Contrasting Behavior of Bis[2-(4,4-dimethyl-2-oxazolinyl)phenyl] Chalcogenides (Se/Te) toward Mercuric Chloride: Facile Cleavage of the Te-C Bond

Article abstract of DOI:10.1021/om034222s

The reactions of R₂Se (3) and R₂Te (4) (R = 2-(4,4-dimethyl-2-oxazolinyl)phenyl) with HgCl₂ and Pd(COD)Cl ₂ are described. The reaction of selenoether 3 with HgCl₂ affords the expected complex R₂

Full text of DOI:10.1021/om034222s

Organometallics 2003, 22, 5473-5477
5473
Con tr a stin g Beh a vior of
Bis[2-(4,4-d im eth yl-2-oxa zolin yl)p h en yl] Ch a lcogen id es
(Se/Te) tow a r d Mer cu r ic Ch lor id e: F a cile Clea va ge of
th e Te-C Bon d
Sandeep D. Apte,† Sanjio S. Zade,† Harkesh B. Singh,*,† and Ray J . Butcher‡
Department of Chemistry, Indian Institute of Technology, Bombay, Powai, Mumbai 400076,
India, and Department of Chemistry, Howard University, Washington, D.C. 20059
Received October 9, 2003
The reactions of R2Se (3) and R2Te (4) (R ) 2-(4,4-dimethyl-2-oxazolinyl)phenyl) with HgCl2
and Pd(COD)Cl2 are described. The reaction of selenoether 3 with HgCl2 affords the expected
complex R2SeHgCl2 (5), which is stable in solution. In contrast, the analogous tellurium
complex R2TeHgCl2 (6) undergoes slow dismutation in chlorinated solvents to give the
fragments RTeCl (7) and RHgCl (8).
Sch em e 1
In tr od u ction
The coordination chemistry of ligands containing
heavier chalcogens (Se/Te) is an area of growing inter-
est.1 Increased interest in this area is due to the
application of these ligands in (i) isolation of single-
source precursors for MOCVD of group 12 chalco-
genides,2 (ii) better σ-donor capacity of Se/Te ligands
compared to the lighter group 16 congeners,1 and (iii)
easy use in stoichiometric/catalytic organic synthesis.3
Recently Uemura and co-workers reported a palladium-
catalyzed Fujiwara-Heck cross-coupling reaction be-
tween organic tellurides and alkenes (Scheme 1).4
The key step of this coupling reaction was proposed
to be the migration of an organic moiety from Te to Pd
(transmetalation) in organic telluride-PdCl2 complexes
to afford the organopalladium species (eq 1). Such
chemistry were discovered for the first time by McWhin-
nie and co-workers.5 The reaction of (2-(2-pyridyl)-
phenyl)(3-ethoxyphenyl)tellurium (1; RR′Te) with HgCl2
[(R2Te)PdZ2]2 or (R2Te)2PdZ2 f RPdZ + RTeZ
(1)
reverse transmetalation reactions in organotellurium
* To whom correspondence should be addressed. E-mail: chhbsia@
chem.iitb.ac.in.
† Indian Institute of Technology.
afforded [R′HgCl‚2RTeCl2]. In a series of papers,
McWhinnie and co-workers have established the lability
of organic groups from tellurium on reaction with metal
compounds.6 More recently, we have reported a facile
C-Te bond cleavage/transmetalation in the reaction of
‡ Howard University.
(1) (a) Hope, E. G.; Levason, W. Coord. Chem. Rev. 1993, 122, 109
and references therein. (b) Singh, A. K.; Sharma, S. Coord. Chem. Rev.
2000, 209, 49 and references therein. (c) Levason, W.; Orchard, S. D.;
Reid, G. Coord. Chem. Rev. 2002, 225, 159.
(2) (a) Bonasia, P. J .; Arnold, J . J . Organomet. Chem. 1993, 449,
147. (b) Cheng, Y.; Emge, T. J .; Brennan, J . G. Inorg. Chem. 1994, 33,
3711. (c) Cheng, Y.; Emge, T. J .; Brennan, J . G. Inorg. Chem. 1996,
35, 3342. (d) Cheng, Y.; Emge, T. J .; Brennan, J . G. Inorg. Chem. 1996,
35, 7339. (e) Mugesh, G.; Singh, H. B.; Butcher, R. J . Inorg. Chem.
