Synthesis of mercury(II) and palladium(II) organometallic derivatives of terephthaldehyde by metalation, transmetalation, oxidation, and condensation reactions.

Article abstract of DOI:10.1021/om970583u

The organomercurials [HgCl{C₆H₃(CHO)₂-2,5}] (1) and [Hg{C₆H₃(CHO)₂-2,5}₂] (2) have been prepared by mercuriation of terephthaldehyde. Palladium complexes [PdCl{C₆H₃-(CHO)₂-2,5}(N-N)] (N-N = N,N,N′,N′-tetramethylethylenediamine (tmeda) (3) or 2,2′-bipyridine (bpy) (3′)) or trans-[PdCl{C₆H₃(CHO)₂-2,5}(PPh ₃)₂]·H₂O (4) have been obtained by reacting (Me₄N)₂[Pd₂Cl₆] or trans-[PdCl₂(PPh₃)₂], respectively, with 1 or 2. The reaction of potassium permanganate with complexes 3 and 3′ or mercurial 1 results in the selective oxidation of the 5-formyl substituent affording [PdCl{C₆H₃(CHO)-2-(CO₂H)-5}(N-N)] (N-N = tmeda (5), bpy (5′)) or, respectively, a mixture whose major component is the fully oxidized [HgCl{C₆H₃(CO₂H)₂-2,5}] (7) or a mixture of isomers [HgCl{C₆H₃(CHO)-2-(CO₂H)-5}]/[HgCl-{C ₆H₃(CO₂H)-2-(CHO)}] (8a/8b) depending on the molar ratio of the reagents. The reaction of mixtures containing 7 or 8 with trans-[PdCl₂(PPh₃)₂] give pure trans-[PdCl{C₆H₃(CO₂H) ₂-2,5}(PPh₃)₂] (9) or trans-[PdCl{C₆H₃(CHO)-2-(CO₂H)-5}(PPh ₃)₂] (10), respectively. Complexes 3 and 3′ react with amines and NaClO₄·H₂O or Tl(CF₃SO₃) to give, depending of the reaction conditions, cyclopalladated derivatives [Pd{C₆H₃(CH=NR)-2-(CH=NR)-5}(N-N)]⁺ or [Pd-{C₆H₃(CH=NR)-2-(CHO)-5}(tmeda)]⁺. The mercurial 1 reacts with hydroxylamine to give the mercuriated oxime [HgCl{C₆H₃(CH=NOH)₂-2,5}] (14), which reacts with (Me₄N)₂[Pd₂-Cl₆] to give the cyclopalladated complex [Pd{C₆H₃(CH=NOH)-2-(CH=NOH)-5}(μ-Cl]₂ (15). From 15 some derivatives have been prepared. Complex 3 reacts with NH₂OMe to give [Pd{C₆H₃(CH=NOMe)-2-(CH=NOMe)-5}(tmeda)]ClO ₄(19). Theimine C₆H₄(CH=NTo)₂-1,4(To = C₆H₄Me-4) reacts with palladium(II) acetate to give the dipalladated imine [Pd{C₆H ₂-(CH=NTo)-2-{Pd(μ-OAc)}-4-(CH=NTo)-5}(μ-OAc)]_n (20). Hydrolysis of 20 in the presence of potassium bromide and bpy results in the formation of [C₆H₂{PdBr(bpy)}₂-1,4-(CHO)₂-2,5] (21), from which [C₆H₂{Pd(PPh₃)(bpy)}₂-1,4-(CHO) ₂-2,5](CF₃SO₃)₂ (22) can be prepared. The structures of 9·Me₂CO·1.5MeOH, 10·2CH₂Cl₂ and [Pd{C₆H₃(CH=NR)-2-(CHO)-5}(tmeda)]CF₃SO ₃ (R = C₆H₄NH₂-4) (12c′) have been determined by X-ray crystallography.

Full text of DOI:10.1021/om970583u

Organometallics 1997, 16, 5269-5282
5269
Syn th esis of Mer cu r y(II) a n d P a lla d iu m (II)
Or ga n om eta llic Der iva tives of Ter ep h th a ld eh yd e by
Meta la tion , Tr a n sm eta la tion , Oxid a tion , a n d
Con d en sa tion Rea ction s. X-r a y Cr ysta l Str u ctu r es of
tr a n s-[P d Cl{C6H3(CO2H)2-2,5}(P P h 3)2]‚Me2CO‚2MeOH,
tr a n s-[P d Cl{C6H3(CHO)-2-(CO2H)-5}(P P h 3)2]‚2CH2Cl2, a n d
[P d {C6H3(CHdNC6H4NH2-4)-2-(CHO)-5}(N,N,N′,N′-Tetr a -
m eth yleth ylen ed ia m in e)]CF 3SO3. Molecu la r Assem blies
th r ou gh [P d ]-Cl‚‚‚HO2C-Ar yl a n d
[P d ]-Cl‚‚‚HOMe HO(O)C-Ar yl Hyd r ogen Bon d s†
J ose´ Vicente,*,‡ J ose´-Antonio Abad,*,§ Barbara Rink,
Francisco-Santos Herna´ndez, and M. Carmen Ram´ırez de Arellano
Grupo de Quı´mica Organometa´lica,| Departamento de Quı´mica Inorga´nica, Facultad de
Quı´mica, Universidad de Murcia, Apartado 4021, Murcia, 30071 Spain
Received J uly 9, 1997X
The organomercurials [HgCl{C6H3(CHO)2-2,5}] (1) and [Hg{C6H3(CHO)2-2,5}2] (2) have
been prepared by mercuriation of terephthaldehyde. Palladium complexes [PdCl{C6H3-
(CHO)2-2,5}(N-N)] (N-N ) N,N,N′,N′-tetramethylethylenediamine (tmeda) (3) or 2,2′-
bipyridine (bpy) (3′)) or trans-[PdCl{C6H3(CHO)2-2,5}(PPh3)2]‚H2O (4) have been obtained
by reacting (Me4N)2[Pd2Cl6] or trans-[PdCl2(PPh3)2], respectively, with 1 or 2. The reaction
of potassium permanganate with complexes 3 and 3′ or mercurial 1 results in the selective
oxidation of the 5-formyl substituent affording [PdCl{C6H3(CHO)-2-(CO2H)-5}(N-N)] (N-N
) tmeda (5), bpy (5′)) or, respectively, a mixture whose major component is the fully oxidized
[HgCl{C6H3(CO2H)2-2,5}] (7) or a mixture of isomers [HgCl{C6H3(CHO)-2-(CO2H)-5}]/[HgCl-
{C6H3(CO2H)-2-(CHO)}] (8a /8b) depending on the molar ratio of the reagents. The reaction
of mixtures containing 7 or 8 with trans-[PdCl2(PPh3)2] give pure trans-[PdCl{C6H3(CO2H)2-
2,5}(PPh3)2] (9) or trans-[PdCl{C6H3(CHO)-2-(CO2H)-5}(PPh3)2] (10), respectively. Complexes
3 and 3′ react with amines and NaClO4‚H2O or Tl(CF3SO3) to give, depending of the reaction
conditions, cyclopalladated derivatives [Pd{C6H3(CHdNR)-2-(CHdNR)-5}(N-N)]+ or [Pd-
{C6H3(CHdNR)-2-(CHO)-5}(tmeda)]+. The mercurial 1 reacts with hydroxylamine to give
the mercuriated oxime [HgCl{C6H3(CHdNOH)2-2,5}] (14), which reacts with (Me4N)2[Pd2-
Cl6] to give the cyclopalladated complex [Pd{C6H3(CHdNOH)-2-(CHdNOH)-5}(µ-Cl)]2 (15).
From 15 some derivatives have been prepared. Complex 3 reacts with NH2OMe to give
[Pd{C6H3(CHdNOMe)-2-(CHdNOMe)-5}(tmeda)]ClO4(19). TheimineC6H4(CHdNTo)2-1,4(To
) C6H4Me-4) reacts with palladium(II) acetate to give the dipalladated imine [Pd{C6H2-
(CHdNTo)-2-{Pd(µ-OAc)}-4-(CHdNTo)-5}(µ-OAc)]n (20). Hydrolysis of 20 in the presence
of potassium bromide and bpy results in the formation of [C6H2{PdBr(bpy)}2-1,4-(CHO)2-
2,5] (21), from which [C6H2{Pd(PPh3)(bpy)}2-1,4-(CHO)2-2,5](CF3SO3)2 (22) can be prepared.
The structures of 9‚Me2CO‚1.5MeOH, 10‚2CH2Cl2 and [Pd{C6H3(CHdNR)-2-(CHO)-
5}(tmeda)]CF3SO3 (R ) C6H4NH2-4) (12c′) have been determined by X-ray crystallography.
In tr od u ction
their reactivity in order to find new types of chemical
behavior or applications for organic synthesis. In
particular, we have reported 2-amino-,1 2-nitro-,2
2-formyl-, 2-acetyl-,3 2-ethoxymethyl-,4 and 2-arylazo5
arylpalladium(II)5 complexes as well as orthopalla-
We are currently involved in the synthesis of func-
tionalized organometallic compounds and the study of
† Dedicated to professor Pascual Royo on the occasion of his 60th
birthday.
‡ E-mail: jvs@fcu.um.es.
(1) Vicente, J .; Abad, J . A.; Frankland, A. D.; Ram´ırez de Arellano,
M. C. Chem. Commun. 1997, 959 and references therein.
(2) Vicente, J .; Arcas, A.; Borrachero, M. V.; Mol´ıns, E. M. C. J .
Organomet. Chem. 1992, 441, 487 and references therein.
§ E-mail: jaab@fcu.um.es.
| WWW: http://www.scc.um.es/gi/gqo/.
X Abstract published in Advance ACS Abstracts, November 1, 1997.
S0276-7333(97)00583-9 CCC: $14.00 © 1997 American Chemical Society

