Metal complexes of alkyne-bridged α-amino acids

Article abstract of DOI:10.1002/(SICI)1099-0682(199811)1998:11<1791::AID-EJIC1791>3.0.CO;2-H

The palladium-mediated coupling of p-ethynylphenylalanine (p-epa) with different halogenated benzenes yielded alkyne-bridged α-amino acids. A series of cationic mono- to hexanuclear (Ph₃P)₂Pt complexes with the anions of p-ethynylphenylalanine and alkynyl- or benzene-bridged di-, tri-, tetra- and hexa-ethynyl phenylalanines as N,O-chelate ligands was prepared. N-t-Boc-p-ethynylphenylalanine methyl ester was metal-substituted to give complexes of the types Ph₃PAu-C≡C-R and (Et₃P)₂Pt-(C≡CR)₂. The benzene-bridged di-, tri-, tetra- and hexa-p-ethynylphenylalanine methyl esters form Schiff bases with ferrocene aldehyde and a tripodal ligand was obtained from. Ph₂PCH₂CH₂CH₂NH₂ and the benzene-bridged triethynylphenyl-alanine. The structure of (Ph₃P)₂Pt[NH₂C(H)-(CH₂C ₆H₄C≡CH)CO₂]⁺ BF₄^- was determined by X-ray diffraction.

Full text of DOI:10.1002/(SICI)1099-0682(199811)1998:11<1791::AID-EJIC1791>3.0.CO;2-H

FULL PAPER
[᭛]
Metal Complexes of Biologically Important Ligands, CVIII
Metal Complexes of Alkyne-Bridged ␣-Amino AcidsȠ
Bernd Kayser, Janina Altman, Heinrich Nöth[2], Jörg Knizek[2], and Wolfgang Beck*
Institut für Anorganische Chemie der Ludwig-Maximilians-Universität,
Meiserstraße 1, D-80333 München, Germany
Received June 8, 1998
Keywords: p-Ethynylphenylalanine / Alkyne-bridged α-amino acids / N,O-Chelate complexes / Ferrocenes / Schiff bases /
Platinum / Gold
The palladium-mediated coupling of p-ethynylphen-
ylalanine (p-epa) with different halogenated benzenes
yielded alkyne-bridged α-amino acids. A series of cationic
mono- to hexanuclear (Ph3P)2Pt complexes with the anions
of p-ethynylphenylalanine and alkynyl- or benzene-bridged
di-, tri-, tetra- and hexa-ethynyl phenylalanines as N,O-
chelate ligands was prepared. N-t-Boc-p-ethynylphenyl-
alanine methyl ester was metal-substituted to give
complexes of the types Ph3PAu-CϵC–R and (Et3P)2Pt-
(CϵCR)2. The benzene-bridged di-, tri-, tetra- and hexa-p-
ethynylphenylalanine methyl esters form Schiff bases with
ferrocene aldehyde and a tripodal ligand was obtained from
Ph2PCH2CH2CH2NH2 and the benzene-bridged tri-
ethynylphenyl-alanine. The structure of (Ph3P)2Pt[NH2C(H)-
–
(CH2C6H4CϵCH)CO2]+ BF4 was determined by X-ray
diffraction.
Results and Discussion
Non-proteinogenic amino acids influence the biological
properties of peptides and are useful for the synthesis of
peptidomimetics[3]. The synthesis of unnatural amino acids
is based either on electrophilic[4] or nucleophilic[5] equiva-
lents. A valuable building block for the derivatization of
Chloro-bridged metal complexes have proven to be ideal
starting materials for the synthesis of N,O-α-aminocarbox-
ylate metal compounds[16]. We have chosen the chloro-
bridged complexes [(Ph3P)2Pt(µ-Cl)2Pt(PPh3)2]2ϩ, (Et3P)-
(Cl)Pd(µ-Cl)Pd(Cl)(PEt3) and Cp*(Cl)Rh(µ-Cl)2Rh(Cl)Cp*
from which N,O-chelates with natural α-amino acids have
been obtained in our group.[16][17][18][19]
phenylalanines has been developed by Schwabacher et al.[6]
.