1998, 37, 2663. (f) Mugesh, G.; Singh, H. B.; Butcher, R. J . J .
Organomet. Chem. 1999, 577, 243.
7
the 22-membered azamacrocycle 2 with HgCl2 and Pt-
(COD)Cl2.8 The cleavage of the C-Te bond in these
cases is facilitated by the strong NfTe intramolecular
interactions which involve n-σ* orbital interactions and
(3) (a) Wirth, T. Tetrahedron 1999, 55, 1. (b) Wirth, T. Angew.
Chem., Int. Ed. 2000, 39, 3740. (c) Uehlin, L.; Wirth, T. Org. Lett. 2001,
3, 2931. (d) Back, T. G.; Moussa, Z.; Parvez, M. J . Org. Chem. 2002,
67, 499. (e) Tiecco, M.; Testaferri, L.; Santi, C.; Tomassini, C.; Marini,
F.; Bagnoli, L.; Temperini, A. Chem. Eur. J . 2002, 8, 1118. (f) Uehlin,
L.; Fragale, G.; Wirth, T. Chem. Eur. J . 2002, 8, 1125. (g) Iwaoka, M.;
Tomoda, S. J . Chem. Soc., Chem. Commun. 1992, 1165. (h) Fujita, K.;
Iwaoka, M.; Tomoda, S. Chem. Lett. 1994, 923. (i) Wirth, T. Tetrahe-
dron Lett. 1995, 36, 7849. (j) Kaur, R.; Singh, H. B.; Patel, R. P. J .
Chem. Soc., Dalton Trans. 1996, 2719. (k) Fukuzawa, S.; Takahashi,
K.; Kato, H.; Yamazaki, H. J . Org. Chem. 1997, 62, 7711. (l) Wirth,
T.; Ha¨uptli, S.; Leuenberger, M. Tetrahedron: Asymmetry 1998, 9, 547.
(m) Bolm, C.; Kesselgruber, M.; Grenz, A.; Hermanns, N.; Hildebrand,
J . P. New J . Chem. 2001, 13.
(4) (a) Nishibayashi, Y.; Cho, C. S.; Uemura, S. J . Organomet. Chem.
1996, 507, 197. (b) Nishibayashi, Y.; Cho, C. S.; Ohe, K.; Uemura, S.
J . Organomet. Chem. 1996, 526, 335.
(5) (a) Mbogo, S. A.; McWhinnie, W. R.; Lobana, T. S. J . Organomet.
Chem. 1990, 384, 115. (b) Greaves, M. R.; Hamor, T. A.; Howlin, B. J .;
Lobana, T. S.; Mbogo, S. A.; McWhinnie, W. R.; Povey, D. C. J .
Organomet. Chem. 1991, 420, 327.
(6) (a) Mbogo, S. A.; McWhinnie, W. R.; Lobana, T. S. Inorg. Chim.
Acta 1992, 193, 5. (b) Mbogo, S. A.; McWhinnie, W. R.; Lobana, T. S.
Inorg. Chim. Acta 1990, 172, 221. (c) Al-Salim, N. I.; McWhinnie, W.
R. Polyhedron 1989, 8, 2769.
(7) Menon, S. C.; Singh, H. B.; Patel, R. P.; Kulshreshtha, S. K. J .
Chem. Soc., Dalton Trans. 1996, 1203.
10.1021/om034222s CCC: $25.00 © 2003 American Chemical Society
Publication on Web 11/18/2003

5474 Organometallics, Vol. 22, No. 26, 2003
Apte et al.
Sch em e 2
activate the trans C-Te bond. Intramolecular interac-
tions via n-σ* orbital interactions may be a viable
strategy for activating Se-C/Te-C bonds. In this re-
gard, we have begun a systematic study of the cleavage
reactions of series of selenides and tellurides which have
intramolecular interactions. In this paper we report the
reaction of R2E (E ) Se, Te; R ) 2-(4,4-dimethyl-2-
oxazolinyl)phenyl) with Pd(COD)Cl2 and HgCl2.