5270 Organometallics, Vol. 16, No. 24, 1997
Vicente et al.
dated imines,6 primary amines,7 and phosphonium
salts.8 By reacting some of these complexes with
alkynes, different types of organopalladium(II) (e.g.,
alkyl,9 vinyl, π-allyl,4, 2-vinylaryl,10 and indenyl11 de-
rivatives) or organic compounds (indenones, indenols,3
benzofulvenes,12 and spirocyclic compounds3) have been
prepared. We have exploited different synthetic routes
to prepare these arylpalladium(II) compounds, such as
the oxidative-addition reaction, used for the preparation
of 2-aminoaryl derivatives,1,13 and the orthopalladation
process, used for the synthesis of palladated primary
amines7 or phosphonium salts.8 However, the use of
arylmercurials as transmetalating agents has been our
choice in many more instances.4,14-16
The arylpalladium(II) complexes containing the group
C6H(OMe)3-2,3,4-(CHO)-6 have been among the most
fruitful. The presence of the formyl group have been
used to prepare other derivatives by condensation of
amines or through the Wittig reaction to give orthopal-
ladated imines6 or 2-vinylarylpalladium(II) complexes,
respectively.10 From the latter, indenyl derivatives have
been isolated.11 The study of the reactivity of these
formylaryl complexes has led to the synthesis of indenols
and indenones3 or shown an unprecedented type of
rearrangement.6 These precedents prompted us to
prepare palladium(II) derivatives of terephthaldehyde.
We report in this paper the mercuriation of terephthal-
dehyde, the transmetalation to palladium of the 2,5-
diformylaryl group, and some condensation reactions
(with amines or hydroxilamines) or oxidation reactions
of the formyl group in the mercury(II) and palladium-
(II) derivatives. The resulting functionalized aryl com-
plexes are potentially interesting because of the possi-
bility of forming polymers or oligomers through hydrogen
bonds. This way of self-assembling molecules is of great
current interest.17-21 Finally, we have synthesized some
dipalladated derivatives of terephthaldehyde.
Exp er im en ta l Section
Reactions were carried out at room temperature and without
precautions to exclude atmospheric moisture, unless otherwise
stated. 3-Nitrobenzyl alcohol was used as the matrix for the
FAB mass spectra. Chromatographic separations were per-
formed as previously reported.3
Syn th esis of [HgCl{C6H3(CHO)2-2,5}] (1). A solution of
HgO (3.05 g, 14.1 mmol) and terephthaldehyde (2.01 g, 14
mmol) in CF3SO3H (19 cm3)/water (19 cm3) was stirred for 7 h
in an oil bath at 95 °C. After the mixture was cooled down to
room temperature, an aqueous solution (100 cm3) of NaCl (15
g, 256 mmol) was added, the suspension stirred overnight, and
then the solid filtered, washed with water (300 cm3), air-dried,
washed with diethyl ether (150 cm3), and dried again. Evapo-
ration of the ether washings gave unreacted terephthaldehyde
(205 mg).The solid was purified by 1,4-dioxane extraction in
a Soxhlet apparatus (about 10 h). Partial evaporation of the
dioxane (ca. 4 cm3) and addition of diethyl ether (40 cm3) gave
a white precipitate, which was filtered and air-dried to give
1. Yield: 2.0 g, 39%. Mp: 250 °C (dec). IR: ν(CdO) 1701
(s), 1670 (s) cm-1; ν(Hg-Cl) 328 (w) cm-1 1H NMR (200 MHz,
.
DMSO-d6, ppm): 10.19 (s, CHO, 1H), 10.09 (s, CHO, 1H), 8.24
3
(s, H6, 1H), 8.14 (d, H3, 1H, J HH ) 7.7 Hz), 7.99 (d, H4, 1H).
13C{1H} NMR (50 MHz, DMSO-d6, ppm): 194.7 (CHO), 193.4
(CHO), 152.3, 143.5, 139.3 (C1, C2, C5), 138.3, 134.1, 129.6
(C3, C4, C6). Anal. Calcd for C8H5ClHgO2: C, 26.03; H, 1.37.
Found: C, 25.92; H, 1.30.
Compound 1 was similarly prepared using 60% perchloric
acid as the solvent. The mercuriation was conducted behind
a protective barricade.
Syn th esis of [Hg{C6H3(CHO)2-2,5}2] (2). A mixture of 1
(1.00 g, 2.71 mmol) and (Me4N)Cl (358 mg, 3.27 mmol) in
acetone (20 cm3) was refluxed for 12 h. Partial evaporation
of the solvent (ca. 4 cm3) and addition of water (125 cm3) led
to the precipitation of a solid, which was filtered and succes-
sively washed with water, ethanol, and diethyl ether and air-
dried to give 2 as a white solid. Yield: 566 mg, 45% over total
mercury. Mp: ca. 250 °C (dec). IR: ν(CdO) 1664 (s, br), 1668
(s, br) cm-1.1H NMR (200 MHz, DMSO-d6, ppm): 10.43 (s,
CHO, 1H), 10.18 (s, CHO, 1H), 8.41 (s br, H6, 1H), 8.24 (d,
3
4
H3, 1 H), 8.00 (dd, H4, 1H, J HH ) 8.3 Hz, J HH ) 2.0 Hz). 13C
NMR: not soluble enough. Anal. Calcd for C16H10HgO4: C,
41.17; H, 2.16. Found: C, 40.56; H, 2.01. The insolubility of
2 prevented further purification.
(3) Vicente, J .; Abad, J . A.; Gil-Rubio, J . Organometallics 1996, 15,
3509 and references therein.
(4) Vicente, J .; Abad, J . A.; Ferna´ndez-de-Bobadilla, R.; J ones, P.
G.; Ram´ırez de Arellano, M. C. Organometallics 1996, 15, 24 and
references therein.
(5) Vicente, J .; Arcas, A.; Bautista, D.; J ones, P. G. Organometallics
1997, 16, 2127 and references therein.
(6) Vicente, J .; Abad, J . A.; Gil-Rubio, J .; J ones, P. G.; Bembenek,
E. Organometallics 1993, 12, 4151 and references therein.
(7) Vicente, J .; Saura-Llamas, I.; Palin, M. G.; J ones, P. G.; Ramı´rez
de Arellano, M. C. Organometallics 1997, 16, 826 and references
therein.
(8) Vicente, J .; Chicote, M. T.; Lagunas, M. C.; J ones, P. G.;
Bembenek, E. Organometallics 1994, 13, 1243 and references therein.
(9) Vicente, J .; Saura-Llamas, I.; Palin, M. G.; J ones, P. G. J . Chem.
Soc., Dalton Trans. 1995, 2535 and references therein.
(10) Vicente, J .; Abad, J . A.; Bergs, R.; J ones, P. G.; Bautista, D. J .
Chem. Soc., Dalton Trans. 1995, 3093 and references therein.
(11) Vicente, J .; Abad, J . A.; Bergs, R.; J ones, P. G.; Ram´ırez de
Arellano, M. C. Organometallics 1996, 15, 1422 and references therein.
(12) Vicente, J .; Abad, J . A.; Gil-Rubio, J .; J ones, P. G. Organome-
tallics 1995, 14, 2677 and references therein.
(13) Vicente, J .; Abad, J . A.; Sa´nchez, J . A. J . Organomet. Chem.
1988, 352, 257 and references therein.
(14) Vicente, J .; Abad, J . A.; Gil-Rubio, J .; J ones, P. G. Inorg. Chim.
Acta 1994, 222, 1 and references therein.
Syn th esis of [P d Cl{C6H3(CHO)2-2,5}(tm ed a )] (3).
A
mixture of (Me4N)2[Pd2Cl4(µ-Cl)2] (300 mg, 0.52 mmol), 1 (385
mg, 1.04 mmol), and (Me4N)Cl (132 mg, 1.2 mmol) in acetone
(60 cm3) was stirred for 1 h at room temperature and 5 h at 0
°C and then filtered through Celite. The resulting yellow
solution was added to a solution of N,N′-tetramethylethylene-
diamine (0.156 cm3, 1.04 mmol) in acetone (6 cm3). After 15
min, the mixture was filtered through Celite. The solvent was
removed, and the residue was treated with dichloromethane
and filtered over Celite; the resulting solution was washed with
water and dried with MgSO4. Partial evaporation of the
solvent (ca. 4 cm3) and addition of n-pentane (20 cm3) led to
the precipitation of crude 3 as a yellow precipitate. This
product was purified by chromatography through silica gel
with dichloromethane and dichloromethane/acetone (1:1).
Yield: 310 mg, 76%. Mp: ca. 140 °C (dec). IR: ν(CdO) 1660
(m), 1674 (s), 1688 (m), 1700 (s) cm-1. IR(CH2Cl2): 1686, 1698
cm-1
.
1H NMR (300 MHz, CDCl3, ppm): 11.23 (s, CHO, 1H),
(15) Vicente, J .; Chicote, M. T.; Martin, J .; Artigao, M.; Solans, X.;
Font-Altaba, M.; Aguilo´, M. J . Chem. Soc., Dalton Trans. 1988, 141
and references therein.
(16) Vicente, J .; Arcas, A.; Borrachero, M. V.; Molı´ns, E.; Miravitlles,
C. J . Organomet. Chem. 1989, 359, 127 and references therein.
(17) Burrows, A. D.; Chan, C.-W.; Chowdhry, M. M.; McGrady, J .
E.; Mingos, D. M. P. Chem. Soc. Rev. 1995, 24, 329.
(18) Burrows, A. D.; Mingos, D. M. P.; White, A. J . P.; Williams, D.
J . Chem. Commun. 1996, 97.
4
10.04 (s, CHO, 1H), 8.17 (d, H6, 1H, J HH ) 1.5 Hz), 7.81 (d,
3
H3, 1H, J HH ) 7.9 Hz), 7.53 (dd, H4, 1H), 3.1-2.5 (m, CH2,
4H), 2.73 (s, Me, 3H), 2.70 (s, Me, 3H), 2.59 (s, Me, 3H), 2.24
(s, Me, 3H), 13C{1H} NMR (50 MHz, DMSO-d6, ppm): 196.93
(CHO), 194.12 (CHO), 164.25 (quaternary carbons), 145.10
(quaternary carbon), 137.93 (CH), 136.09 (quaternary carbon),
126.20 (CH), 123.10 (CH), 62.18 (CH2), 57.72 (CH2), 51.73 (Me),
(19) Taylor, R.; Kennard, O. Acc. Chem. Res. 1984, 17, 320.
(20) Aakero¨y, C. B.; Seddon, K. R. Chem. Soc. Rev. 1993, 22, 397.
(21) MacDonald, J . C.; Whitsides, G. M. Chem. Rev. 1994, 94, 2383.
49.37 (Me), 48.00 (Me), 46.69 (Me). FAB MS: m/ z 355 (M+
Cl, 100), 221 (M+ - Cl - Aryl, 42). Anal. Calcd for
-

Hg(II) and Pd(II) Derivatives of Terephthaldehyde
Organometallics, Vol. 16, No. 24, 1997 5271
C14H21ClN2O2Pd: C, 42.99; H, 5.41; N, 7.16. Found: C, 43.10;
H, 5.38; N, 7.11.
(C6H15N2Pd, 15). Anal. Calcd for C14H21ClN2O3Pd: C, 41.30;
H, 5.20; N, 6.88. Found: C, 41.23; H, 5.17; N, 6.81.
Syn th esis of [P d Cl{C6H3(CHO)-2-(CO2H)-5}(bp y)] (5′).
This compound was similarly prepared from KMnO4 (148.6
mg, 0.940 mmol) and 3′ (304 mg, 0.705 mmol). After the
Syn th esis of [P d Cl{C6H3(CHO)2-2,5}(bp y)]‚H2O (3′). A
mixture of (Me4N)2[Pd2Cl4 (µ-Cl)2] (300 mg, 0.52 mmol), 1 (385
mg, 1.04 mmol), and (Me4N)Cl (132 mg, 1.2 mmol) in acetone
(60 cm3) was stirred for 1 h at room temperature and 5 h at 0
°C and then filtered through Celite. The resulting yellow
solution was added to a solution of 2,2′-bipyridine (163 mg,
1.04 mmol) in acetone (6 cm3). After 15 min, the mixture was
filtered through Celite. The solvent was removed, and the
residue was recrystallized from dichloromethane/diethyl ether
to obtain a precipitate, which was filtered, washed with diethyl
ether, and air-dried to give 3′ as a yellow solid. Yield: 370
mg, 78%. Mp: ca. 180 °C (dec). IR: ν(CdO) 1682 (s), 1696
.
addition of C2O4H2 2H2O (119 mg, 094 mmol), the suspension
was stirred for 1 h and filtered over Celite. The solvents were
partially evaporated (ca. 10 cm3), and a solid precipitated,
which was filtered, washed twice with water (10 cm3), air-
dried, washed with diethyl ether (10 cm3), and air-dried to give
5′ as a yellow solid. Yield: 134 mg, 43%. Mp: 206 °C. IR:
ν(CdO) 1717 (s), 1674 (vs), 1652 (vs) cm-1; ν(Pd-Cl) 345 (w)
cm-1 1H NMR (300 MHz, DMSO-d6, ppm): 13.07 (s br, CO2H,
.
1H), 11.08 (s, CHO, 1H), 9.02-7.55 (several m, CH, 11H). 13C-
{1H} NMR: not soluble enough. FAB MS: m/ z 411 (M+
-
(s) cm-1
.
1H NMR (300 MHz, CDCl3, ppm): 11.21 (s, CHO,
3
Cl, 23), 262 (Pd(bpy), 64). Anal. Calcd for C18H13ClN2O3Pd:
C, 48.35; H, 2.93; N, 6.27. Found: C, 48.17; H, 2.91; N, 6.42.
Syn th esis of [P d {C6H3(CHO)-2-(CO2H)-5}(P P h 3)(bp y)]-
CF 3SO3 (6). A solution of K(CF3SO3) (43 mg, 0.23 mmol) and
PPh3 (60 mg, 0.23 mmol) in acetone (24 cm3) was added
dropwise for 10 min to a suspension of 5′ (103 mg, 0.23 mmol)
in acetone (10 cm3). After the addition, the mixture was stirred
for a further 2 h. Filtration over Celite yielded a yellow
solution, which was evaporated to dryness. The resulting
yellow residue was dissolved in 50 cm3 of CH2Cl2 and washed
with 20 cm3 of water. The separated organic phase was dried
over MgSO4, filtered, and concentrated in vacuo (ca. 2 cm3).
Addition of 50 cm3 of diethyl ether gave a precipitate, which
was filtered and air-dried to give 6 as a yellow solid . Yield:
123 mg, 65%. Mp: 167 °C. IR: ν(CdO) 1679 (s) cm-1; ν(SO)
1H), 10.07 (s, CHO, 1H), 9.33 (d, bpy, 1H, J HH ) 5 Hz), 8.32
(d, bpy, 1H, J HH ) 1.5 Hz), 8.2-7.9 (m, bpy and ArH, 5H),
3
7.8-7.6 (m, bpy and ArH, 3H), 7.35-7.28 (m, bpy, 1H), 1.59
(s br, H2O, 2H). 13C{1H} NMR (75 MHz, CDCl3, ppm): 196.1
(CHO), 193.2 (CHO), 160.8, 156.5, 153.5 (quaternary carbons),
151.3 (CH), 149.7 (CH), 145.5 (quaternary carbon), 139.7 (CH),
139.4 (CH), 138.5 (CH), 137.6 (quaternary carbon), 128.4 (CH),
127.2 (CH), 127.0 (CH), 124.7 (CH), 122.6 (CH), 121.7 (CH).
FAB MS: m/ z 431 (M+, 13), 395 (M+ - Cl, 58), 262 (M+ - Cl
- Aryl, 100). Anal. Calcd for C18H15ClN2O3Pd: C, 48.13; H,
3.36; N, 6.24. Found: C, 48.07; H, 2.99; N, 6.06.
Syn th esis of tr a n s-[P d Cl{C6H3(CHO)2-2,5}(P P h 3)2]‚H2O
(4). A mixture of trans-[PdCl2(PPh3)2] (300 mg, 0.43 mmol),
1 (189 mg, 0.51 mmol), and (Me4N)Cl (114 mg, 1.03 mmol) in
acetone (30 cm3) was refluxed for 8 h and then filtered through
Celite. The solvent was removed, and the residue was
recrystallized from dichloromethane/hexane to obtain crude
4 as a yellow solid, which was purified by chromatography
through silica gel with dichloromethane/diethyl ether (10:1).
Yield: 194 mg, 55%. Mp: 190 °C dec. IR: ν(CdO) 1682 (s,
1027 (s), 634 (s) cm-1 1H NMR (200 MHz, DMSO-d6, ppm):
.
13.09 (s br, CO2H, 1H), 10.12 (s, CHO, 1H), 8.76-7.16 (several
m, CHarom, 26H). 31P{1H} NMR (121 MHz, DMSO-d6, ppm):
33.1 (s). FAB+ MS: m/ z 674 (M+, 23), 411 (M+ - PPh3, 63),
262 (Pd(bpy), 32). Anal. Calcd for C37H28F3N2O6PPdS: C,
53.99; H, 3.43; N, 3.40. Found: C, 53.96; H, 3.52; N, 3.41.
Syn t h esis of Cr u d e [H gCl{C6H 3(CO2H )2-2,5}] (7).
KMnO4 (684 mg, 3.7 mmol), dissolved in an acetone (72 cm3)/
water (18 cm3) mixture, was added dropwise for 25 min to a
solution of 1 (1.02 g, 2.77 mmol) in acetone (150 cm3); the
dropping funnel was washed with 12 cm3 of acetone, and the
solution was also added to the reaction mixture. The mixture
was then stirred for a 19 h more, during which time a brown
suspension was formed from the violet solution. Aqueous HCl
(0.1 M, 38 cm3) was then added, and the suspension was stirred
for 1 h and filtered over Celite to give a colorless solution. The
solvents were partially evaporated (ca. 30 cm3) to give a white
precipitate, which was filtered, washed with water, air-dried,
washed with ether, and dried again. Using this procedure,
922 mg of crude material was obtained. A Soxhlet extraction
with 1,4-dioxane yields an 8:1 molar mixture of 7 and 1 with
traces of mono-oxidized products (see Discussion). Yield: 793
mg, 64% (calcd from 1H NMR). IR: ν(CdO) 1681 (vs), 1673
br) cm-1
.
1H NMR (300 MHz, CDCl3, ppm): 10.17 (s, CHO,
1H), 9.47 (s, CHO, 1H), 7.7-7.1 (m, PPh3 and H6, 31H), 7.02
3
(d, H3, 1H, J HH ) 6.0 Hz), 6.91 (d, H4, 1H), 1.54 (s br, H2O,
2H). 13C{1H} NMR (50 MHz, CDCl3, ppm): 194.6 (CHO), 192.4
2
3
(CHO), 169.9 (t, C1, J PC ) 5.6 Hz), 143.7 (t, C2, J PC ) 2.2
Hz), 138.7 (t, C6, 3J PC ) 4.0 Hz), 136.6 (C5), 134.3 (t, o-C PPh3,
2J PC ) 6.3 Hz), 130.7 (C3 or C4), 130.2 (p-C PPh3), 129.9 (i-C
PPh3, 1J PC ) 23.3 Hz), 128.2 (t, m-C PPh3, 3J PC ) 5.2 Hz), 122.7
(C3 or C4). 31P{1H} NMR (121 MHz, CDCl3, ppm): 24.96 (s).
FAB MS: m/ z 798 (M+, 28), 764 (M+ - Cl, 17), 630 (M+ - Cl
- Aryl, 99). Anal. Calcd for C44H37ClO3P2Pd: C, 64.64; H,
4.56. Found: C, 64.68; H, 4.31.
Syn t h esis of [P d Cl{C6H 3(CH O)-2-(CO2H )-5}(t m ed a )]
(5). A solution of KMnO4 (162 mg, 1.02 mmol) in an acetone
(24 cm3)/water (6 cm3) mixture was added dropwise for 35 min
into a solution of 3 (300 mg, 0.77 mmol) in acetone (55 cm3);
the dropping funnel was washed with acetone (4 cm3), which
was also added to the reaction mixture. The mixture was then
(vs) cm-1; ν(HgCl) 339 (s) cm-1
.
1H NMR (200 MHz, DMSO-
stirred for
a further 22 h, during which time a brown
4
d6, ppm): 13.39 (s br, CO2H, 2H), 8.25 (d, H6, 1H, J HH ) 1.5
Hz), 8.14 (d, H3, 1H, 3J HH ) 8.1 Hz), 7.89 (dd, H4, 1H). Anal.
Calcd for C8H5ClHgO4: C, 23.95; H, 1.26. Found: C, 24.71;
H, 1.34.
suspension was formed from the violet solution. A solution of
C2O4H2‚2H2O (129 mg, 1.02 mmol) in acetone (10 cm3)/water
(10 cm3) was then added dropwise, and the suspension was
stirred for a further 2 h and subsequently filtered over Celite
to give a yellow solution. The solvents were partially evapo-
rated (ca. 10 cm3) and extracted with CH2Cl2 (100 cm3). The
water phase was extracted again with CH2Cl2 (2 × 25 cm3).
The organic layers were added together, dried over MgSO4,
filtered, and partially evaporated (ca. 3 cm3). Addition of
diethyl ether (30 cm3) and hexane (40 cm3) caused the
precipitation of a solid, which was filtered and air-dried to give
5 as a yellow solid. Yield: 141 mg, 45%. Mp: 172 °C. IR:
Syn th esis of th e Mixtu r e [HgCl{C6H3(CHO)-2-(CO2H)-
5}]/[HgCl{C6H3(CO2H)-2-(CHO)-5}] (8a /8b). KMnO4 (286
mg, 1.81 mmol), dissolved in an acetone/water mixture (72/18
cm3), was added dropwise for 3 h to a solution of 1 (1.0 g, 2.71
mmol) in acetone (140 cm3); the dropping funnel was washed
with 4 cm3 of acetone, and the solution was also added to the
reaction mixture. The mixture was then stirred for a further
30 min, during which time a brown suspension was formed
from the violet solution. Aqueous HCl (0.1 M, 18.1 cm3) was
then added, and the suspension was stirred for 30 min more
and then filtered over Celite. The resulting colorless solution
was partially concentrated (ca. 20 cm3) to give a suspension,
which was filtered, washed with water, air-dried, washed with
diethyl ether, and dried again. Using this procedure, 842 mg
ν(CdO) 1691 (vs), 1668 (vs); ν(Pd-Cl) 323 cm-1
.
1H NMR (300
MHz, DMSO-d6, ppm): 12.97 (s br, CO2H, 1H), 11.24 (s, CHO,
4
3
1H), 8.19 (d, H6, 1H, J HH ) 1.4 Hz), 7.57 (d, H3, 1H, J HH
)
8.0 Hz), 7.50 (dd, H4, 1H), 2.75-2.50 (m, CH2), 2.58 (s, Me),
2.55 (s, Me), 2.51 (s, Me, 3H), 2.16 (s, Me). 13C{1H} NMR: not
soluble enough. FAB MS: m/ z 371 (M+ - Cl, 32), 221