p-Iodophenylalanine was used as starting material to build,
under palladium catalysis, amino acids which are bridged
by a heteroatom[6] or the iodo substituent was replaced by
sulfur-containing fragments or trimethyltin[7]. The pal-
The reaction of the chloro-bridged cationic complex
ladium-mediated coupling of terminal acetylides with p- {[(Ph3P)2Pt(µ-Cl)]2}{BF4}2 with the anion of p-ethynyl-
iodophenylalanine afforded fluorescent marker mol- phenylalanine yielded the cationic N,O-chelate 1.
ecules[8a], which find growing attention in organometallic
chemistry[8b-e]. Undheim et al. and Savi et al. reported the
Pd-catalyzed synthesis of a series of α,αЈ-hydrocarbon
bis(α-amino acids), including α,αЈ-alkynyl-bridged bis(gly-
cines) and of alkyneϪbridged oxazolidines[9]
.
By means of the Heck[10], especially the Sonogashira re-
action[11], we were able to synthesize various acetylide-
bridged phenylalanines[12a]. p-Ethynylphenylalanine was
proven to be a potent inhibitor of the enzyme tryptophan-
hydroxylase[13]; therefore structural details of this com-
pound appear of interest. The bis-, tris-, tetra- and hexa-
podal[12b] amino acids should be useful starting compounds
in peptide chemistry, for the synthesis of organic as well as
metallo-dendrimers[14], and for linearly-bridged metal com-
plexes with unusual optical or electrical properties[15]. The
scope of organometallic complexes of α-amino acids and
Suitable crystals for structure determination by X-ray dif-
fraction of 1 were obtained by liquid-liquid diffusion of di-
ethyl ether into an methanolic solution of 1 at room tem-
perature. By this means the structure of the new non-pro-
teinogenic amino acid p-ethynylphenylalanine (p-epa)[12a]
has been established. The PtϪligand atom distances are
close to those of similar complexes, e.g. (nBu3P)(Cl)-
Pt(O2CCH2NϭC(H)NMe2)[20a]
, (dppe)Pt[N(COMe)CH2-
peptides has been recently reviewed[16]
.
CO2][20b] and (Ph3P(Cl)Pt(NH2CMe2CO2)[20c]
.
In this paper we wish to present the coordination chemis-
try of the new amino acid derivatives.
The bond angle C11ϪC10ϪC7 is not exactly linear.
The analogous reactions of bis-, tris-, tetra- and hexa-
ethynylphenylalanine derivatives gave the cationic com-
plexes 2Ϫ7.
For part CVII see ref.[1]
.
[᭛]
Eur. J. Inorg. Chem. 1998, 1791Ϫ1798
WILEY-VCH Verlag GmbH, D-69451 Weinheim, 1998
1434Ϫ1948/98/1111Ϫ1791 $ 17.50ϩ.50/0
1791

B. Kayser, J. Altman, H. Nöth, J. Knizek, W. Beck
Figure 1. Structure of complex 1[a]
FULL PAPER
[a] Selected bond lengths [pm] and angles [°]: PtϪP1 225.3 (2), PtϪP2 225.8 (2), PtϪN1 209.5 (8), PtϪO1 207.1 (7), C10ϪC11 117.2 (17);
N1ϪPtϪP2 165.9 (2), N1ϪPtϪP1 95.0 (2), O1ϪPtϪN1 81.0 (3), O1ϪPtϪP2 85.18 (19), C7ϪC10ϪC11 173.1 (16).