Resu lts a n d Discu ssion
Compounds 3 and 4 were synthesized by the reported
methods.9 The reaction of 3 with Pd(COD)Cl2 in CH2-
Cl2 afforded a yellow-orange solid which was insoluble
in all common organic solvents. The elemental analysis
indicated the formation of a polymeric complex of the
type (3‚PdCl2)n. However, due to poor solubility, no
further characterization could be carried out. Similarly,
the reaction of 4 with 1 equiv of Pd(COD)Cl2 in CH2Cl2
afforded a yellow powder which was again insoluble in
all organic solvents. Interestingly, slow evaporation of
the reaction mixture afforded dark red crystals with an
insoluble yellow powder. Unfortunately, on standing for
a few days or on recrystallization or precipitation of the
CH2Cl2 solution by hexane, the dark red crystals convert
to the insoluble yellow powder. McWhinnie et al. have
also observed the formation of similar complex systems
in the reaction of 1 with PdCl2.6a
1
F igu r e 1. VT (variable temperature) H NMR of 5.
may take place via five-coordinate mercury (5b) (Scheme
3). The dynamic behavior of the complex has also been
confirmed by VT (variable temperature) 1H NMR stud-
ies (Figure 1). When the temperature is lowered, a
broadening of the signal for methyl protons was ob-
served, which resolved into two singlets at -55 °C. Also,
the singlet corresponding to methylene protons split into
a doublet at this temperature. All signals are found to
be downfield shifted in the 1H NMR spectrum compared
to the free ligand.9
The 77Se NMR spectrum shows a signal at δ 408.2
which is upfield shifted compared to the free ligand (δ
440.3). This may be due to the strong overlap of the
orbitals of Se (where 5s and 4d are unoccupied orbitals)
and mercury (where 6s and 5d orbitals are being filled).
The reaction of selenoether 3 with HgCl2 afforded the
expected complex 5 as a white powder (Scheme 2).
1
The H NMR spectrum of 5 exhibits only one singlet
for the methyl protons and another singlet for the
methylene protons. This indicates resonances corre-
sponding to half of the molecule, suggesting a symmetric
structure for complex 5. However, in the structure by
single-crystal X-ray studies (vide infra), it was found
that the two nitrogen atoms are not equivalent in the
1
solid state. The symmetric H NMR spectrum is prob-
ably due to a fast exchange between Hg‚‚‚N(1) and Hg‚
‚‚N(2) bonds in the coordination sphere around Hg. This
leads to a dynamic equilibrium between the two struc-
tures (5a and 5c) having four-coordinate mercury that
Sch em e 3

Bis[2-(4,4-dimethyl-w-oxazolinyl)phenyl] Chalcogenides
Organometallics, Vol. 22, No. 26, 2003 5475
aromatic protons compared to those of the free ligand
4. Although the elemental analysis and NMR studies
suggest the formation of the 1:1 adduct 6, unfortunately,
the FAB mass spectrum did not show the corresponding
molecular ion peak. The highest peaks correspond to
[(R2Te)2HgCl]+ (m/z 1189 (28%)) and [R2TeHgCl]+ (m/z
713 (39%)).
In CHCl3 or CH2Cl2 solution, interestingly, 6 under-
goes slow dismutation to give the fragments RTeCl (7)
and RHgCl (8)11 (Scheme 4). In an attempt to under-
stand the mechanism of the reaction, when the 125Te
NMR spectrum for the complex 6 was recorded in
DMSO-d6/CDCl3 (1:1) only one signal at 1185 ppm for
the tellurenyl chloride was observed after 10 min. There
was no further change in the spectrum, even after 90
min. Mechanistically, this cleavage can be explained
through electrophilic substitution by mercury at the ipso
carbon of one aromatic ring.12 It leads to the formation
of the σ intermediate, which results in polarization of
the Te-C bond (Te+-C-). Rearomaticization in the
presence of chloride ion generates 7 and 8 with comple-
tion of the aryl migration. The TerN intramolecular
nonbonding interactions may be the additional factor
facilitating the polarization of the Te-C bond. Com-
pounds 7 and 8 were separated by column chromatog-
raphy on silica gel and characterized. Crystals of 7 and
8 for single-crystal X-ray studies were obtained by slow
evaporation of chloroform/hexane (4:1) solutions.