5272 Organometallics, Vol. 16, No. 24, 1997
Vicente et al.
of crude material was obtained. A Soxhlet extraction with 1,4-
dioxane yields a 1.8/1 (1H NMR) mixture of 8a and 8b
contaminated with traces of 1. Yield: 312 mg, ca. 30% (calcd
from 1H NMR). IR: ν(CdO) 1697 (s), 1675 (s) cm-1; ν(HgCl)
NMe, 6H), 1.64 (s br, H2O, 2H). Anal. Calcd for C28H37ClN4O5-
Pd: C, 51.62; H, 5.72; N, 8.60. Found: C, 51.41; H, 5.56; N,
8.24.
R ) C6H4Bu n -4, N-N ) tm ed a , X ) ClO4 (11b). This
compound was similarly prepared from 3 (215 mg, 0.55 mmol),
NaClO4 (309 mg, 2.20 mmol), and p-butylaniline (352 µl, 2.20
mmol) in toluene (70 cm3), 2 h reflux. Yield: 200 mg, 51%.
330 (w) cm-1 1H NMR (200 MHz, DMSO-d6, ppm): 13.50 (s
.
br, CO2H, 2H), 10.18 (s, CHO), 10.08 (s, CHO), 8.4-7.8 (several
multiplets, aromatic Hs). Anal. Calcd for C8H5ClHgO3: C,
24.95; H, 1.31. Found: C, 25.34; H, 1.25.
Mp: 200 °C. IR: ν(CdN) 1601 (s) cm-1 1H NMR (300 MHz,
.
CDCl3, ppm): 8.49 (s, CHdN, 1H), 8.01 (s, CHdN, 1H), 7.95
(s, H6, 1H), 7.65 (d, H3 or H4, 1H, 3J HH ) 7.8 Hz), 7.50 (d, H4
or H3, 1H), 7.31-7.17 (m, C6H4Bu, 8H), 3.11 (s, NMe, 6H),
3.00 (m, CH2, 2H), 2.74 (m, CH2, 2H), 2.65 (apparent q, CH2,
4H), 2.16 (s, NMe, 6H), 1.62 (m, CH2, 4H), 1.34 (m, CH2, 4H),
0.94 (t, Me, 6H). 13C{1H} NMR (50 MHz, CDCl3, ppm): 179.4
(CHdN), 158.0 (CHdN), 155.4, 148.7, 148.4, 146.2, 143.9,
141.8, 138.2 (quaternary carbons), 131.2 (CH), 130.0 (CH),
129.5 (2CH), 129.2 (2CH), 126.8 (CH), 123.1 (2CH), 121.1
(2CH), 64.4 (CH2), 60.4 (CH2), 51.6 (NMe), 48.1 (NMe), 35.2
(CH2), 35.1 (CH2), 33.6 (CH2), 33.3 (CH2), 22.3 (CH2), 22.2
(CH2), 13.9 (2Me). FAB+ MS: m/ z 617 (M+ - ClO4, 100). Anal.
Syn th esis of tr a n s-[P d Cl{C6H3(CO2H)2-2,5}(P P h 3)2] (9).
[PdCl2(PPh3)2] (310 mg, 0.44 mmol), crude 7 (276 mg, ca. 0.7
mmol), and (Me4N)Cl (156 mg, 1.0 mmol) were mixed in
acetone (80 cm3)/1,4-dioxane (10 cm3) and stirred for 5 h at 62
°C. The solvents were then partially evaporated (ca. 2 cm3),
and CH2Cl2 (80 cm3) was added, forming a suspension which
was filtered, and the resulting solid was air-dried to give 9 as
a colorless solid. The yellowish filtered solution was partially
evaporated (ca. 5 cm3), and the addition of hexane (70 cm3)
gave a suspension, which was filtered to give unreacted PdCl2-
(PPh3)2 (57 mg, 18%). The filtered yellow solution was
concentrated to dryness, yielding traces of complex 4 (by 1H
NMR). Yield of 9: 264 mg, 88% (based on reacted [PdCl2-
Calcd for
C34H47ClN4O4Pd: C, 56.91; H, 6.60; N, 7.81.
Found: C, 56.85; H, 6.49; N, 7.83.
(PPh3)2]). Mp: 209 °C. IR: ν(CO2) 1674 (vs), 1278 (br, s) cm-1
.
R ) C6H4Bu n -4, N-N ) bp y, X ) ClO4 (11′b). This
compound was similarly prepared from 3′ (210 mg, 0.49 mmol),
NaClO4 (274 mg, 2.1 mmol), p-butyl aniline (0.234 cm3, 1.46
mmol), and a few crystals of p-MeC6H4SO3H in toluene (70
cm3), reflux. 14 h . Yield: 180 mg, 49%. Mp: 149 °C. IR:
1H NMR (300 MHz, DMSO-d6, ppm): 12.50 (s br, CO2H, 2H),
7.72 (s, H6, 1H), 7.52-7.26 (m, PPh3, 30H), 6.93 (d, H3 or H4,
1H, J HH ) 8.3 Hz), 6.85 (d, H4 or H3, 1H). 13C{1H} NMR:
3
not soluble enough. 31P{1H} NMR (121 MHz, DMSO-d6,
ppm): 27.4 (s). FAB MS: m/ z 794 (M+ - Cl, 3), 534 (M+
-
ν(CdN) 1596 (s) cm-1; ν(ClO4), 1086 (vs) cm-1 1H NMR (200
.
MHz, CDCl3, ppm): 8.50 (s, CHdN, 1H), 8.31 (s, CHdN, 1H),
8.59-7.20 (several m, CH, 21H), 2.67 (apparent q, CH2, 4H),
Cl - PPh3, 9). Anal. Calcd for C44H35ClO4P2Pd: C, 63.55; H,
4.24. Found: C, 63.46; H, 4.12. Crystals of 9 were grown by
slowly cooling (-20 °C) a saturated solution of 9 in ca. 1:1:1
(v:v:v) acetone/methanol/dichloromethane solution.
3
1.62 (m, CH2, 4H), 1.37 (m, CH2, 4H), 0.96 (t, Me, 3H, J HH
)
7.1 Hz), 0.95 (t, Me, 3H, J HH ) 7.2 Hz). 13C{1H} NMR (50
MHz, CDCl3, ppm): 177.4 (CHdN), 157.8 (CHdN), 157.1,
148.9, 148.2, 144.8, 144.5, 142.0, 136.6 (quaternary carbons),
141.1 (CH), 137.0 (CH), 131.8 (CH), 130.2 (CH), 129.9 (2CH),
129.2 (2CH), 129.0 (CH), 126.9 (2CH), 126.8 (CH), 124.2 (2CH),
122.4 (2CH), 121.3 (CH), 35.2 (CH2), 35.1 (CH2), 33.6 (CH2),
33.3 (CH2), 22.3 (CH2), 22.1 (CH2), 13.9 (Me), 13.8 (Me). FAB+
3
Syn t h esis of tr a n s-[P d Cl{C6H 3(CH O)-2-(CO2H )-5}-
(P P h 3)2] (10). trans-[PdCl2(PPh3)2] (350 mg, 0.5 mmol), the
mixture of mercurials 8a /8b (208 mg, ca. 0.54 mmol), and
(Me4N)Cl (230 mg, 2.10 mmol) were dissolved in acetone (35
cm3)/1,4-dioxane (10 cm3) and stirred for 4 h at 62 °C. The
resulting gray suspension was filtered over Celite, and the
yellow solution obtained was evaporated to dryness. The
residue was suspended in CH2Cl2 (20 cm3) and stirred for 2 h.
The insoluble solid was filtered off, giving 10 as a yellowish
solid. Yield: 162 mg, 40%. Mp: 210o C. IR: ν(CdO) 1715
MS: m/ z 657 (M+ - ClO4, 100). Anal. Calcd for C38H39
-
ClN4O4Pd: C, 60.25; H, 5.19; N, 7.40. Found: C, 60.37; H,
4.95; N, 7.68.
R ) C6H4NH2-4, N-N ) tm ed a , X ) ClO4 (11c). A solution
of 3 (112 mg, 0.29 mmol) in acetonitrile (80 cm3) was added
dropwise to a solution of NaClO4 (165 mg, 1.18 mmol) and
p-phenylenediamine (190 mg, 1.76 mmol) in acetonitrile (10
cm3) for 140 min; the mixture was then stirred for a further
17 h, during which time a color change from yellow to orange
brown was observed. The suspension was filtered, the result-
ing solution concentrated to dryness, the residue treated with
dichloromethane (50 cm3), and the suspension filtered. The
resulting solution was concentrated to dryness, and the red-
brown residue was dissolved in dichloromethane/acetone (10/
15 cm3). Addition of diethyl ether (25 cm3) gave 11c as an
orange solid. Yield: 57 mg, 31%. Mp: 287 °C (dec). IR:
ν(NH2) 3450 (m), 3357 (s) cm-1; ν(CdN) 1602 (vs) cm-1; ν(ClO4)
(s), 1675 (s) cm-1 1H NMR (200 MHz, DMSO-d6, ppm): 12.68
.
(s br, CO2H, 1H), 9.77 (s, CHO, 1H), 7.71 (s, H6, 1H), 7.51-
7.29 (m, Ph, 30H), 7.08 (d, H3 or H4, 1H, 3J HH ) 8.0 Hz), 6.70
(d, H4 or H3, 1H). 13C NMR: not soluble enough. 31P{1H}
NMR (121 MHz, DMSO-d6, ppm): 23.3 (s). FAB MS: m/ z
780 (M+ - Cl, 11), 517 (M+ - Cl - PPh3, 56). Anal. Calcd for
C44H35ClO3P2Pd: C, 64.80; H, 4.33. Found: C, 64.63; H, 4.32.
Colorless crystals were grown from a hot solution of 10 in
methanol and CH2Cl2 by slowly cooling the solution to room
temperature.
Syn th esis of [P d {C6H3(CHdNR)-2-(CHdNR)-5}(N-N)]X
(11). R ) C6H4Me-4, N-N ) tm ed a , X ) ClO4 (11a ).
A
1093 (vs) cm-1 1H NMR (200 MHz, DMSO-d6, ppm): 8.74 (s,
.
mixture of 3 (225 mg, 0.57 mmol), p-toluidine (123 mg, 1.15
mmol), NaClO4 (323 mg, 2.30 mmol), and p-MeC6H4SO3H (a
few crystals) in toluene (70 cm3) was refluxed for 20 h in a
Soxhlet containing CaH2 in the extraction thimble. The
solvent was then evaporated, and the residue was extracted
with dichloromethane and then filtered through Celite to give
an orange solution. Partial evaporation of the solvent (ca. 4
cm3) and addition of diethyl ether (20 cm3) led to a suspension
which was filtered, and the solid was recrystallized from
dichloromethane/diethyl ether, washed with diethyl ether, and
air-dried to give 11a ‚H2O as an orange solid. Yield: 232 mg,
62%. Mp: 170 °C dec. ΛM (acetone, 5 × 10-4 mol L-1): 120
CHdN, 1H), 8.32 (s, CHdN, 1H), 7.87 (s, H6, 1H), 7.72 (d, H3
3
or H4, 1H, J HH ) 7.8 Hz), 7.61 (d, H4 or H3, 1H), 7.21 (d,
3
3
CHarom, 2H, J HH ) 8.5 Hz), 7.03 (d, CHarom, 2H, J HH ) 8.5
3
Hz), 6.64 (d, CHarom, 2H, J HH ) 8.5 Hz), 6.61 (d, CHarom, 2H,
3J HH ) 8.5 Hz), 5.47 (s, NH2, 2H), 5.38 (s, NH2, 2H), 2.99 (s,
NMe, 6H), 2.81 (m, CH2, 2H), 2.65 (m, CH2, 2H), 2.14 (s, NMe,
6H). 13C NMR: not soluble enough. FAB+ MS: m/ z 535 (M+
- ClO4, 100). Anal. Calcd for C26H33ClN6O4Pd: C, 49.14; H,
5.23; N, 13.23. Found: C, 48.49; H, 5.11; N, 12.62. The low
solubility of 11c prevented further purification.
R ) C6H4NH2-4, N-N ) bp y, X ) ClO4 (11′c). This
compound was similarly prepared from 3′ (206 mg, 0.48 mmol)
in acetonitrile (80 cm3), NaClO4 (280 mg, 1.99 mmol), and
p-phenylenediamine (310 mg, 2.867 mmol) in acetonitrile (18
cm3) Yield: 90 mg, 28%. Mp: 250 °C (dec). IR: ν(NH2) 3455
(m), 3357 (s) cm-1; ν(CdN) 1608 (vs), 1600 (vs) cm-1; ν(ClO4)
Ω-1 cm2 mol-1 IR: ν(CdN) 1594 (s, br) cm-1
.
1H NMR (300
MHz, CDCl3, δ): 8.49 (s, CHdN, 1H), 8.00 (s, CHdN, 1H),
3
7.93 (s, H6, 1H), 7.65 (d, H3, 1H, J HH ) 7.8 Hz), 7.51 (d, H4,
1H), 7.4-7.1 (m, 2C6H4Me, 8H), 3.11 (s, NMe, 6H), 3.1-2.6
(m, CH2, 4H), 2.40 (s, CMe, 3H), 2.38 (s, CMe, 3H), 2.17 (s,

