for
2a . They indicate substantial contributions of both η3-
allenyl and η3-propargyl resonance structures to the
bonding description of these complexes.
This orientation has been determined with the aid of
the 1H NMR spectra. The spectra show three equal-
intensity η3-allyl proton signals at δ 4.38-2.92, 2.66-
2.62, and 2.35-2.33, which are assigned respectively to
CHR and the inequivalent protons of CH2. Selective
proton decoupling experiments for 4a showed that the
hydrogens resonating at δ 4.38 and 2.62 are weakly
coupled. Such small long-range coupling (4J HH)sthe so-
called W-effectsis known to occur between syn protons
in metal η3-allyl complexes.43 The similar appearance
of the three resonances in the spectra of 4a ,b (cf.
Experimental Section) indicates that these products
have the same orientation of R and NEt2.
(39) Cooper, J . W. Spectroscopic Techniques for Organic Chemists;
Wiley-Interscience: New York, 1980; p 87.
(40) Hartley, R. F. In Comprehensive Organometallic Chemistry;
Wilkinson, G., Stone, F. G. A., Abel, E. W., eds.; Pergamon: Oxford,
U.K., 1982; Chapter 39.
(41) Plantevin, V.; Blosser, P. W.; Gallucci, J . C.; Wojcicki, A.
Organometallics 1994, 13, 3651.
(42) Ibers, J . A.; DiCosimo, R.; Whitesides, G. M. Organometallics
1982, 1, 13.
(43) Feng, S. G.; Templeton, J . L. Organometallics 1992, 11, 2168.

172 Organometallics, Vol. 15, No. 1, 1996
Baize et al.
Ta ble 4. Selected Bon d Dista n ces (Å), Bon d An gles
(d eg), a n d Dih ed r a l An gles (d eg) for
1a (OTf)‚CH2Cl2 a n d 2a (BF 4)
1a (OTf)‚CH2Cl2
2a (BF4)
Bond Distances
M-P(1)
2.297(2)
2.262(2)
2.186(11)
2.150(8)
2.273(9)
1.395(14)
1.227(13)
1.46(1)
2.3342(11)
2.2913(11)
2.162(5)
2.143(4)
2.334(5)
1.385(7)
1.233(7)
1.442(7)
M-P(2)
M-C(1)
M-C(2)
M-C(3)
C(1)-C(2)
C(2)-C(3)
C(3)-C(4)
Bond Angles
P(1)-M-P(2)
C(1)-M-P(2)
C(3)-M-P(1)
C(1)-M-P(1)
C(3)-M-P(2)
C(1)-M-C(3)
C(1)-C(2)-C(3)
C(2)-C(3)-C(4)
100.16(8)
93.0(3)
97.2(3)
166.0(3)
162.6(3)
69.6(4)
152.2(9)
148(1)
103.77(4)
92.1(1)
95.0(1)
164.0(1)
161.2(1)
69.1(2)
154.7(5)
153.7(5)
Dihedral Angles
C(1)C(2)C(3), MC(1)C(3)
MC(1)C(3), MP(1)P(2)
C(1)C(2)C(3), MP(1)P(2)
1.1
4.6
3.7
2.8
2.3
2.2
In contrast, similar decoupling experiments for the
methoxy analogue of 4a , 3a , revealed the absence of
long-range coupling (4J HH) in the 1H NMR spectrum.
The three allylic proton signals of 3a ,b are also similar
in appearance but differ from those of 4a ,b. The
complexes 3a ,b are assigned structures in which the
substituents R and OMe adopt a syn orientation (IV).
This same orientation was also inferred from the 1H
NMR spectra for the groups Ph and C(CO2Me)2 in
(PPh3)2Pt(η3-CH2C(C(CO2Me)2)CHPh)7 and was later
corroborated by an X-ray diffraction analysis.41
The palladium complexes 5a ,b and 6a ,b appear to
have the same stereochemistry of the η3-allyl ligand as
their platinum counterparts, 3a ,b and 4a ,b, respec-
tively. However, a detailed analysis of their 1H NMR
spectra is complicated by the overlap of the signals of
the syn and anti CH2 protons.44
F igu r e 2. ORTEP drawing of 2a in 2a (BF4) showing the
atom-numbering scheme. Only the ipso carbon atoms have
been numbered for the phenyl rings. The non-hydrogen
atoms are represented by 50% probability thermal el-
lipsoids. The CH2 hydrogen atoms are drawn with artificial
radii, and the phenyl hydrogen atoms are omitted. The
atoms C(2) and P(2) are hidden behind C(3) and P(1),
respectively.