The IR spectra of the compounds 2Ϫ7 exhibit character- blets due to the different ligands trans to the P atoms with
istic absorptions for η2-coordinated α-amino carboxylates corresponding platinum satellites (195Pt- 31P coupling).
at ν ഠ 1675 cmϪ1 next to the ν(CϵC) vibrations at ν ഠ
Terminal acetylide functions in organic molecules have
2205 cmϪ1. The high symmetry of 2Ϫ7 is manifested in successfully been used to build metal acetylide complexes
1
the H- and 13C-NMR spectra. Only one set of signals is which are also of interest for nonlinear optics. On the other
observed. The 31P-NMR spectra show a set of double dou- hand the metal atom of bis(acetylide) complexes can func-
1792
Eur. J. Inorg. Chem. 1998, 1791Ϫ1798

Metal Complexes of Biologically Important Ligands, CVIII
FULL PAPER
tion as a linker and support the conjugation of biological ν(CϵC) absorption is found at 2103 cmϪ1. The other spec-
molecules[21]. Following known procedures[22] p-epa was troscopic data could be compared to similar known com-
treated with Ph3PAuCl and trans-(Ph3P)2PtCl2 to yield the pounds[22]
.
compounds 8 and 9.
Ferrocenyl Schiff base complexes of amino acids find ap-
1
Complexes 8 and 9 were characterized by IR-, H-, 13C- plication as lipophilic and chromophoric groups for mask-
and 31P-NMR spectroscopy. For 9 the characteristic ing of peptide bonds[23a]. Also interactions of the redoxac-
Eur. J. Inorg. Chem. 1998, 1791Ϫ1798
1793

B. Kayser, J. Altman, H. Nöth, J. Knizek, W. Beck
FULL PAPER
tive ferrocenyl unit and redoxactive enzymes are objects of Experimental Section
investigations[23b]
.
The
condensation
between
General: All reactions were carried out in dry solvents under argon.
Ϫ NMR: Jeol GSX 270 (1H 270.0; 13C 67.9; 31P 109.3 MHz). Tetra-
methylsilane as internal standard; H3PO4 (85%) as external stand-
ferrocenecarbaldehyde and the corresponding phenylala-
nine esters afforded the orange Schiff base complexes
10Ϫ13. For recent examples of star-shaped metal complexes ard. Ϫ IR: 5ZDX FT-IR. Ϫ ClAu(PPh3)[26], trans-Pt(PEt3)2Cl2
[27a], {[(Ph3P)2Pt(µ-Cl)]2}{BF4}2 [28], [(Et3P)PdCl(µ-Cl)]2 [27b], [Cp*
derived from 1,3,5-triethynylbenzene as in 5 and 11 see
RhCl(µ-Cl)]2 [29], 3-diphenylphosphanyl-n-propylamine[30] and the
acetylide-substituted phenylalanines were prepared according to
literature procedures[12]. Formylferrocene was purchased from
Fluka and stored in the dark under argon.
ref.[24]
.
The successful formation of the Schiff base is proven by
the intense ν(CϭN) IR absorption band at 1636 cmϪ1 and
1
by the imine proton signal ( δ ഠ 7.90 ) in the H-NMR
1
{( Ph3P) 2Pt[ ( NH2) ( O2C) CHCH2C6H4CϵCH] }BF4 (1): To a
solution of 34 mg (0.15 mmol) of p-ethynylphenylalanine hydro-
chloride in 10 ml of methanol was added 0.30 mmol of NaOMe
and the mixture was stirred for 5 min. at room temperature. After
addition of a solution of 120 mg (0.075mmol) of {[(Ph3P)2Pt(µ-
Cl)]2}{BF4}2 in 10 ml of dichloromethane, the mixture was stirred
for additional 3 h. The volatiles were evaporated, the residue was
washed two times with 5 ml of water and dried at 50°C in vacuo.
The resulting powder was finally recrystallized several times from
dichloromethane/diethyl ether. Yield 121 mg (81%), colorless pow-
der, m.p. 250°C (decomp.). Ϫ IR (KBr): ν˜ ϭ 3295 cmϪ1 m (NH2),
1654 s (CO2), 1084 s (BF4). Ϫ 1H NMR (CDCl3): δ ϭ 2.85 (dd,
spectrum. The H-NMR signal of the H atom at α-C was
not observed.
A
correlated 1H/1H-NMR experiment
showed that the α-proton has the same chemical shift as the
OCH3 group of the methyl ester.