Hg(II) and Pd(II) Derivatives of Terephthaldehyde
1093 (vs) cm-1 1H NMR (300 MHz, DMSO-d6, ppm): 8.65 (s,
Organometallics, Vol. 16, No. 24, 1997 5273
.
to give 12c′ as an orange powder. Yield: 238 mg, 83%. Mp:
211 °C (dec). IR: ν(NH2) 3444, 3343 (w) cm-1; ν(CdO) 1685
CHdN, 1H), 8.56 (s, CHdN, 1H), 8.68-7.65 (several m, CHarom
,
11H), 7.39 (d, CHarom, 2H, 3J HH ) 8.7 Hz), 7.19 (d, CHarom, 2H,
(s) cm-1; ν(CdN) 1602 (s) cm-1; ν(SO) 1025 (s), 636 (s) cm-1
.
3J HH ) 8.7 Hz), 6.67 (d, CHarom, 2H, J HH ) 8.7 Hz), 6.61 (d,
1H NMR (200 MHz, DMSO-d6, ppm): 10.08 (s, CHO, 1H), 8.43
(s, CHdN, 1H), 7.87 (s, H6, 1H), 7.73 (s br, H3, H4, 2H), 7.04
3
3
CHarom, 2H, J HH ) 8.7 Hz), 5.68 (NH2, 2H, s), 5.39 (NH2, 2H,
3
s). 13C NMR: not soluble enough. FAB+ MS: m/ z 575 (M+
- ClO4, 6.0). Anal. Calcd for C30H25ClN6O4Pd: C, 53.45; H,
3.73; N, 12.44. Found: C, 53.28; H, 3.73; N, 11.60.
(d, CHarom, 2H, J HH ) 8.5 Hz), 6.63 (d, CHarom, 2H), 5.50 (s,
NH2, 2H), 2.96 (s, NMe, 6H), 2.87 (m, CH2, 2H), 2.66 (m, CH2,
2H), 2.14 (s, NMe, 6H). 13C{1H} NMR: the product decom-
poses during the experiment. FAB+ MS: m/ z 446 (M+ - CF3-
SO3, 100). Anal. Calcd for C21H27FN4O4PdS: C, 42.40; H,
4.57; N, 9.42. Found: C, 42.48; H, 4.55; N, 9.25. Orange
crystals were grown by diffusion of diethyl ether into a
saturated solution of 12c′ in dichloromethane.
Syn th esis of [P d {C6H3(CHdNR)-2-(CHO)-5}(tm ed a )]X
(12). R ) C6H4Bu -4, X ) ClO4 (12b). A solution of 3 (210
mg, 0.54 mmol) in acetonitrile (74 cm3) was added dropwise
to a solution of NaClO4 (297 mg, 2.11 mmol) and 4-butylaniline
(0.085 cm3, 0.53 mmol) in acetonitrile (14 cm3) for 10 min, and
the mixture was then stirred for a further 22 h. The aceto-
nitrile was then evaporated, and the residue was dissolved in
dichloromethane (50 cm3), filtered over Celite, and concen-
trated in vacuo (ca. 8 cm3). Addition of diethyl ether (50 cm3)
and filtration of the resulting suspension gave 12b as a light
yellow solid. Yield: 200 mg, 64%. Mp: 111 °C. IR: ν(CO)
Syn t h esis of [P d {C6H 3(CHdNC6H 4Bu n -4′)-2-(CHdN-
C6H4NH2-4′)-5}(tm ed a ]ClO4 (13). A solution of 12b (107 mg,
0.182 mmol) in 25 cm3 of acetonitrile was added dropwise for
15 min to a solution of 1,4-phenylenediamine 7 (59 mg, 0.547
mmol) in 10 cm3 of acetonitrile, and the mixture was then
stirred for a further 4 h, during which time the color of the
solution changed from yellow to orange. The acetonitrile was
then evaporated, and the residue was dissolved in 40 cm3 of
dichloromethane, filtered over MgSO4/Celite, and concentrated
(ca. 5 cm3). Addition of diethyl ether (40 cm3), filtration of
the resulting suspension, and air drying gave 13 as an orange
solid. Yield: 55 mg, 45%. Mp 245 °C (dec). IR: ν(NH2) 3434
(w), 3361 (w) cm-1; ν(CdN) 1615 (s), 1608 (s) cm-1; ν(ClO4)
1680 (vs) cm-1; ν(CN) 1602 (s) cm-1
.
1H NMR (300 MHz,
CDCl3, ppm): 10.02 (s, CHO, 1H), 8.11 (s, CHdN, 1H), 7.77
(s, H6, 1H), 7.68 (d, H3 or H4, 1H, 3J HH ) 7.5 Hz), 7.63 (d, H4
or H3, 1H), 7.30 (d, CHarom, 2H, 3J HH ) 8.3 Hz), 7.21 (d, CHarom
,
2H, 3J HH ) 8.3 Hz), 3.08 (s, NMe, 6H), 2.79 (m, CH2, 2H), 2.76
3
(m, CH2, 2H), 2.65 (t, CH2, 2H, J HH ) 7.8 Hz), 2.16 (s, NMe,
6H), 1.61 (quintuplet, CH2, 2H, 3J HH ) 7.8 Hz), 1.35 (sext, CH2,
1091 (s) cm-1 1H NMR (200 MHz, DMSO-d6, ppm): 8.76 (s,
.
CHdN, 1H), 8.43 (s, CHdN, 1H), 7.89 (s, H6, 1H), 7.75 (d, H3
3
3
2H, J HH ) 7.8 Hz), 0.94 (t, Me, 3H, J HH ) 7.5 Hz). 13C{1H}
NMR (50 MHz, CDCl3, ppm): 192.1 (CHO), 179.6 (CHdN),
155.9, 151.5, 146.0, 144.3, 136.5 (quaternary carbons), 131.2
(CHarom, 1C), 130.2 (CHarom, 1C), 129.6 (CHarom, 2C), 128.4
(CHarom), 122.9 (CHarom), 64.4 (CH2), 60.5 (CH2), 51.6 (NMe),
48.2 (NMe), 35.1 (CH2), 33.4 (CH2), 22.2 (CH2), 13.9 (Me).
FAB+ MS: m/ z 486 (M+ - ClO4, 100). Anal. Calcd for
C24H34ClN3O5Pd: C, 49.16; H, 5.84; N, 7.17. Found: C, 49.40;
H, 5.89; N, 7.08.
3
or H4, 1H, J HH ) 7.9 Hz), 7.63 (d, H4 or H3, 1H), 7.38-7.14
3
(m, CHarom, 6H), 6.62 (d, CHarom, 2H, J HH ) 8.5 Hz), 5.40 (s,
NH2, 2H), 3.00 (s, NMe, 6H), 2.92 (m, CH2, 2H), 2.71-2.62
(m, CH2, 4H), 2.08 (s, NMe, 6H), 1.58 (m, CH2, 2H), 1.30 (m,
3
CH2, 2H), 0.90 (t, Me, 3H, J HH ) 7.2 Hz). 13C NMR: not
soluble enough. FAB+ MS: m/ z 577 (M+ - ClO4, 15.3). Anal.
Calcd for
C30H40ClN5O4Pd: C, 53.26; H, 5.96; N, 10.35.
Found: C, 51.61; H, 5.56; N, 10.25. (See Discussion).
R ) C6H4NH2-4, X ) ClO4 (12c). A solution of 3 (201 mg,
0.514 mmol) in acetonitrile (50 cm3) was added dropwise to a
solution of NaClO4 (108 mg, 0.771 mmol) and p-phenylenedi-
amine (56 mg, 0.51 mmol) in acetonitrile (10 cm3) for 70 min.
The mixture was then stirred for a further 19 h, during which
time a color change from yellow to orange was observed. The
acetonitrile was then evaporated, and the residue was dis-
solved in acetone (30 cm3). The solvents were then evaporated,
dichloromethane (30 cm3) was added to the residue, and the
suspension was stirred and filtered. The solid was air-dried,
washed with water (40 cm3), dichloromethane (10 cm3), and
diethyl ether (10 cm3), and air-dried to give 12c as an orange
solid. Yield: 180 mg, 64%. Mp: 212 °C (dec). IR: ν(NH2)
3450, 3356 (w) cm-1; ν(CdO) 1674 (s) cm-1; ν(CdN) 1602 (s)
Syn th esis of [HgCl{C6H3(CHdNOH)2-2,5}] (14). A solu-
tion of NH2OH‚HCl (150 mg, 2.17 mmol) and NaOH (86 mg,
2.17 mmol) in methanol (15 cm3) was added to a suspension
of 1 (80 mg, 0.22 mmol) in methanol (5 cm3). The resulting
colorless solution was stirred for 15 min, the solvent evapo-
rated, and the residue washed with water and filtered. The
resulting solid was air-dried, giving 14 as a white solid.
Yield: 72 mg, 83%. Mp: 273 °C (dec.) IR: ν(OH) 3478 (m,
br), 3284 (s, br) cm-1; ν(CdN) 1682 (m, br), 1584 (m) cm-1
;
ν(HgCl) 326 cm-1 1H NMR (200 MHz, acetone-d6, ppm): 10.93
.
(s, OH, 1H), 10.51 (s, OH, 1H), 8.31 (s, CHdN, 1H), 8.12 (s,
3
CHdN, 1H), 7.81 (s br, H6, 1H), 7.59 (dd, H4, 1H, J HH ) 8.0
4
Hz, J HH ) 1.5 Hz), 7.48 (d, H3, 1H). 13C{1H} NMR (50 MHz,
cm-1; ν(ClO4), 1104 (s) cm-1 1H NMR (300 MHz, DMSO-d6,
.
acetone-d6, ppm): 151.6 (CdNOH), 148.7 (CdNOH), 139.2,
135.8 (C2, C5), 136.3, 131.4, 127.7 (C3, C4, C6). Anal. Calcd
for C8H7ClHgN2O2: C, 24.07; H, 1.77; N, 7.02. Found: C,
24.15; H, 1.72; N, 6.80.
ppm): 10.09 (s, CHO, 1H), 8.44 (s, CHdN, 1H), 7.89 (s, H6,
3
1H), 7.75 (s br, H3, H4, 2H), 7.05 (d, CHarom, 2H, J HH ) 8.1
3
Hz), 6.64 (d, CHarom, 2H, J HH ) 8.1 Hz), 5.51 (s, NH2, 2H),
2.98 (s, NMe, 6H), 2.89 (m, CH2, 2H), 2.67 (m, CH2, 2H), 2.15
(s, NMe, 6H). 13C{1H} NMR (50 MHz, DMSO-d6, ppm): 193.6
(CHO), 179.9 (CHdN), 156.4, 152.1, 149.0, 137.5, 135.9
(quaternary carbons), 132.6 (CHarom), 130.1 (CHarom), 126.4
(CHarom), 123.9 (2CHarom), 113.4 (2CHarom), 63.5 (CH2), 59.6
Syn t h esis of [P d {C6H3(CHdNOH)-2-(CHdNOH)-5}(µ-
Cl)]2 (15). A mixture of (Me4N)2[Pd2Cl6] (292 mg, 0.51 mmol),
14 (406 mg, 1.02 mmol), and (Me4N)Cl (164 mg, 1.5 mmol) in
acetone (90 cm3) was refluxed for 4 h and then filtered through
Celite. The solvent was then evaporated, the residue washed
with water and filtered, and the resulting solid washed with
diethyl ether and air-dried to give 15 as a yellow solid. Yield:
(CH2), 50.7 (NMe), 47.3 (NMe). FAB+ MS: m/ z 445 (M+
-
ClO4, 100). Anal. Calcd for C20H27ClN4O5Pd: C, 44.05; H,
4.99; N, 10.27. Found: C, 44.26; H, 4.96; N, 9.47.
275 mg, 89%. Mp: 280 °C (dec). IR: ν(OH) 3280 (m, br) cm-1
;
R ) C6H4NH2-4, X ) CF 3SO3 (12c′). A solution of 3 (202
mg, 0.516 mmol) in acetonitrile (50 cm3) was added dropwise
to a solution of Tl(CF3SO3) (212 mg, 0.60 mmol) and p-
phenylenediamine (56 mg, 0.52 mmol) in acetonitrile (10 cm3)
for 15 min, and the mixture was then stirred for a further 18
h, during which time a color change from yellow to orange was
observed. The solvent was then evaporated, and the residue
was suspended in 100 cm3 of dichloromethane and filtered.
The resulting orange solution was partially evaporated (ca.
20 cm3), and 15 cm3 of acetone and 40 cm3 of ether were added
ν(CdN) 1631 (m, br) cm-1
.
1H NMR (200 MHz, DMSO-d6,
ppm): 11.34 (br, OH), 8.31 (br), 7.97 (br), 7.25 (br). 13C NMR:
not soluble enough. Anal. Calcd for C8H7ClN2O2Pd: C, 31.50;
H, 2.32; N, 9.19. Found: C, 31.94; H, 2.39; N, 8.80.
Syn t h esis
of
[(P h 3P )2N][P d {C6H 3(CH dNOH )-2-
(CHdNOH)-5}Cl2] (16). A mixture of 15 (154 mg, 0.25 mmol)
and [(Ph3P)2N]Cl (290 mg, 0.50 mmol) in acetone (10 cm3) was
stirred until all the solids had dissolved (4 h) and then filtered
through Celite. Partial evaporation of the solvent (ca. 4 cm3)