The 1H NMR spectra of 3 and 4 display a large
geminal coupling constant of 6.6-9.6 Hz for the CH2
2
group. This value of J HH suggests a considerable
contribution from the metallacyclic resonance form B
The different stereochemistry of the addition of MeOH
and Et2NH to the η3-propargyl/allenyl ligand of 1 is
intriguing. The addition of NEt2 anti to R suggests that
this reaction may proceed by nucleophilic attack of
Et2NH at the central carbon atom of η3-CH2CCR,
with an essentially synchronous proton transfer to the
CR carbon (Scheme 1). The source of this proton would
be either the attacking Et2NH molecule or one at-
tached to it by hydrogen-bonding. Methanol probably
also attacks the central carbon atom of 1 but may
give an uncharged methoxy-substituted metallacy-
clobutene intermediate. Protonation at metal and
transfer of the proton to the CR carbon atom away from
the OMe group would then afford the syn orientation
of OMe and R in the product. Steric effects associ-
ated with the nucleophile apparently do not influence
the stereochemistry of the product, since other alco-
hols (R′OH), including Me3CCH2OH, also give platinum
η3-allyl complexes in which the OR′ and R groups are
syn.14
to the overall bonding description of 3 and 4. The 13C-
{1H} NMR spectra of 3-6 reveal two resonances at δ
81.1-50.1 and 58.9-35.0 which show substantial cou-
pling to one phosphorus nucleus (24-52 Hz) and small,
usually indiscernible, coupling to the other. These
signals are assigned to the CHR and CH2 carbon atoms,
respectively. In addition, there is a resonance at δ
156.3-148.6, assigned to the central carbon atom, which
appears as a singlet or a narrow triplet, with weak
coupling (e8 Hz) to both phosphorus nuclei. For the
platinum complexes 3 and 4, the former two signals
show large J PtC coupling constants (up to 236 Hz), and
the latter signal shows a smaller coupling constant (up
to 123 Hz). These 13C NMR chemical shifts and
coupling constants suggest a major contribution to the
bonding of the η3-allyl resonance form A.45
(44) The other possible explanation, viz., that these protons are in-
volved in a fluxional process, appears unlikely, since the NMe2 ana-
logue of 6a shows separate signals for the syn and anti CH2 protons.
These signals do not approach coalescence with decrease in temper-
ature.
Finally, the regiochemistry of the addition of nucleo-
philic reagents to the central carbon atom of the η3-CH2-

Pt and Pd η3-Propargyl/ Allenyl Complexes
Organometallics, Vol. 15, No. 1, 1996 173
Sch em e 1
F igu r e 3. Coordination environment including the bond
angles (deg) around the metal center: A, in 1a ; B, in 2a ;
C, in the η3-trimethylenemethane complex (PPh3)2Pt(η3-
CH2C(C(CO2Me)2)CHPh); D, in the platinacyclobutane
complex (PEt3)2Pt(η2-CH2CMe2CH2). The bond angles in C
are average values.
CCR ligand merits brief comment. According to the
rules of Green, Davies, and Mingos,46 open π-polyenyl
ligands undergo attack by nucleophiles at one of the
terminal carbon atoms, unless the MLx fragment is
electron-donating. Thus, η3-allyl complexes of pal-
ladium add nucleophiles in terminal position.12 Com-
plexes 1 and 2 represent the only open π-systems where
nucleophilic addition to the organic ligand is exclusively
nonterminal.47 Recent calculations suggest that such
reactions of 1 and 2 are charge controlled,48 and that
study will be reported later together with our further
synthetic and mechanistic investigations.14
Ack n ow led gm en t. This study was supported by
The Ohio State University. Mass spectra were obtained
at The Ohio State University Chemical Instrument
Center (funded in part by National Science Foundation
Grant 79-10019). V.P. and P.W.B. thank the Lubrizol
Co. and the Procter and Gamble Co., respectively, for
graduate fellowships.
(45) (a) J olly, P. W.; Mynott, R. Adv. Organomet. Chem. 1981, 19,
257. (b) Gregg, M. R.; Powell, J .; Sawyer, J . F. J . Organomet. Chem.
1988, 352, 357.
Su p p or tin g In for m a tion Ava ila ble: Tables of hydrogen
atom positional and thermal parameters, anisotropic thermal
parameters, and bond distances and angles for complexes
1a (OTf)‚CH2Cl2 and 2a (BF4) (16 pages). Ordering information
is given on any current masthead page.
(46) Davies, S. G.; Green, M. L. H.; Mingos, D. M. P. Tetrahedron
1978, 34, 3047.
(47) However, Br-, CO, and PMe3 add to the metal in 1a ; see ref 7.
(48) Graham, J . P.; Wojcicki, A.; Bursten, B. E. Abstracts of Papers;
210th ACS National Meeting; Chicago, IL, Aug 20-24, 1995; American
Chemical Society: Washington, DC, 1995; INOR77.
OM9506678