Using common methods of peptide chemistry the tri-
podal tris amino acid was derivatized and treated with 3-
diphenylphosphanyl-n-propylamine to give the tripodal
phosphane ligand 14 which may function as a tridentate
chelate ligand. The reaction of 14 with 0.5 equivalents of
[Rh(COD)Cl]2 (COD ϭ 1,5-cyclooctadiene) gave no de-
fined compound, probably because the phosphane groups
are not pre-organized. On the other hand the reactions of
14 with 1,5 equivalents of [(Et3P)PdCl(µ-Cl)]2 or [Cp*
RhCl(µ-Cl)]2 (Cp* ϭ pentamethylcyclopentadienyl) yielded
the three core complexes 15 and 16.
2
2J ϭ 14.6 Hz, 3J ϭ 3.4 Hz, 1 H, CHЈH), 3.13 (dd, J ϭ 14.6 Hz,
3J ϭ 7.5 Hz, 1 H, CHHЈ), 3.16 (s, 1 H, CH), 3.19Ϫ3.30 (m, 1 H,
3
CH), 3.98Ϫ4.12 (m, 2 H, NH2), 6.95 (d, J ϭ 8.1 Hz, 2 H, C6H4),
7.15Ϫ7.50 (m, 32 H, C6H4, PPh3). Ϫ 13C NMR (CDCl3): δ ϭ 38.90
(CH2), 56.58 (CH), 77.76 (CϵCH), 83.41 (CϵCH), 120.85, 125.33
1
1
(d, J ϭ 84.1 Hz, i-PPh3), 126.38 (d, J ϭ 83.5 Hz, i-PPh3), 128.61
(d, 3J ϭ 11.4 Hz, m-PPh3), 129.17 (d, 3J ϭ 11.5 Hz, m-PPh3),
129.60, 131.66 (d, J ϭ 2.3 Hz, p-PPh3), 132.21 (d, J ϭ 2.2 Hz, p-
PPh3), 132.66, 133.91 (d, 2J ϭ 10.8 Hz, o-PPh3), 134.59 (d, 2J ϭ
10.6 Hz, o-PPh3), 136.91, 182.94 (CO2). Ϫ 31P NMR (CDCl3): δ ϭ
7.70 (d, J ϭ 24.3 Hz, J ϭ 3586 Hz), 8.54 (d, J ϭ 24.3 Hz, J ϭ
3484 Hz). Ϫ C47H40BF4NO2P2Pt (994.7): calcd. C 56.75, H 4.05,
N 1.41; found C 56.80, H 4.05, N 1.15.
4
4
2
1
2
1
{( Ph3P)2Pt[( NH2) (CO2)CHCH2C6H4CϵCC6H4CH2CH(CO2)-
( NH2) ] Pt( PPh3) 2}{BF4}2 (2): The reaction was carried out as de-
scribed for 1 with 43 mg (0.10 mmol) of the ligand of 2 as dihydro-
chloride, 0.40 mmol of NaOMe, 160 mg (0.10 mmol) of
{[(Ph3P)2Pt(µ-Cl)]2}{BF4}2 for 16 h. Yield 178 mg (91%), colorless
Ϫ1
˜
powder, m.p. 220°C (decomp.). Ϫ IR (KBr): ν ϭ 3303 cm
m
(NH2), 1676 s (CO2), 1084 s (BF4). Ϫ 1H NMR (CDCl3ϩCD3OD):
δ ϭ 2.99 (dd, 2J ϭ 14.9 Hz, 3J ϭ 4.9 Hz, 2 H, CHЈH), 3.11 (dd,
2J ϭ 14.9 Hz, J ϭ 7.6 Hz, 2 H, CHHЈ), 3.97Ϫ4.08 (m, 2 H, CH),
3
6.99 (d, 3J ϭ 8.3 Hz, 4 H, C6H4), 7.10Ϫ7.47 (m, 64 H, C6H4, PPh3).