5274 Organometallics, Vol. 16, No. 24, 1997
Vicente et al.
and addition of diethyl ether (20 cm3) led to the precipitation
of a solid, which was filtered, washed with diethyl ether, and
air-dried to give 16 as a yellow solid . Yield: 393 mg, 89%.
C16H27N4ClO6Pd: C, 37.43; H, 5.34; N, 10.92. Found: C, 37.78;
H, 5.17; N, 10.93
Syn t h esis of [P d {C6H 2(CH dNTo)-2-{P d (µ-OAc)}-4-
Mp: 108 °C. ΛM (acetone, 5 × 10-4 mol L-1): 90 Ω-1 cm2 mol-1
.
1H NMR (300 MHz, acetone-d6, ppm): 11.40 (s, OH, 1H), 10.42
(CH dNTo)-5}(µ-OAc)]n (20).
A mixture of 1,4-C6H4-
4
(br, OH, 1H), 8.02 (d, CHdN, 1H, J HH ) 1.5 Hz), 7.95 (s,
(CHdNTo)2 (300 mg, 0.96 mmol) and Pd(OAc)2 (430 mg, 1.92
mmol) in toluene (90 cm3) was refluxed for 4 h in a Soxhlet
containing CaH2 in the thimble. The solvent was then
evaporated, the residue washed with water and filtered, and
the resulting solid washed with acetone, dichloromethane, and
diethyl ether and dried in the oven at 75 °C for 2 days to give
20 as a brown solid. Yield: 572 mg, 93%. Mp: 270 °C (dec).
IR: ν(CdO) 1578 (vs, br) cm-1; ν(CdN) 1560 (vs) cm-1. Anal.
Calcd for C26H24N2O4Pd2: C, 48.70; H, 3.77; N, 4.37. Found:
C, 48.69; H, 3.64; N, 4.19.
CHdN, 1H), 7.9-7.5 (m, (Ph3P)2N), H6, 31H), 7.21 (dd, H4,
3
4
1H, J HH ) 7.8 Hz, J HH ) 1.5 Hz), 7.12 (d, H3, 1H). 13C{1H}
NMR (75 MHz, acetone-d6, ppm): 154.4 (CdNOH), 152.9,
144.0, 133.8, 131.8, 125.3, 122.4 (C1-6), 149.5 (CdNOH),
134.0-135.0 (m, (Ph3P)2N), 132.5-133.5 (m, (Ph3P)2N), 129.5-
1
3
130.5 (m, (Ph3P)2N), 127.9 (dd, C-P, J CP ) 107.9 Hz, J CP
)
1.5 Hz). 31P{1H} NMR (121 MHz, acetone-d6, ppm): 21.43.
Anal. Calcd for C44H37Cl2N3O2P2Pd: C, 60.11; H, 4.25; N, 4.78.
Found: C, 60.23; H, 4.15; N, 4.41.
Syn th esis of [C6H2{P d Br (bp y)}2-1,4-(CHO)2-2,5] (21).
Complex 20 (200 mg, 0.31 mmol), NaBr (320 mg, 3.12 mmol),
and AcOH (40 drops) were added to a solution of 2,2′-bipyridine
(98 mg, 0,62 mmol) in a 54 cm3 mixture of acetone and water
(5:1). The resulting brown suspension was refluxed for 6.5 h
to give a solid, which was then filtered, washed with water,
acetone, dichloromethane, and diethyl ether, and dried in the
oven at 75 °C for 1 day to give 21 as a dark brown solid.
Yield: 120 mg, 47%. Mp: 246 °C (dec). IR: ν(CdO) 1666 (vs)
Syn t h esis of [P d {C6H3(CHdNOH)-2-(CHdNOH)-5}(µ-
O3SCF 3)]2 (17). A mixture of 15 (300 mg, 0.49 mmol) and
Tl(CF3SO3) (348 mg, 0.98 mmol) in acetonitrile (30 cm3) was
stirred for 4 h and filtered through Celite. Partial evaporation
of the solvent (ca. 4 cm3) and addition of diethyl ether (25 cm3)
led to the precipitation of a solid, which was filtered, recrystal-
lized from acetone/diethyl ether, washed with diethyl ether,
and dried in the oven at 75 °C for 2 days to give 17 as a yellow
solid. Yield: 158 mg, 38%. Mp: ca. 230 °C (dec). ΛM (acetone,
5 × 10-4 mol L-1): 62 Ω-1 cm2 mol-1. IR: ν(OH) 3198 (s, br)
cm-1
.
1H NMR (300 MHz, DMSO-d6, ppm): 10.95 (s, CHO,
3
3
2H), 9.20 (d, bpy, 2H, J HH ) 5 Hz), 8.66 (d, bpy, 4H, J HH
)
cm-1; ν(CdN) 1656 (m), 1628 (m) cm-1 1H NMR (300 MHz,
.
8 Hz), 8.4-8.2 (m, bpy, 4H), 8.0-7.1 (m, bpy, 6H), 7.84 (s, H3,
acetone-d6, ppm): 12.17 (s, OH, 1H), 10.86 (s br, OH, 1H), 8.58
(s, CHdN, 1H), 8.43 (s, CHdN, 1H), 7.68 (d, H3 or H4, 1 H,
H6, 2H). 13C NMR: not soluble enough. Anal. Calcd for
C
28H20Br2N4O2Pd2: C, 41.15; H, 2.47; N, 6.86. Found: C,
3
3J HH ) 6.9 Hz), 7.46 (s, H6 1H), 7.17 (d, H4 or 3, 1H, J HH
)
39.90; H, 2.37; N, 6.54. (See Discussion).
6.9 Hz). 1H NMR (300 MHz, acetone-d6 with some drops of
D2O, ppm): 8.54 (s, HCN, 1H), 8.34 (s, HCN, 1H), 7.59 (d, H3
or H4, 1H, 3J HH ) 7.7 Hz), 7.37 (s, H6, 1H), 7.06 (d, H3 or H4,
Syn th esis of [C6H2{P d (P P h 3)(bp y)}2-1,4-(CHO)2-2,5]-
(CF 3SO3)2 (22). A mixture of 21 (150 mg, 0.18 mmol), PPh3
(96 mg, 0.37 mmol), and K(CF3SO3) (69 mg, 0.37 mmol) in
acetone (30 cm3) was stirred for 30 min and then filtered
through Celite to give a yellow solution. Partial evaporation
of the solvent (ca. 4 cm3) and addition of diethyl ether (20 cm3)
led to a suspension which was filtered, and the solid was
washed with water and diethyl ether and dried in vacuo in a
dessicator over P2O5 for 2 days to give 22 as a yellow solid.
Yield: 219 mg, 80%. Mp: 198 °C (dec.). ΛM (acetone, 5 ×
1H, J HH ) 7.7 Hz). 13C{1H} NMR (75 MHz, acetone-d6,
3
ppm): 162.1 (CdNOH), 156.5 (CdNOH), 148.4, 145.4, 130.1
(C1, C2, C5), 132.8, 130.6, 129.3 (C3, C4, C6), 121.9 (q, CF3,
1J CF ) 320 Hz). 19F NMR (282 MHz, acetone-d6, ppm): -77.79
(s, CF3). Anal. Calcd for C9H7F3N2O5PdS: C, 25.82; H, 1.69;
N, 6.69; S, 7.66. Found: C, 25.66; H, 1.58; N, 6.72; S, 7.35.
Syn t h esis of [P d {C6H 3(CH dNOH )-2-(CH dNOH )-5}-
(bp y)]CF 3SO3 (18). A mixture of 17 (100 mg, 0.24 mmol) and
bpy (37 mg, 0.24 mmol) in acetone (15 cm3) was stirred for 1
h and then filtered through Celite. Partial evaporation of the
solvent (ca. 4 cm3) and addition of diethyl ether (20 cm3) gave
a suspension which was filtered, and the solid was washed
with diethyl ether and air-dried to give 18 as a yellow solid.
Yield: 94 mg, 68%. Mp: 145 °C. ΛM (acetone, 5 × 10-4 mol
L-1): 96 Ω-1 cm2 mol-1. IR: ν(OH) 3354 (m, br) cm-1; ν(CdN)
10-4 mol L-1): 174 Ω-1 cm2 mol-1. IR: ν(CdO) 1670 (vs) cm-1
.
1H NMR (300 MHz, DMSO-d6, ppm): 9.65 (s, CHO, 2H), 8.72
3
(d, bpy, 4H, J HH ) 8 Hz), 8.3-8.2 (m, bpy, 4H), 7.8-7.1 (m,
C6H2, bpy and PPh3, 40H). 13C NMR: not soluble enough. 31P-
{1H} NMR (121 MHz, DMSO-d6, ppm): 32.53. Anal. Calcd
for C66H50F6N4O8P2Pd2S2: C, 53.56; H, 3.41; N, 3.79. Found:
C, 53,54; H, 3,54; N, 3.59.
Cr ysta l Str u ctu r es. Crystals of 9‚Me2CO‚1.5MeOH, 10‚
2CH2Cl2, and 12c′ were mounted in inert oil on a glass fiber
and transferred to the diffractometer (Siemens P4 with LT2
low-temperature attachment) as summarized in Table 1. The
structures were solved by Patterson methods and refined
anisotropically on F2 (program SHELXTL).22
1602 (s) cm-1; ν(SO) 638 (vs) cm-1
.
1H NMR (200 MHz,
acetone-d6, -60 °C, ppm): 11.07 (s br, OH, 2H), 9.2-6.5
(several multiplets, C6H3 and bpy). 13C NMR: the compound
decomposes during the experiment. Anal. Calcd for
C19H15F3N4O5PdS: C, 39.70; H, 2.64; N, 9.75. Found: C, 39.54;
H, 2.74; N, 9.53.
For compound 9‚Me2CO‚1.5MeOH, the unit cell parameters
were determined from a least-squares fit of 73 accurately
centered reflections (7.2° < 2θ < 25.04°). Badly resolved
electron density near an inversion center was tentatively
Syn th esis of [P d {C6H3(CHdNOMe)-2-(CHdNOMe)-5}-
(tm ed a )]ClO4 (19). A solution of NH2OMe‚HCl (213 mg, 2.56
mmol) and NaOH (102 mg, 2.56 mmol) in methanol (15 cm3)
was added to a suspension of 3 (100 mg, 0.26 mmol) and
NaClO4‚H2O (108 mg, 0.77 mmol) in methanol (15 cm3). The
resulting yellow solution was stirred for 2 h, then the solvent
was removed, and the residue recrystallized from acetone/
diethyl ether to give 19 as a yellow solid, which was filtered,
washed with diethyl ether, and air-dried. Yield: 52 mg, 40%.
Mp: ca. 210 °C (dec). ΛM (acetone, 5 × 10-4 mol L-1): 127
refined isotropically as
a disordered methanol molecule.
Hydrogen atoms were included using a riding model or as rigid
methyl and hydroxide groups. Hydrogen atoms for the dis-
ordered solvent were not considered. Max ∆/σ ) 0.006, max
∆F ) 1.66 e Å3.
The unit cell parameters of 10‚2CH2Cl2 were determined
from a least-squares fit of 70 accurately centered reflections
(10.6° < 2θ < 25.0°). The hydrogen atom H01 was located in
a difference Fourier synthesis and refined with a restrained
O-H bond length. Other hydrogen atoms were included using
a riding model. Max ∆/σ ) 0.003, max ∆F ) 0.32 e Å3. The
Ω-1 cm2 mol-1
br), 624 (s) cm-1
.
IR: ν(CdN) 1584 (m) cm-1; ν(ClO) 1088 (s,
1H NMR (200 MHz, acetone-d6, ppm): 8.66
.
(s, CHdN, 1H), 8.21 (s, CHdN, 1H), 7.61 (s, H6, 1H), 7.51 (s
br, H3, H4, 2H), 4.20 (s, OMe, 3H), 3.94 (s, OMe, 3H), 3.12 (s,
NMe2, 6H), 2.89 (s, NMe2, 6H). 13C NMR: the compound
decomposes during the experiment. Anal. Calcd for
(22) Sheldrick, G. M. SHELXL 93; University of Go¨ttingen: Go¨t-
tingen, Germany, 1993.