F igu r e 2. Molecular structure of compound 5.
Sch em e 4
1H and 125Te NMR spectra clearly indicate the forma-
tion of compound 7. The 125Te NMR spectrum shows a
sharp signal at 1203 ppm, which is shifted upfield
compared to values reported for related tellurenyl
chlorides having a N‚‚‚Te-Cl bond (1,6-bis(2-(chloro-
telluro)phenyl)-2,5-diazahexa-1,5-diene, 1332.3 ppm;7
2-(chlorotellurenyl)-4′-phenylbenzalaniline, 1355.0 ppm13)
and oxatellurolylium chlorides having an O‚‚‚Te-Cl
bond (3-methyl-5-phenyl-1,2-oxatellurol-1-ium, 1726 ppm;
3,5-diphenyl-1,2-oxatellurol-1-ium, 1692 ppm).14 In the
FAB mass spectrum the base peak corresponds to the
molecular ion peak (m/z 304 (100%)). The peak at m/z
608 corresponds to the dimer which is in good agree-
ment with the X-ray crystal structure data. In RTeCl
(7), the geometry around Te is T-shaped with a strong
Te‚‚‚N interaction (Figure 3). The Te‚‚‚N separation of
2.241(3) Å is much shorter than the sum of van der
Waals radii (3.7 Å).15 The Te-Cl distance (2.5602(10)
Å) is significantly larger that the sum of single-bond
covalent radii (2.36 Å).15 The Te‚‚‚N and Te-Cl bond
distances are comparable to the corresponding distances
of 1,6-bis(2-(chlorotelluro)phenyl)-2,5-diazahexa-1,5-di-
ene (Te‚‚‚N, 2.185(8) Å; Te-Cl, 2.597(3) Å),7 phenyla-
zophenyl(C,N′)tellurium chloride (Te‚‚‚N, 2.210(7) and
X-ray-quality crystals were obtained by slow evapora-
tion of the concentrated chloroform solution. In the solid
state, complex 5 adopts a distorted-tetrahedral geometry
around Hg (Figure 2). The Hg-Se distance (2.7501(17)
Å) is in close agreement with the reported value in the
tetrahedral complexes of Hg with tetraselena crown
ether10a and selenophene.10b The Se-Hg-N angle (82.03-
(10)°) is much smaller and comparable to the Se-Hg-
Se bond angle in the tetraselena crown ether complex
with mercury.
Reaction of 4 with HgCl2 in a 1:1 stoichiometric
amount also afforded the white complex 6 (Scheme 4),
which was sparingly soluble in all organic solvents
except DMSO. Complex 6 was characterized by 1H, 13C,
and 125Te NMR and mass spectrometric techniques. The
1H NMR spectrum of 6 shows an upfield shift for methyl
protons but downfield shifts for methylene protons and
(11) (a) Bonnardel, P.-A.; Parish, R. V. J . Organomet. Chem. 1996,
515, 221. (b) Bonnardel, P.-A.; Parish, R. V.; Pritchard, R. G. J . Chem.
Soc., Dalton Trans. 1996, 3185.
(12) (a) Detty, M. R.; Murray, B. J .; Smith, D. L.; Zumbulyadis, N.
J . Am. Chem. Soc. 1983, 105, 875. (b) Piette, J .-N.; Thibaut, P.; Renson,
M. Tetrahedron 1978, 34, 655.
(13) (a) Minkin, V. I.; Sadekov, I. D.; Maksimenko, A. A.; Kompan,
O. E. J . Organomet. Chem. 1991, 402, 331. (b) Minkin, V. I.; Maksi-
menko, A. A.; Mehrotra, G. K.; Maslakov, A. G.; Kompan, O. E.;
Sadekov, I. D. J . Organomet. Chem. 1991, 402, 331.
(14) Detty, M. R.; Lenhart, W. C. Organometallics 1989, 8, 866.
(15) Pauling, L. The Nature of the Chemical Bond, 3rd ed.; Cornell
University Press: Ithaca, NY, 1960.
(8) Menon, S. C.; Panda, A.; Singh, H. B.; Butcher, R. J . Chem.
Commun. 2000, 143.
(9) Apte, S. D.; Singh, H. B.; Butcher, R. J . J . Chem. Res., Synop.