Ϫ
13C NMR (CDCl3ϩCD3OD): δ ϭ 38.69 (CH2), 56.48 (CH),
1
89.33 (CϵC), 121.75, 124.94 (d, J ϭ 77.0 Hz, i-PPh3), 125.85 (d,
1J ϭ 74.9 Hz, i-PPh3), 128.40 (d, 3J ϭ 11.4 Hz, m-PPh3), 128.97
3
(d, J ϭ 11.3 Hz, m-PPh3), 129.26, 131.64, 132.01 (p-PPh3), 132.17
(p-PPh3), 133.53 (d, 2J ϭ 10.3 Hz, o-PPh3), 134.21 (d, 2J ϭ 10.5
Hz, o-PPh3), 135.94, 183.71 (CO2).
Ϫ
31P NMR
The 31P-NMR spectrum of 15 shows several signal sets
due to cis and trans isomers with the most intensive one
having a coupling constant of 538 Hz. This coupling con-
stant is typical for trans-situated phosphanes[25]. In con-
trast, compound 16 is formed as one isomer with a doublet
2
1
(CDCl3ϩCD3OD): δ ϭ 7.54 (d, J ϭ 24.1 Hz, J ϭ 3610 Hz), 8.29
(d, 2J ϭ 24.1 Hz, 1J ϭ 3466 Hz). Ϫ C92H78B2F8N2O4P4Pt2
(1963.3): calcd. C 56.28, H 4.01, N 1.43; found C 55.72, H 4.08,
N 1.34.
{( Ph3P) 2Pt[ ( NH2) ( CO2) CHCH2C6H4CϵCCϵCC6H4CH2CH-
( CO2) ( NH2) ] Pt( PPh3) 2}{BF4}2 (3): The reaction was carried out
as described for 1 with 45 mg (0.10 mmol) of the ligand of 3 as
dihydrochloride, 0.40 mmol of NaOMe, 160 mg (0.10 mmol) of
{[(Ph3P)2Pt(µ-Cl)]2}{BF4}2 for 16 h. Yield 184 mg (93%), colorless
1
in the 31P-NMR spectrum due to the JRh-P coupling of
143 Hz.
Generous support by Deutsche Forschungsgemeinschaft, Fonds
der Chemischen Industrie and Wacker Chemie, München, is grate-
fully acknowledged. We thank Degussa AG, Hanau, for gifts of powder, m.p. 235°C (decomp.). Ϫ IR (KBr): ν˜ ϭ 3303, 3223 cmϪ1
chemicals.
1794
m
(NH2), 1679
s
(CO2), 1084
s
(BF4).
Ϫ
1H NMR
Eur. J. Inorg. Chem. 1998, 1791Ϫ1798

Metal Complexes of Biologically Important Ligands, CVIII
FULL PAPER
(CDCl3ϩCD3OD): δ ϭ 2.90Ϫ3.04 (m, 4 H, CH2), 3.95Ϫ4.03 (m,
39.04 (CH2), 56.68 (CH), 87.74, 95.49 (CϵC), 121.05, 125.05 (d,
1J ϭ 89.7 Hz, i-PPh3), 125.25, 126.03 (d, 1J ϭ 88.9 Hz, i-PPh3),
128.38 (d, 3J ϭ 11.6 Hz, m-PPh3), 128.89 (d, 3J ϭ 10.9 Hz, m-
PPh3), 129.23, 131.57 (p-PPh3), 131.95, 132.04 (p-PPh3), 133.56 (d,
2J ϭ 10.6 Hz, o-PPh3), 134.02, 134.33 (d, 2J ϭ 10.5 Hz, o-PPh3),
136.89, 183.46 (CO2). Ϫ 31P NMR (CDCl3ϩCD3OD): δ ϭ 7.40 (d,
2J ϭ 23.9 Hz, 1J ϭ 3622 Hz), 8.47 (d, 2J ϭ 23.9 Hz, 1J ϭ 3440 Hz).
Ϫ C194H158B4F16N4O8P8Pt4 ϫ CH2Cl2 (4133.7): calcd. C 56.65, H
3.90, N 1.35; found C 56.10, H 3.99, N 1.15.