Hg(II) and Pd(II) Derivatives of Terephthaldehyde
Organometallics, Vol. 16, No. 24, 1997 5275
Ta ble 1. Cr ysta l Da ta for 9‚Me2CO‚1.5MeOH, 10‚2CH2Cl2, a n d 12c′
compound
mol formula
mol wt
9‚Me2CO‚1.5MeOH
48.5H47ClO6.5P2Pd
937.65
10‚2CH2Cl2
C46H39Cl5O3P2Pd
985.36
12c′
C
C21H27F3 N4 O4 PdS
594.93
habit
prism
prism
tablet
color
source
a, Å
b, Å
colorless
liquid diffusion, Me2CO/MeOH
11.429(1)
11.906(1)
18.727(2)
73.27(1)
73.57(1)
69.16(1)
2234.0(1)
2
colorless
liquid diffusion, CH2Cl2/MeOH
14.605(1)
17.171(1)
17.156(2)
orange
liquid diffusion, Et2O/CH2Cl2
10.786(2)
10.998(2)
11.140(2)
74.991(12)
75.398(10)
82.864(14)
1232.8(4)
2
c, Å
R, deg
â, deg
γ, deg
V, Å3
4302.4(6)
4
Z
λ, Å
temp, K
0.710 73
173(2)
0.710 73
173(2)
0.710 73
173(2)
radiation
monochromator
space group
cryst size, mm
abs corr
Mo KR
Mo KR
Mo KR
graphite
P1h
graphite
Cmc21
graphite
P1h
0.54 × 0.32 × 0.22
0.44 × 0.40 × 0.38
0.42 × 0.35 × 0.11
ψ-scans
max/min transmission, %
diffractometer
scan method
2θ range, deg
h,k,l limits
no. of reflns measd
no. of indep reflns
Rint
0.960/0.876
Siemens P4
ω
6.2-50.0
(h, (k, -l
13503
7813
0.018
0.0370
0.1065
Siemens P4
ω
6.7-50.0
+h, -k, (l
3945
3866
0.013
0.0198
0.0474
Siemens P4
ω
6.1-50.0
-h, (k, (l
5507
4266
0.021
0.0362
0.0782
R1a
wR2b
a
b
2
R1 ) σ||Fo| - |Fc||/σ|Fo| for reflections with I > 2σI. wR2 ) [σ[w(Fo - Fc2)2]/σ[w(Fo2)2]]0.5 for all reflections; w-1 ) σ2(F2) + (aP)2 +
bP, where P ) (2Fc + Fo2)/3 and a and b are constants set by the program.
2
origin was fixed by the method of Flack and Schwarzenbach.23
The absolute structure was determined (Flack parameter x )
0.004(18)).24
holic solvents in the presence of acetic acid.25,30 Using
this method, we have mercuriated 3,4,5-trimethoxy
derivatives of benzaldehyde31 and benzoic acid.32 De-
activated arenes pose problems which, in some cases,
have been solved by using stronger electrophiles and/
or high-temperature reactions. The mercuriation of
benzoic acid, o-dichlorobenzene, benzaldehyde, nitroben-
zene, or benzophenone has been achieved using mer-
cury(II) perchlorate in 60-70% perchloric acid at room
temperature.33
The unit cell parameters of 12c′ were determined from a
least-squares fit of 81 accurately centered reflections (9.4° <
2θ < 27.0°). The structure was solved by Patterson methods
and refined anisotropically on F2 (program SHELXTL).22 The
triflate anion is disordered over two sites (50% occupancy), as
well as the N1-C11-C16-N2 fragment (54% and 46% oc-
cupancy). Hydrogen atoms were included using a riding model
or as rigid methyl groups. Hydrogen atoms for the N2 amino
group were not considered. Max ∆/σ ) 0.001, max ∆F ) 0.81
e Å3.
The programs use the neutral atom scattering factors, ∆f′
and ∆f′′, and absorption coefficients from the International
Tables for Crystallography (Wilson, A. J . C., Ed.; Kluwer
Academic Publishers: Dordrecht, The Netherlands, 1992; Vol.
C, Tables 6.1.1.4, 4.2.6.8, and 4.2.4.2, pp 500-502, 219-222,
and 193-199, respectively).
In order to mercuriate terephthaldehyde, we reacted
it under these conditions using mercury(II) oxide in 60%
aqueous perchloric acid at room temperature, but only
traces of the mercuriated compound could be detected.
The presence of the two deactivating formyl groups must
be responsible for the stronger deactivation of this arene
when compared with the ones mentioned above. How-
ever, when the same reaction is carried out at 90 °C
and the resultant perchloric solution is poured into
aqueous sodium chloride, the mercurial [HgCl{C6H3-
(CHO)2-2,5}] (1) can be obtained in an acceptable yield
(54%) (Scheme 1). However, to handle perchloric solu-
tions at this temperature can be dangerous, and so we
have changed the perchloric acid to trifluoromethane-
sulfonic (triflic) acid, which is much less dangerous, and
the triflato ligand possesses a coordination capacity
similar to that shown by the perchlorato ligand.34,35 The
reaction was carried out by mixing the arene and HgO
in a 1:1 volume mixture of triflic acid and water. After
Resu lts a n d Discu ssion
Mer cu r ia tion of Ter ep h th a ld eh yd e. The mercu-
riation of arenes is the most important method for the
synthesis of arylmercurials. These reactions have been
studied in great detail, revealing an electrophilic sub-
stitution mechanism.25-29 Normal or activated arenes
are easily mercuriated by mercury(II) acetate in alco-
(23) Flack, H. D.; Schwarzenbach, D. Acta Crystallogr. 1988, A44,
499.
(24) Flack, H. D. Acta Crystallogr. 1983, A39, 876.
(25) Larock, R. C. Organomercury Compounds in Organic Synthesis.
Reactivity and Structure; Springer-Verlag: Berlin, 1985.
(26) Fung, C. W.; Khorramdel-Vahed, M.; Ranson, R. J .; Roberts,
R. M. G. J . Chem. Soc., Perkin Trans. 2 1980, 267.
(27) Damude, L. C.; Dean, P. A. W. J . Chem. Soc., Chem. Commun.
1978, 1083.
(28) Damude, L. C.; Dean, P. A. W. J . Organomet. Chem. 1979, 181,
1.
(29) Olah, G. A.; Yu, S. H.; Parker, D. G. J . Org. Chem. 1976, 41,
1983.
(30) Sharp, T. M. J . Chem. Soc. 1937, 852.
(31) Vicente, J .; Abad, J . A.; Stiakaki, M. A.; J ones, P. G. J . Chem.
Soc., Chem. Commun. 1991, 137.
(32) Vicente, J .; Abad, J . A.; Sandoval, A.; J ones, P. G. J . Organomet.
Chem. 1992, 434, 1.
(33) Heck, R. F. J . Am. Chem. Soc. 1968, 90, 5518.
(34) Lawrance, G. A. Chem. Rev. 1986, 86, 17.
(35) Beck, W.; Su¨nkel, K. Chem. Rev. 1988, 88, 1405.

5276 Organometallics, Vol. 16, No. 24, 1997
Vicente et al.
Sch em e 1
Sch em e 3
Sch em e 2
of 1 with (Me4N)Cl. When 2 reacts with the palladium-
(II) chloro complexes, compound 1 is formed which, in
turn, is symmetrized again to 2 by the tetraalkyl-
ammonium salt. In fact, these transmetalating reac-
tions can also be carried out from 2, but using half of
the mercurial. We have previously used this method
in other cases.39
Oxid a tion Rea ction s of th e F or m yl Gr ou p s a n d
Tr a n sm eta la tion Rea ction s. We studied the KMnO4
oxidation of the formyl substituents of the previously
prepared 2,5-diformylphenylmercury(II) and -palladium-
(II) compounds. Thus, complexes 3 and 3′ react with
KMnO4 (1:1.3) to give complexes [PdCl{C6H3(CHO)-2-
(CO2H)-5}(tmeda)] (5) and [PdCl{C6H3(CHO)-2-(CO2H)-
5}(bpy)] (5′), respectively. Complex 5′ reacts with PPh3
and K(CF3SO3) to give the derivative [Pd{C6H3(CHO)-
2-(CO2H)-5}(PPh3)(bpy)](CF3SO3) (6) (Scheme 3).
The new mercurial [HgCl{C6H3(CO2H)2-2,5}] (7), in
which both CHO substituents have been oxidized, could
be obtained by reacting 1 with KMnO4 in a 4:1 acetone/
water mixture under the same conditions as for 5 and
5′. It did not prove possible to form this compound by
mercuriation of terephthalic acid (Scheme 4). The
product obtained is contaminated with very small
amounts of the two mono-oxidized isomers (by NMR
spectroscopy). An 1.8:1 mixture of these isomers, [HgCl-
{C6H3(CHO)-2-(CO2H)-5}] (8a ) and [HgCl{C6H3(CO2H)-
2-(CHO)}] (8b), can be obtained by reacting 1 with
KMnO4 in a 1:0.67 molar ratio. Crude 7 or the mixture
8a /8b reacted with trans-[PdCl2(PPh3)2] and (Me4N)Cl
in a mixture of acetone/1,4-dioxane at 62 °C to give pure
trans-[PdCl{C6H3(CO2H)-2,5}(PPh3)2] (9) or trans-[PdCl-
{C6H3(CHO)-2-(CO2H)-5}(PPh3)2] (10), respectively. Ac-
cording to the composition of the mixture of isomers 8a /
8b (64/36), the yield obtained in the synthesis of 10
(40%) is only compatible with the asumption that it
results from 8a . Because we have solved the crystal
structure of 10 (see below), the structure of 8a must be
that indicated in Scheme 4. We believe that the product
from 8b is insoluble and is separated with the insoluble
byproduct [HgCl3]- because, in the soluble part of the
crude of the reaction, we could not find neither 8b nor
any other P-containing compound in an appreciable
amount. The assignment of the substitution pattern in
5 is based on its reaction with PPh3 (1:2) giving 10.
In these reactions, the 5-CHO group has been oxidized
selectively, even when enough KMnO4 for the oxidation
completing the reaction, the mixture was poured into
aqueous NaCl in order to exchange the triflato group
for chloro to give 1. Polyhaloarenes have also been
mercuriated with mercury(II) trifluoroacetate in trif-
luoroacetic acid at temperatures ranging from 150 to
240 °C36,37 or with mercury(II) triflate in trifluoroacetic
acid at 73 °C.38 The mercurial 1 can be symmetrized
to the diarylmercurial [Hg{C6H3(CHO)2-2,5}2] (2) by
reaction with (Me4N)Cl, exploiting the formation of
insoluble Me4N[HgCl3] (Scheme 1). We have previously
used this reaction in order to obtain other diaryl-
mercurials.6,32,39
Tr a n sm et a la t ion R ea ct ion s. The reaction of
(Me4N)2[Pd2Cl6] with 1 in the presence of an excess of
(Me4N)Cl or with 2 in acetone at room temperature or
lower led to the formation of (Me4N)2[Pd2{C6H3(CHO)2-
2,5}2Cl2(µ-Cl)2] which, due to its thermal instability in
the solid state, could not be isolated as a pure compound.
However, addition of N,N,N′,N′-tetramethylethylene-
diamine (tmeda) or 2,2′-bipyridine (bpy) to these solu-
tions gave complexes [PdCl{C6H3(CHO)2-2,5}(tmeda)]
(3) or [PdCl{C6H3(C6H3(CHO)2-2,5}(bpy)] (3′) (Scheme
2). The mercurial 1 reacted with trans-[PdCl2(PPh3)2]
in boiling acetone, in the presence of (Me4N)Cl, to give
trans-[PdCl{C6H3(CHO)2-2,5}(PPh3)2] (4). The trans-
metalating agent in these processes seems to be the
diarylmercurial 2, formed by the in situ symmetrization
(36) Deacon, G. B.; Taylor, F. B. Aust. J . Chem. 1968, 21, 2675.
(37) Bertino, R. J .; Deacon, G. B.; Taylor, F. B. Aust. J . Chem. 1972,
25, 1645.
(38) Deacon, G. B.; Tunaley, D. J . Organomet. Chem. 1978, 156, 403.
(39) Vicente, J .; Bermu´dez, M. D.; Carrio´n, F. J .; J ones, P. G. Chem.
Ber. 1996, 129, 1395.