2000, 160; J . Chem. Res., Miniprint 2000, 0559.
(10) (a) Mazouz, A.; Meunier, P.; Kubicki, M. M.; Hanquet, B.;
Amardeil, R.; Bornet, C.; Zahidi, A. J . Chem. Soc., Dalton Trans. 1997,
1043. (b) Stalhandske, C.; Zintl, F. Acta Crystallogr., Sect. C 1988, 44,
253.

5476 Organometallics, Vol. 22, No. 26, 2003
Apte et al.
F igu r e 3. Molecular structure of compound 7.
F igu r e 4. Molecular structure of compound 8.
2.23(2) Å; Te-Cl, 2.533(3) and 2.552(8) Å),16 (2-(2-
pyridyl)phenyl)tellurium chloride (Te‚‚‚N, 2.205(11) Å;
Te-Cl, 2.606(11) Å),5b,17 and 2-(chlorotelluronyl)-4′-
methylbenzalaniline (Te‚‚‚N, 2.218(6) and 2.239(6) Å;
Te-Cl, 2.582(2) and 2.553(2) Å).13 The Te-Cl distance
is, however, longer than the related distance of 3-phen-
yl-5-(4-methoxyphenyl)-1,2-oxatellurol-1-ium chloride,
where tellurium is intramolecularly coordinated with
the oxygen atom by a secondary interaction.12 The
intermolecular distance (3.642 Å) between Te and
Cl(A) is considerably shorter than the sum of the van
der Waals radii (4.0 Å), indicating a secondary interac-
tion between the molecules.
The unit cell of the molecular structure of RHgCl (8)
contains two nonsymmetric equivalent molecules. No
significant difference between these two molecules was
observed. The coordination geometry around Hg is
T-shaped, having a weak bonding interaction with
nitrogen. Hg-N, Hg-C, and Hg-Cl distances are in
close agreement with those reported by Nelson et al.18
(Figure 4) for related compounds.
standards. Elemental analyses were performed on a Carlo-
Erba Model 1106 elemental analyzer. IR spectra were recorded
as KBr pellets on a Nicolet Impact 400 FTIR spectrometer.
Fast atom bombardment (FAB) mass spectra were recorded
at room temperature on a J EOL SX 102 DA-6000 mass
spectrometer/data system using xenon (6 kV, 10mV) as a
bombarding gas.
Syn th eses. [C6H4(C5H8NO)]2SeHgCl2 (5). To a stirred
solution of selenoether 3 (0.426 g, 1 mmol) in dry CH2Cl2 (20
mL) was added a solution of HgCl2 (0.298 g, 1.1 mmol) in
acetone (5 mL). Stirring was continued for 0.5 h. The reaction
mixture was evaporated to give a white powder. This was
dissolved in CHCl3 (50 mL), and the solution was washed
repeatedly with water to remove excess HgCl2; the chloroform
layer was dried over sodium sulfate and evaporated under
vacuum to give a white powder. This was crystallized by slow
evaporation of a concentrated chloroform solution (0.67 g,
98%). Mp: 196-198 °C. 1H NMR (CDCl3): δ 8.00-7.97 (m,
2H), 7.51-7.40 (m, 6H), 4.11 (s, 4H), 1.27 (s, 12H). 13C NMR
(CDCl3): δ 27.5, 68.7, 79.2, 127.9, 128.9, 131.0, 131.4, 132.1,
133.3, 162.6. 77Se NMR (CDCl3): δ 408.2. MS: m/z 713 (M+
+
Me, 34%), 304 (100%), 412 (10%), 478 (31%). IR (KBr, cm-1):
1637 (νCdN). Anal. Calcd for C22H24Cl2HgN2O2Se: C, 37.82; H,
3.46; N, 4.00. Found: C, 37.35; H, 3.43; N, 3.78.
In summary, the C-Se bond, even after activation,
does not undergo a cleavage reaction. In contrast, the
acyclic R2Te cleaves under very mild conditions. To the
best of our knowledge, this is the first structural report
of a mercury complex with an (Se, N) type hybrid
selenoether ligand and of the isolation and structural
characterization of both of the cleaved products in the
reaction of an (N, Te, N) type telluroether with HgCl2.