3
2 H, CH), 6.97 (d, J ϭ 7.8 Hz, 4 H, C6H4), 7.16Ϫ7.46 (m, 64 H,
C6H4, PPh3). Ϫ 13C NMR (CDCl3ϩCD3OD): δ ϭ 38.86 (CH2),
1
56.66 (CH), 74.22, 81.34 (CϵC), 120.28, 125.05 (d, J ϭ 79.8 Hz,
1
3
i-PPh3), 126.03 (d, J ϭ 78.1 Hz, i-PPh3), 128.53 (d, J ϭ 11.4 Hz,
m-PPh3), 129.09 (d, 3J ϭ 11.2 Hz, m-PPh3), 129.44, 131.74 (p-
PPh3), 132.25 (p-PPh3), 132.96, 133.65 (d, 2J ϭ 11.1 Hz, o-PPh3),
2
3
134.38 (d, J ϭ 10.3 Hz, o-PPh3), 137.34, 183.43 (d, J ϭ 5.2 Hz,
CO2). Ϫ 31P NMR (CDCl3ϩCD3OD): δ ϭ 7.43 (d, J ϭ 24.4 Hz,
2
1J ϭ 3506 Hz), 8.47 (d, 2J ϭ 24.4 Hz, 1J ϭ 3445 Hz). Ϫ
C94H78B2F8N2O4P4Pt2 ϫ CH2Cl2 (2072.3): calcd. C 55.06, H 3.89,
N 1.35; found C 54.60, H 3.92, N 1.30.
{1,2,3,4,5,6-C6[ CϵCC6H4CH2CH( CO2) ( NH2) Pt( PPh3) 2] 6}-
{BF4}6 (7): The reaction was carried out as described for 1 with 71
mg (0.05 mmol) of the ligand of 7 as hexahydrochloride, 0.60 mmol
of NaOMe, 240 mg (0.15 mmol) of {[(Ph3P)2Pt(µ-Cl)]2}{BF4}2 for
16 h. Yield 244 mg (81%), brown powder, m.p. 300°C (decomp.).
Ϫ IR (KBr): ν˜ ϭ 3304, 3231 cmϪ1 m (NH2), 2198 (CϵC), 1675 s
{1,4-C6H 4[ CϵCC6H 4CH 2CH ( CO2) ( NH2) P t( P P h3) 2] 2}-
{BF4}2 (4): The reaction was carried out as described for 1 with 53
mg (0.10 mmol) of the ligand of 4 as dihydrochloride, 0.40 mmol
of NaOMe, 160 mg (0.10 mmol) of {[(Ph3P)2Pt(µ-Cl)]2}{BF4}2 for
16 h. Yield 184 mg (89%), colorless powder, m.p. 260°C (decomp.).
Ϫ IR (KBr): ν˜ ϭ 3299, 3223 cmϪ1 m (NH2), 2213 (CϵC), 1666 s
1
(CO2), 1084 s (BF4). Ϫ H NMR (CDCl3ϩCD3OD): δ ϭ 2.82 (pt,
J ϭ 11.9 Hz, 6 H, CHЈH), 3.19 (pt, J ϭ 10.7 Hz, 6 H, CHHЈ), 4.29
3
2
(CO2), 1084 s (BF4). Ϫ 1H NMR (CDCl3): δ ϭ 2.89 (dd, J ϭ 13.6
(pt, J ϭ 14.7 Hz, 6 H, CH), 7.09Ϫ7.51 (m, 204 H, C6H4, PPh3).