Hg(II) and Pd(II) Derivatives of Terephthaldehyde
Organometallics, Vol. 16, No. 24, 1997 5277
Sch em e 4
Sch em e 5
of both formyl groups was used. It seems reasonable
to assume that MnO4 preferentially attacks the car-
formyl group at the 2 position was selectively trans-
formed into the corresponding imine group, giving
-
bonyl carbon of the less hindered 5-CHO group in the
case of the palladium(II) complexes,40 while the HgCl
group in 1 does not seem to be sufficiently bulky to
prevent the oxidation of the 2-CHO substituent. The
preferential oxidation of the 5-CHO group in 1 when
1:0.67 molar ratio of 1:KMnO4 was used also points to
the same conclusion. It was not possible to isolate any
product from the reaction of complex 4 with KMnO4
because it does not survive the reaction conditions.
Rea ction s w ith Am in es. When complex 3 is re-
acted with p-toluidine in boiling toluene, an ill-defined
mixture is obtained. However, addition of sodium
perchlorate results in the formation of the cyclometa-
complexes [Pd{C6H3(CHdNR)-2-(CHO)-5}(tmeda)]X (X
) ClO4, R ) C6H4Bu-4 (12b), C6H4NH2-4 (12c); X ) CF3-
SO3, R ) C6H4NH2-4 (12c′)) (Scheme 5). This regio-
selectivity is without a doubt due to the above-
mentioned chelating effect and, for this reason, is
opposite to that observed in the previous oxidation
reactions.
Complexes 12 can be reacted with other amines in
order to prepare palladated “mixed” Schiff bases. Thus,
12b reacts with 1,4-phenylenediamine to give 13 (Scheme
5). Despite the fact that 13 seems to be spectroscopi-
cally pure, the carbon analysis is low (see Experimental
Section). We do not know if this is due to combustion
problems in the analyzer or to the presence of an
impurity not detected by NMR.
lated cationic compound [Pd{C6H3(CHdNTo)-2-
(CHdNTo)-5}(tmeda)](ClO4) (11a ) (Scheme 5). It is
reasonable to assume that the replacement of the chloro
ligand by the labile perchlorate anion favors the coor-
dination of the nitrogen atom of the imine group and
that this chelating effect is responsible for the formation
Cyclopalladated benzylideneimines of aromatic amines
are among the best studied cyclopalladated complexes.
Cyclopalladation41,42 is the most frequently used process
to prepare these complexes,43-48 although the exchange
of 11a . Compounds [Pd{C6H3(CHdNR)-2-(CHdNR)-
5}(N-N)]ClO4 (R ) C6H4Bun-4, N-N ) tmeda (11b), bpy
(11′b)) were similarly prepared. A slightly different
(41) Ryabov, A. D. Chem. Rev. 1990, 90, 403.
(42) Omae, I. Organometallic Intramolecular-Coordination Com-
pounds; Elsevier: Amsterdam, The Netherlands, 1986.
(43) Albert, J .; Granell, J .; Moragas, R.; Fontbardia, M.; Solans, X.
J . Organomet. Chem. 1996, 522, 59.
procedure was used for the synthesis of [Pd-
{C6H3(CHdNR)-2-(CHdNR)-5}(N-N)]ClO4 (R ) C6H4-
NH2-4, N-N ) tmeda (11c), bpy (11′c)) in that the
reaction was carried out in acetonitrile using an excess
of the amine. When the same procedure was followed
using a 1:1 palladium(II) to amine molar ratio, the
(44) Vila, J . M.; Gayoso, M.; Pereira, T.; Lopez, M.; Alonso, G.;
Fernandez, J . J . J . Organomet. Chem. 1993, 445, 287.
(45) Albert, J .; Granell, J .; Sales, J .; Fontbardia, M.; Solans, X.
Organometallics 1995, 14, 1393.
(46) Vila, J . M.; Gayoso, M.; Pereira, T.; Torres, M. L.; Fernandez,
J . J .; Fernandez, A.; Ortigueira, J . M. J . Organomet. Chem. 1996, 506,
165.
(47) Basuli, F.; Chattopadhyay, P.; Sinha, C. Polyhedron 1996, 15,
2439.
(48) Lopez, C.; Bosque, R. J . Organomet. Chem. 1996, 524, 247.
(40) House, H. O. Modern Synthetic Reactions, 2nd ed.;
Benjamin/Cummings: Reading, MA, 1972.

5278 Organometallics, Vol. 16, No. 24, 1997
Vicente et al.
of cyclopalladated ligands has also been utilized.49,50
Cyclopalladated derivatives of diimines of terephthal-
dehyde are rare.44,51 Reaction of terephthaldehyde bis-
(cyclohexylimine) with palladium(II) acetate failed to
give the corresponding cyclopalladated complex, and
only the product resulting from the partial hydrolysis
Sch em e 6
[Pd{C6H3(CHdNC6H11)-2-(CHO)-5}(µ-O2CMe)]2 could
be isolated. Derivatives of the diimine were isolated by
reacting this and similar derivatives with cyclohexyl-
amine. The reaction of [Pd{C6H3(CHdNC6H11)-2-(CHO)-
5}(µ-Cl)]2 with 2,4,6-trimethylaniline led to the only
precedent of our mixed complex 13.44 While this
manuscript was in preparation, the synthesis of a
dipalladated derivative of terephthaldehyde bis(cyclo-
hexylimine) has been reported via oxidative addition of
the 2,5-dichloro derivative with [Pd2(dba)3] (dba )
dibenzylidene acetone).51
Rea ction s w ith Hyd r oxyla m in es. The mercurial
1 reacts with hydroxylamine to give the mercuriated
oxime [HgCl{C6H3(CHdNOH)2-2,5}] (14). It can be
used as transmetalating agent with (Me4N)2[Pd2Cl6] to
give the cyclopalladated complex [Pd{C6H3(CHdNOH)-
2-(CHdNOH)-5}(µ-Cl)]2 (15) (Scheme 6). This insoluble
material reacts with [(Ph3P)2N]Cl to give the soluble
anionic complex [(Ph3P)2N][Pd{C6H3(CHdNOH)-2-
(CHdNOH)-5}Cl2] (16) and with Tl(CF3SO3) to give the
compound [Pd{C6H3(CHdNOH)-2-(CHdNOH)-5}(µ-O3-
SCF3)]2 (17), which, in turn, reacts with bpy yielding
[Pd{C6H3(CHdNOH)-2-(CHdNOH)-5}(bpy)]CF3SO3 (18).
We have tried to prepare similar compounds by
reacting the palladium(II) complexes 3 or 3′ with NH2-
OH, but we could not separate the mixtures obtained.
However, complex 3 reacts cleanly with NH2OMe to give
the expected complex [Pd{C6H3(CHdNOMe)-2-
(CHdNOMe)-5}(tmeda)]ClO4 (19) (Scheme 6).
are aware, complexes 15-19 are the first cyclopalla-
dated oximes derived from terephthaldehyde, compound
19 being the first cyclometalated O-Me oxime and 14
the first mercuriated aryloxime.
Dip a lla d a tion of Ter ep h th a ld eh yd e. By reacting
the diimine C6H4(CHdNTo)2-1,4 with palladium(II)
acetate in boiling toluene (molar ratio 1:2), we obtained
an insoluble material whose analytical data suggested
Palladation of oximes has been achieved by
cyclopalladation,52-58 ligand exchange reactions,59 or
transmetalation reactions using organotin oximes.60
Therefore, we have discovered two new methods for the
synthesis of cyclopalladated aryl oximes: (i) transmeta-
lation using mercury derivatives and (ii) condensation
of oximes into orthoformylarylpalladium(II) complexes.
Cyclopalladated aryl oximes have found interesting
applications in organic synthesis.58,61-63 As far as we
it to be the dipalladated imine [Pd{C6H2(CHdNTo)-2-
{Pd(µ-OAc)}-4-(CHdNTo)-5}(µ-OAc)]n (20) (Scheme 7).
The same compound can also be obtained when the
reaction is carried out using a 1:1 molar ratio. Double
(49) Ryabov, A. D.; Yatsimirsky, A. K. Inorg. Chem. 1984, 23, 789.
(50) Granell, J .; Sainz, D.; Sales, J .; Solans, X.; Font-Altaba, M. J .
Chem. Soc., Dalton Trans. 1986, 1785.
(51) Vila, J . M.; Gayoso, M.; Pereira, M. T.; Torres, M. L.; Fernandez,
J . J .; Fernandez, A.; Ortigueira, J . M. Z. Anorg. Allg. Chem. 1997, 623,
844.
(52) Onoue, H.; Minami, K.; Nakagawa, K. Bull. Chem. Soc. J pn.
1970, 43, 3480; Chem. Abstr. 1971, 74, 53979k.
(53) Nielson, A. J . J . Chem. Soc., Dalton Trans. 1981, 205.
(54) Phillips, I. G.; Steel, P. J . J . Organomet. Chem. 1991, 410, 247.
(55) Constable, A. G.; McDonald, W. S.; Sawkins, L. C.; Shaw, B. L.
J . Chem. Soc., Dalton Trans. 1980, 1992.
palladation on
a
single phenyl ring is rarely
encountered.54,64-66 Attempts to dipalladate 1,3- and
1,4-C6H4(CHdNCy)2 resulted in single palladation and
hydrolysis of the meta imine group, probably due to the
solvent used (acetic acid).44,46 By refluxing a mixture
(56) Grigor, B. A.; Nielson, A. J . J . Organomet. Chem. 1977, 132,
439.
(57) Carr, K.; Sutherland, J . K. J . Chem. Soc., Chem. Commun.
1984, 1227.
(61) Baldwin, J . E.; Na´jera, C.; Yus, M. J . Chem. Soc., Chem.
Commun. 1985, 126.
(62) Yatsimirsky, A. K.; Kazankov, G. M.; Ryabov, A. D. J . Chem.
Soc., Perkin Trans. 2 1992, 1295.
(58) Baldwin, J . E.; J ones, R. H.; Na´jera, C.; Yus, M. Tetrahedron
1985, 41, 699.
(59) Ryabov, A. D.; Kazankov, G. M.; Yatsimirsky, A. K.; Kuzmina,
L. G.; Burtseva, O. Y.; Dvortsova, N. V.; Polyakov, V. A. Inorg. Chem.
1992, 31, 3083.
(60) Nishiyama, H.; Matsumoto, M.; Matsumoto, T.; Miura, R.; Itoh,
K. Organometallics 1985, 4, 1911.
(63) Krooglyak, E. V.; Kazankov, G. M.; Kurzeev, S. A.; Polyakov,
V. A.; Semenov, A. N.; Ryabov, A. D. Inorg. Chem. 1996, 35, 4804.
(64) Chakladar, S.; Paul, P.; Mukherjee, A. K.; Dutta, S. K.; Nanda,
K. K.; Podder, D.; Nag, K. J . Chem. Soc., Dalton Trans. 1992, 3119.
(65) Chakladar, S.; Paul, P.; Venkatsubramanian, K.; Nag, K. J .
Chem. Soc., Dalton Trans. 1991, 2669.
(66) Chakladar, S.; Paul, P.; Nag, K. Polyhedron 1991, 10, 1513.

Hg(II) and Pd(II) Derivatives of Terephthaldehyde
Organometallics, Vol. 16, No. 24, 1997 5279
Sch em e 7
F igu r e 1. ORTEP plot of 9 with the labeling scheme (50%
probability ellipsoids).
of 1,3-C6H4(CHdNR)2 (R ) Et, Bu, C8H17, benzyl) and
palladium(II) acetate in chloroform, dipalladated com-
plexes have been isolated.65
The nature of complex 20 requires it to have some
degree of polymerization, which accounts for its insolu-
bility. In the above-mentioned derivative of 1,3-C6H4-
[CHdN(C8H17)]2, a molecular mass determination in
solution showed its tetranuclear nature.65 Due to the
extreme insolubility of 20, we were not able to prepare
any derivative by reacting it with bpy or NaBr and
pyridine. However, we did manage to hydrolyze it by
reacting it with KBr and bpy (1:10:2) in the presence of
an excess of acetic acid in a 5:1 acetone/water mixture.
Under these conditions, the diformyl dipalladated com-
pound [C6H2{PdBr(bpy)}2-1,4-(CHO)2-2,5] (21) is ob-
tained. Nevertheless, its insolubility has prevented
complete purification. We believe that this compound
is slightly contaminated with some metallic palladium-
(II), as found in similar complexes.51 However, the
reaction of 21 with PPh3 and KCF3SO3 (1:2:2) affords
the more soluble [C6H2{Pd(PPh3)(bpy)}2-1,4-(CHO)2-
2,5](CF3SO3)2 (22), which can be isolated as an analyti-
cally pure compound (Scheme 7). These compounds are
the first reported double-palladated arenes having
formyl functions. The hydrolytic process used for their
formation allows further applications to other similar
cases.
Str u ctu r a l Stu d ies. Cr ysta l Str u ctu r es of Com -
p lexes 9‚Me2CO‚1.5MeOH, 10‚2CH2Cl2, a n d 12c′.
Figures 1-3 show the structures of these complexes and
Tables 1-4 give the crystal data and selected bond
lengths and angles. The three complexes show the
expected square-planar geometry at the metal center,
but in 9‚Me2CO‚1.5MeOH and 10‚2CH2Cl2 only slight
distortions are observed but in 12c′ the distortion is
much greater due to the small bite angle of the five-
membered C-N chelate ring (78.5(3)°) and of the tmeda
F igu r e 2. ORTEP plot of 10 showing interactions with a
dichloromethane molecule (50% probability ellipsoids).
ligand (83.38(12)°). The greater trans influence of the
aryl ligand compared to that of the N-imine ligand in
12c′ causes the Pd-N(3) bond (2.190(3) Å) to be longer
than that of Pd-N(4) (2.112(3) Å).
In spite of the great similarity of complexes 9‚Me2-
CO‚1.5MeOH and 10‚2CH2Cl2, the Pd-Cl and Pd-P
bond distances are significantly different, although
Pd-C distances are essentially identical (2 Å). The Pd-
Cl bond distance is shorter in 10‚2CH2Cl2 (2.3917(8) Å)
than in 9‚Me2CO‚1.5MeOH (2.4018(8) Å), while the
Pd-P bond lengths are longer in 10‚2CH2Cl2 (2.3482(5)
Å) than in 9‚Me2CO‚1.5MeOH (2.3205(9), 2.3272(9) Å).
It is not reasonable to assume that the slightly different
nature of the aryl groups is responsible for the observed
differences. In our opinion, such features are due to the