[C6H4(C5H8NO)]2TeHgCl2 (6). To a stirred solution of
telluroether 4 (0.476 g, 1 mmol) in methanol (20 mL) was
added HgCl2 (0.298 g, 1.1 mmol). A white precipitate was
obtained immediately. After it was stirred for an additional
10 min, the reaction mixture was filtered and the precipitate
was washed with methanol and dried in air to give 6 (0.73 g,
1
98%). Mp: 134-136 °C. H NMR ((CD3)2SO): δ 7.88 (d, 2H),
7.68 (d, 2H), 7.54 (t, 2H), 7.45 (t, 2H), 4.15 (s, 4H), 1.23 (s,
12H). 13C NMR (CDCl3): δ 28.0, 66.6, 67.0, 67.9, 79.1, 79.9,
82.9, 122.9, 126.9, 127.5, 127.8, 128.5, 131.8, 132.4, 137.2,
153.0, 165.7. 125Te NMR ((CD3)2SO): δ 533.4. MS: m/z 1189
(28%), 713 (39%), 630 (25%), 614 (12%), 585 (16%), 495 (56%),
478 (60%), 304 (79%). IR (KBr, cm-1): 1626, 1643 (νCdN). Anal.
Calcd for C22H24Cl2HgN2O2Te: C, 35.36; H, 3.23; N, 3.74.
Found: C, 35.92; H, 3.15; N, 3.69.
When complex 6 (0.5 g) was dissolved in CHCl3, an immedi-
ate color change to yellow was observed. Two fragments were
separated by column chromatography on silica gel using
petroleum ether/ethyl acetate (95:5).
Exp er im en ta l Section
All reactions were carried out under ambient conditions.
Organic solvents were purified by standard procedures and
were freshly distilled prior to use. Melting points were recorded
1
125
in capillary tubes and are uncorrected. H, 13C, 77Se, and
-
Te NMR spectra were obtained at 299.94, 75.42, 57.22, and
94.72 MHz, respectively, in CDCl3 on a Varian VXR 300S
spectrometer and a Bruker 500 spectrometer. Chemical shifts
are cited with respect to SiMe4 (1H, 13C) as an internal
standard and Me2Se (77Se) and Me2Te (125Te) as external
[C6H4(C5H8NO)TeCl] (7): yellow fraction; yield 0.18 g, 80%.
Mp: 175-177 °C. H NMR (CDCl3): δ 8.58 (d, 1H), 7.88 (dd,
1H), 7.56-7.62 (m, 1H), 7.39-7.45 (m, 1H), 4.57 (s, 2H), 1.58
(s, 6H). 13C NMR (CDCl3): δ 29.0, 66.7, 82.9, 122.9, 126.4,
128.3, 132.3, 133.3, 138.6, 167.9. 125Te NMR (CDCl3): δ 1202.8.
MS: m/z 339 (M+, 15%) 304 (100%), 561 (17%), 608 (38%). IR
(KBr, cm-1): 1611 (νCdN). Anal. Calcd for C11H12ClNOTe: C,
(16) (a) Cobbledick, R. E.; Einstein, F. W. B.; McWhinnie, W. R.;
Musa, F. H. J . Chem. Res., Synop. 1979, 145; J . Chem. Res., Miniprint
1979, 1901. (b) Majeed, Z.; McWhinnie, W. R.; Hamor, A. H. J .
Organomet. Chem. 1997, 549, 257.
(17) Hamor, T. A.; Chen, H.; McWhinnie, W. R.; McWhinnie, S. L.
W.; Majeed, Z. J . Organomet. Chem. 1996, 523, 53.
1
(18) (a) Gu¨l, N.; Nelson, J . H. J . Mol. Struct. 1999, 475, 121. (b)
Attar, S.; Nelson, J . H.; Fischer, J . Organometallics 1995, 14, 4776.