Ϫ
13C NMR (CDCl3ϩCD3OD): δ ϭ 39.18 (CH2), 56.47 (CH),
Hz, 3J ϭ 4.3 Hz, 2 H, CHЈH), 3.13 (dd, 2J ϭ 13.6 Hz, 3J ϭ 7.2
Hz, 2 H, CHHЈ), 3.32Ϫ3.47 (m, 2 H, CH), 3.98Ϫ4.19 (m, 4 H,
NH2), 7.01 (d, 3J ϭ 8.3 Hz, 4 H, C6H4), 7.12Ϫ7.49 (m, 64 H, C6H4,
PPh3), 7.59 (s, 4 H, C6H4). Ϫ 13C NMR (CDCl3): δ ϭ 38.70 (CH2),
56.50 (CH), 89.50, 90.75 (CϵC), 121.81, 122.88, 125.01 (d, 1J ϭ
87.23, 99.70 (CϵC), 120.92, 125.32 (d, 1J ϭ 110.8 Hz, i-PPh3),
1
3
126.29 (d, J ϭ 108.1 Hz, i-PPh3), 127.82, 128.56 (d, J ϭ 10.7 Hz,
m-PPh3), 129.02 (d, 3J ϭ 12.8 Hz, m-PPh3), 129.72, 131.59 (p-
PPh3), 132.12 (p-PPh3), 132.18, 133.74 (d, 2J ϭ 10.0 Hz, o-PPh3),
134.61 (d, 2J ϭ 8.9 Hz, o-PPh3), 137.63, 183.14 (CO2). Ϫ 31P NMR
(CDCl3ϩCD3OD): δ ϭ 7.32 (d, J ϭ 23.6 Hz, J ϭ 3623 Hz), 8.79
(d, J ϭ 23.6 Hz, J ϭ 3477 Hz). Ϫ C288H234B6F24N6O12P12Pt6
1
3
78.9 Hz, i-PPh3), 125.90 (d, J ϭ 76.4 Hz, i-PPh3), 128.49 (d, J ϭ
11.2 Hz, m-PPh3), 129.05 (d, 3J ϭ 11.1 Hz, m-PPh3), 129.28,
131.44, 131.71, 132.08 (p-PPh3), 132.26 (p-PPh3), 133.57 (d, 2J ϭ
2
1
2
1
ϫ
2
2 CH2Cl2 (6203.9): calcd. C 56.14, H 3.86, N 1.35; found C 55.53,
H 4.09, N 1.18.
10.6 Hz, o-PPh3), 134.27 (d, J ϭ 10.8 Hz, o-PPh3), 135.97, 183.75
(d, 3J ϭ 4.0 Hz, CO2). Ϫ 31P NMR (CDCl3): δ ϭ 7.71 (d, 2J ϭ
1
2
1
24.2 Hz, J ϭ 3595 Hz), 8.55 (d, J ϭ 24.2 Hz, J ϭ 3446 Hz). Ϫ
C100H82B2F8N2O4P4Pt2 ϫ 1/2 CH2Cl2 (2105.9): calcd. C 57.48, H
3.98, N 1.33; found C 57.29, H 4.23, N 1.25.
General Procedure for the Preparation of the σ-Acetylide Metal
Complexes 8 and 9: To a solution of 99 mg (0.20 mmol) of
ClAu(PPh3) or 100 mg (0.20 mmol) of trans-Pt(PEt3)2Cl2 in 10 ml
of diethylamine were added 67 mg (0.22 mmol) or 133 mg (0.44
mmol) of N-t-Boc-4-ethynyl--phenylalanine methyl ester and a
catalytic amount of CuI. The solutions were stirred at room temp.
for 3 h in the dark and the volatiles were evaporated. The residues
were each extracted with a mixture of dichloromethane/diethyl
ether (1/3; 5 ml) and the solvent was evaporated. The resulting pre-
cipitates were washed with pentane (2 ϫ 10 ml) and dried in vacuo.
{1,3,5-C6H3[ CϵCC6H4CH2CH( CO2) ( NH2) Pt( PPh3) 2] 3}-
{BF4}3 (5): The reaction was carried out as described for 1 with 75
mg (0.10 mmol) of the ligand of 5 as trihydrochloride, 0.60 mmol
of NaOMe, 240 mg (0.15 mmol) of {[(Ph3P)2Pt(µ-Cl)]2}{BF4}2 for
16 h. Yield 256 mg (84%), colorless powder, m.p. 270°C (decomp.).
Ϫ IR (KBr): ν˜ ϭ 3300, 3225 cmϪ1 m (NH2), 2208 (CϵC), 1674 s
(CO2), 1085 s (BF4).