5280 Organometallics, Vol. 16, No. 24, 1997
Vicente et al.
Ta ble 2. Selected Bon d Len gth s (Å), Bon d An gles (d eg), a n d In ter m olecu la r Con ta cts (Å, d eg) for
9‚Me2CO‚1.5MeOH
Bond Lengths
Pd-C(1)
2.000(3)
2.3272(9)
1.208(4)
1.209(4)
1.489(5)
Pd-P(2)
Pd-Cl
O(2)-C(7)
O(4)-C(8)
C(5)-C(8)
2.3205(9)
2.4018(8)
1.332(4)
1.325(4)
1.487(5)
Pd-P(1)
O(1)-C(7)
O(3)-C(8)
C(2)-C(7)
Bond Angles
C(1)-Pd-P(2)
P(2)-Pd-P(1)
P(2)-Pd-Cl
C(6)-C(1)-C(2)
O(1)-C(7)-C(2)
O(3)-C(8)-O(4)
O(4)-C(8)-C(5)
89.66(9)
175.41(3)
90.83(3)
118.0(3)
125.2(3)
122.8(3)
114.0(3)
C(1)-Pd-P(1)
C(1)-Pd-Cl
87.68(9)
174.27(9)
91.44(3)
122.1(3)
112.7(3)
123.2(3)
P(1)-Pd-Cl
O(1)-C(7)-O(2)
O(2)-C(7)-C(2)
O(3)-C(8)-C(5)
Intermolecular Contactsa
O(7)‚‚‚H(04)
O(5)‚‚‚H(02)
Cl#1‚‚‚H(05)
1.965(19)
1.846(7)
2.439(26)
O(7)‚‚‚O(4)
O(5)‚‚‚O(2)
O(5)‚‚‚Cl#1
2.757(4)
2.627(4)
3.164 (3)
O(7)‚‚‚H(04)-O(4)
O(5)‚‚‚H(02)-O(2)
O(5)-H(05)‚‚‚Cl#1
156(4)
154(1)
145(4)
a
Symmetry transformations: #1 -x + 1, y, z.
Ta ble 4. Selected Bon d Len gth s (Å) a n d An gles
(d eg) for 12c′
Bond Lengths
Pd-C(1)
2.014(4)
2.104(10)
2.190(3)
1.476(5)
1.351(11)
1.370(9)
1.415(10)
Pd-N(1)
2.033(9)
2.112(3)
1.209(5)
1.218(9)
1.448(12)
1.419(13)
Pd-N(1′)
Pd-N(3)
Pd-N(4)
O(1)-C(8)
C(7)-N(1)
N(1)-C(11)
N(1′)-C(11′)
C(5)-C(8)
C(7)-N(1′)
N(2)-C(14)
N(2′)-C(14′)
Bond Angles
C(1)-Pd-N(1)
C(1)-Pd-N(4)
N(1′)-Pd-N(3)
C(2)-C(1)-Pd
78.5(3)
97.55(13) N(1)-Pd-N(3)
96.1(3)
C(1)-Pd-N(1′)
83.0(3)
100.6(3)
83.38(12)
114.3(3)
N(4)-Pd-N(3)
C(1)-C(2)-C(7)
111.6(3)
N(1)-C(7)-C(2) 115.9(5)
N(1′)-C(7)-C(2) 121.5(5)
O(1)-C(8)-C(5)
C(7)-N(1′)-Pd
125.3(4)
107.8(5)
C(7)-N(1)-Pd
118.6(5)
Figures 2 and 4). A similar polymerization, but involv-
ing [Pt]Cl‚‚‚HOAr or [Pt]Cl‚‚‚HC2Ar, has recently been
found in the structure of some arylplatinum com-
plexes.67,68 In 9‚Me2CO‚1.5MeOH, dimers are as-
sembled through four hydrogen bonds established by
two bridging molecules of MeOH. Each MeOH molecule
acts as a hydrogen bond donor, MeOH‚‚‚Cl-Pd (O(5)‚‚‚
Cl, 3.164(3) Å; Cl‚‚‚HO(5), 2.439(26) Å; O(5)-OH(5)‚‚‚
Cl, 145(4)°; see Figure 5) and acceptor C(O)OH‚‚‚
O(H)Me (O(5)‚‚‚O(2), 2.627(4) Å; O(5)‚‚‚HO(2), 1.846(7)
Å; O(5)-OH(2)‚‚‚O(2), 153.99(1.24)°; see Figure 5).
Additionally, two molecules of acetone are hydrogen
bonded to the two remaining CO2H groups of the dimer
(O(7)‚‚‚O(4), 2.757(4) Å; O(7)‚‚‚HO(4), 1.965(19) Å; O(7)-
OH(4)‚‚‚O(4), 156.72(4.53)°; see Figure 5).
F igu r e 3. ORTEP plot of the anion of compound 12c′ with
the labeling scheme (50% probability ellipsoids).
Ta ble 3. Selected Bon d Len gth s (Å), Bon d An gles
(d eg), a n d In ter m olecu la r Con ta cts for 10‚2CH2Cl2
Bond Lengths
Pd-C(11)
Pd-Cl(1)
O(2)-C(17)
C(13)-C(17)
1.999(3)
2.3917(8)
1.204(4)
1.499(5)
Pd-P
2.3482(5)
1.316(5)
1.205(4)
1.483(5)
O(1)-C(17)
O(3)-C(18)
C(16)-C(18)
Bond Angles
The one-dimensional polymers in 10‚2CH2Cl2 are
assembled in parallel, giving a two-dimensional network
in which the metal and the aryl and chloro ligands as
well as the CCl2 moieties of the CH2Cl2 molecules are
coplanar (see Figure 6). One of the two CH2Cl2 mol-
ecules associated to each molecule of 10 shows a close
C-Cl‚‚‚OdC(OH)R contact (Cl(2)-O(2), 3.042(3) Å; the
sum of the van der Waals radii of Cl and O is 3.20 Å),
while the other CH2Cl2 molecule does not show such an
interaction (see Figure 4). A search of the Cambridge
C(11)-Pd-P
90.42(2)
176.80(10) P-Pd-Cl(1)
124.6(4)
P-Pd-P#1
176.19(4)
89.48(2)
C(11)-Pd-Cl(1)
O(2)-C(17)-O(1)
O(2)-C(17)-C(13) 123.1(4)
O(3)-C(18)-C(16) 126.4(4)
O(1)-C(17)-C(13) 112.3(3)
Intermolecular Contactsa
O(2)‚‚‚Cl(2)
O(1)‚‚‚Cl1#2
3.042(3)
3.120 (3)
Cl1#2‚‚‚H(01)
O(1)-H(01)‚‚‚Cl1#2
2.518 (40)
168(4)
a
Symmetry transformations: #1 -x + 1, y, z; #2 -x + 1, -y +
2, z + 0.5.
different type of intermolecular interactions. In 10‚
2CH2Cl2, an intermolecular self-assembly is established
through hydrogen bonds between the carboxylic group
and the chloro ligand (O(1)‚‚‚Cl(#1), 3.120(3) Å; Cl-
(#1)‚‚‚H(1), 2.518(40) Å; O(1)-H(1)‚‚‚Cl(#1), 168(5)°; see
(67) J ames, S. L.; Verspui, G.; Spek, A. L.; Vankoten, G. Chem.
Commun. 1996, 1309.
(68) Davies, P. J .; Veldman, N.; Grove, D. M.; Spek, A. L.; Lutz, B.
T. G.; van Koten, G. Angew. Chem., Int. Ed. Engl. 1996, 35, 1959.

Hg(II) and Pd(II) Derivatives of Terephthaldehyde
Organometallics, Vol. 16, No. 24, 1997 5281
the region 8.76-8 ppm are observed. These data allow
us to assign the resonance at 10 ppm in 12 to the 5-CHO
group and those in the region 8.76-8 ppm to the 2- and
5-CHdNR protons. The resonances assignable to the
CHO protons of mercurials 1 and 2 (see Scheme 1)
appear at 10.19 and 10.09 and 10.43 and 10.18 ppm,
respectively. These values are similar to that of tere-
phthaldehyde (10.14 ppm) and that of the 5-CHO group
in 12 (see Scheme 5). However, the palladium(II)
complexes 3, 3′, and 4 (see Scheme 2) exhibit, in addition
to the expected 10 ppm resonance due to the 5-CHO
proton, signals at 11.23, 11.21, and 9.47 ppm, respec-
tively. Therefore, contrary to the HgCl and HgC6H3-
(CHO)2-2,5 groups, the PdCl(N-N) and PdCl(PPh3)2
moieties exert some influence on the chemical shift of
the 2-CHO proton, although the PdCl(N-N) group in 3
and 3′ deshields and the PdCl(PPh3)2 group in 4 slightly
shields this proton. Accordingly, the resonances at
11.24 and 11.08 in 5 and 5′ (see Scheme 3), at 10.95
ppm in 21 (see Scheme 7), and at 9.77 ppm in 10 (see
Scheme 4) must be assigned to the 2-CHO proton.
Furthermore, addition of PPh3 into a solution of complex
1
5 gives complex 10 (by H and 31P NMR). These data
prove that the oxidation of complexes 3 and 3′ took place
at the 5-CHO group. Complexes 6 (see Scheme 3) and
22 (see Scheme 7) having the Pd(PPh3)(N-N) substituent
show the 2-CHO resonance at 10.12 and 9.65 ppm,
respectively.
Compounds 3, 5, and 19 show four signals corre-
sponding to the NMe2 groups of the tmeda ligand
because the rotation around the aryl carbon-palladium
bond is restricted at room temperature on the NMR time
scale; this behavior is quite commonly observed.4,72
F igu r e 4. Packing diagram of compound 10 showing the
hydrogen bonds and O‚‚‚Cl interactions within the mirror
plane. Triphenylphosphine ligands have been omitted for
clarity.
Complex 17 could be formulated as a dimer, as done
for complex 15 and by analogy to similar cyclopalladated
dimers. However, given the low coordinating ability of
the triflato group, an alternative formulation could be
the coordination of the oxygen or nitrogen atoms of the
oxime groups giving oligomers or polymers in the solid
state. Unfortunately, attempts to grow single crystals
suitable for an X-ray crystallographic study have so far
failed. This complex shows a value for the molar
Structural Database reveals that C(sp3)-Cl‚‚‚OdC close
contacts with a C(sp3)-Cl‚‚‚OdC distance less than 3.20
Å are present in 101 molecules (excluding those in which
the CO group is a carbonyl ligand). The mean Cl‚‚‚O
distance is 3.085.69-71
1
NMR Sp ectr a . We have used the H NMR spectral
resonances corresponding to the formyl groups (comple-
mented with the above X-ray data) as a tool for propos-
ing the structures of the compounds. Complexes 12,
whose structure must reasonably be that found by X-ray
crystallography for 12c′ (see Scheme 5), show two
resonances at 10 and 8.44-8.11 ppm. The first disap-
pears in complexes 11 and 13, while two resonances in
conductivity in an acetone solution (62 Ω-1 cm2 mol-1
)
that is too low for an ionic species but too high for a
neutral one. It indicates that the solvent partially
displaces the triflato anion, giving rise to the establish-
ment of an equilibrium between neutral and cationic
species.
F igu r e 5. Hydrogen bond interactions between 9, MeOH, and Me2CO. The atoms involved have been labeled. Hydrogen
atoms of the phenyl groups have been omitted for clarity.

5282 Organometallics, Vol. 16, No. 24, 1997
Vicente et al.
F igu r e 6. A view of the crystal packing of compound 10 along the c axis. Phenyl groups of the phosphine ligands have
been omitted for clarity.
Con clu sion s
curiated and -palladated oximes have also been obtained
by a condensation reaction for the former and by a
transmetalation reaction for the latter. The X-ray
crystal structures show interesting self-assembled fea-
tures. Finally, we designed a synthetic procedure which
permits one to isolate dipalladated terephthaldehyde.
All of these functionalized aryl complexes open ways to
prepare, through other organic reactions, new types of
complexes.
We have developed a process which permits the
mercuriation of the strongly deactivated terephthalde-
hyde to give (2,5-diformylphenyl)mercurials. These
complexes have been used as transmetalating agents
for the synthesis of new arylpalladium(II) complexes
containing this functionalized aryl ligand. We have
exploited the reactivity of the formyl substituents in
order to gain access to new functionalized aryl com-
plexes. Thus, oxidation with KMnO4 takes place selec-
tively at the less hindered formyl group or at both
groups, depending on the metal and the reaction condi-
tions. Reactions with amines can be controlled in order
to permit the formation of stable orthopalladated mono-
and di(homo and hetero)imine complexes. Ortho-mer-
Ack n ow led gm en t. We thank Direccio´n General de
Investigacio´n Cient´ıfica y Te´cnica (PB92-0982-C) for
financial support. B.R. and M.C.R.A. are grateful to the
Ministerio de Educacio´n y Cultura (Spain) for a grant
and a contract, respectively. F.-S.H. is grateful to
Fundacio´n Cultural CAM for a grant.
(69) McKague, A. B.; Rettig, S. J .; Trotter, J . Acta Crystallogr. 1988,
C44, 892.
(70) Senge, M. O.; Ruhlandt-Senge, K.; Regli, K. J .; Smith, K. M. J .
Chem. Soc., Dalton Trans. 1993, 3519.
(71) Arora, S. K.; Bates, R. B.; Grady, R. A.; Delfel, N. E. J . Am.
Chem. Soc. 1975, 97, 5752.
(72) Brown, J . M.; Perez-Torrente, J . J .; Alcock, N. W.; Clase, H. J .
Organometallics 1995, 14, 207.
Su p p or tin g In for m a tion Ava ila ble: X-ray crystallo-
graphic files, in CIF format, for compounds 9, 10, and 12c′
are available on the Internet only. Access information is given
on any current masthead page.
OM970583U