Bis[2-(4,4-dimethyl-w-oxazolinyl)phenyl] Chalcogenides
Organometallics, Vol. 22, No. 26, 2003 5477
Ta ble 1. Cr ysta l Da ta a n d Str u ctu r e Refin em en t
for 5, 7, a n d 8
X-r a y Cr ysta llogr a p h y. The X-ray diffraction measure-
ments were performed on a Siemens R3m/V diffractometer for
compounds 5, 7, and 8 and on a Bruker SMART diffractometer
with graphite-monochromated Mo KR radiation (λ ) 0.717 03
Å). The structures were solved by direct methods and subjected
to full-matrix least-squares refinement on F2 (program
SHELXL-97).19 The hydrogens were partially located from
difference electron-density maps, and the rest were fixed at
calculated positions. Scattering factors were taken from com-
mon sources. Some details of data collection and refinement
are given in Table 1.
5
7
8
empirical formula
C
22H24Cl2Hg-
N2O2Se
C
11H12Cl-
HgNO
C
11H12Cl-
NOTe
formula wt
cryst syst
space group
a (Å)
b (Å)
c (Å)
698.88
monoclinic
P21/c
12.589(2)
10.5362(19)
18.866(3)
106.010(12)
2405.3(7)
4
410.26
monoclinic
P21/m
337.27
monoclinic
P21/n
20.2339(16) 11.5638(15)
6.9091(8)
8.6311(9)
100.962(8)
1184.6(2)
4
2.300
13.191
760
9.1432(11)
12.7691(11)
113.481(9)
1238.3(2)
4
1.809
2.592
648
0.0272
â (deg)
V (Å3)
Z
Ack n ow led gm en t. We are grateful to the Depart-
ment of Science and Technology (DST), New Delhi,
India. Additional support from the Regional Sophisti-
cated Instrumentation Centre (RSIC), Indian Institute
of Technology (IIT), Bombay, India, for 300 MHz NMR
spectroscopy, Tata Institute of Fundamental Research
(TIFR), Mumbai, India, for 500 MHz NMR spectroscopy,
and Regional Sophisticated Instrumentation Centre
(RSIC), Central Drug Research Institute (CDRI), Luc-
know, India, for the FAB mass facility is gratefully
acknowledged. S.S.Z. thanks the CSIR for a fellowship.
R.J .B. wishes to acknowledge the DOD-ONR program
for funds to upgrade the diffractometer.
D(calcd) (Mg/m3)
1.930
8.155
abs coeff (mm-1
)
no. of obsd rflns (I > 2σ) 1336
final R(F) (I > 2σ(I))a
Rw(F2) (I > 2σ(I))
no. of data/restraints/
params
0.0373
0.0615
5452/0/300
0.0559
0.0745
2930/0/192
0.0334
2840/0/151
goodness of fit on F2
1.042
1.159
1.105
a
2
Definitions: R(Fo) ) ∑||Fo| - |Fc||/∑|Fo| and Rw(Fo2) ) {∑[w(Fo
- Fc2)2]/∑[w(Fc2)2}1/2
.
39.17; H, 3.58; N, 4.15. Found: C, 38.87; H, 3.47; N, 3.41.
HRMS (ES): m/z 304.0000 (calcd for [C11H12NOTe]+ (M - Cl)
303.9981).
[C6H4(C5H8NO)HgCl] (8): white fraction; yield 0.17 g, 60%.
Mp: 169-171 °C. 1H NMR (CDCl3): δ 7.86-7.89 (m, 1H),
7.49-7.52 (m, 1H), 7.33-7.44 (m, 2H), 4.23 (s, 2H), 1.39 (s,
6H). 13C NMR (CDCl3): δ 28.2, 67.3, 80.9, 128.2, 128.4, 132.2,
132.3, 136.9, 166.6. MS: m/z 412 (M+, 49%), 551 (34%), 529
Su p p or tin g In for m a tion Ava ila ble: Tables giving crys-
tallographic data for 5, 7 and 8; these data are also available
as CIF files. This material is available free of charge via the
Internet at http://pubs.acs.org.
(17%). IR (KBr, cm-1): 1644 (νCdN). Anal. Calcd for C11H12
-
OM034222S
ClHgNO: C, 32.22; H, 2.94; N, 3.41. Found: C, 32.97; H, 2.98;
N, 3.40. HRMS (ES): m/z 412.0395 (calcd for [C11H12NOHgCl]+
412.0392).
(19) Sheldrick, G. M. SHELX 97; Program for Crystal Structure
Refinement; University of Go¨ttingen, Go¨ttingen, Germany, 1997.