Ϫ
1H NMR (CDCl3ϩCD3OD): δ ϭ
2.89Ϫ3.15 (m, 6 H, CH2), 4.03 (pt, 3J ϭ 6.4 Hz, 3 H, CH), 6.98
(d, 3J ϭ 8.0 Hz, 6 H, C6H4), 7.10Ϫ7.46 (m, 96 H, C6H4, PPh3),
7.69 (s, 3 H, C6H3). Ϫ 13C NMR (CDCl3ϩCD3OD): δ ϭ 38.73
(CH2), 56.58 (CH), 87.95, 90.17 (CϵC), 121.27, 123.87, 124.99 (d,
( PPh3) Au{CϵCC6H4CH2CH[ NHCO2C( CH3) 3] ( CO2Me) }
(8): Yield 131 mg (86%), colorless powder, m.p. 99°C (decomp.).
Ϫ IR (KBr): ν˜ ϭ 3439 cmϪ1 (NH), 1743 m, 1713 s (CO2, CON).
1
Ϫ H NMR (CDCl3): δ ϭ 1.39 (s, 9 H, CH3), 2.93Ϫ3.09 (m, 2 H,
1
1J ϭ 79.0 Hz, i-PPh3), 125.95 (d, J ϭ 77.4 Hz, i-PPh3), 128.45 (d,
CH2), 3.65 (s, 3 H, CH3), 4.53 (pq, 3J ϭ 6.1 Hz, 1 H, CH), 4.92
(d, 3J ϭ 8.4 Hz, 1 H, NH), 6.99 (d, 3J ϭ 8.1 Hz, 2 H, C6H4),
7.39Ϫ7.56 (m, 17 H, PPh3, C6H4). Ϫ 13C NMR (CDCl3): δ ϭ 28.36
[C(CH3)3], 38.32 (CH2), 52.55 (CH3), 54.39 (CH), 79.94 [C(CH3)3],
83.35, 105.09 (CϵC), 123.62, 128.99, 129.21 (d, 3J ϭ 11.4 Hz, m-
PPh3), 131.67, 131.80 (d, 1J ϭ 8.9 Hz, i-PPh3), 132.57, 134.35 (d,
2J ϭ 13.7 Hz, o-PPh3), 134.70 (24 C, C6H4, PPh3), 155.14 (CON),
172.40 (CO2). Ϫ 31P NMR (CDCl3): δ ϭ 42.84. Ϫ C35H35NO4PAu
ϫ 1/2 CH2Cl2 (804.1): calcd. C 53.02, H 4.51, N 1.74; found C
52.54, H 4.13, N 1.46.
3
3J ϭ 11.3 Hz, m-PPh3), 129.02 (d, J ϭ 11.4 Hz, m-PPh3), 131.67
(p-PPh3), 132.11 (p-PPh3), 132.18, 133.89 (d, 2J ϭ 10.6 Hz, o-PPh3),
2
133.89, 134.25 (d, J ϭ 10.6 Hz, o-PPh3), 136.41, 183.56 (CO2). Ϫ
31P NMR (CDCl3ϩCD3OD): δ ϭ 7.56 (d, 2J ϭ 24.0 Hz, 1J ϭ 3623
Hz), 8.53 (d, 2J
ϭ
24.0 Hz, 1J
ϭ
3440 Hz).
Ϫ
C147H120B3F12N3O6P6Pt3 ϫ CH2Cl2 (3141.1): calcd. C 56.59, H
3.91, N 1.34; found C 56.49, H 4.00, N 1.17.
{1,2,4,5-C6H2[ CϵCC6H4CH2CH( CO2) ( NH2) Pt( PPh3) 2] 4}-
{BF4}4 (6): The reaction was carried out as described for 1 with 73
mg (0.075 mmol) of the ligand of 6 as tetrahydrochloride, 0.60
trans-( P Et3) 2P t{CϵCC6H 4CH 2CH [ NH CO2C( CH 3) 3] -
mmol of NaOMe, 240 mg (0.15 mmol) of {[(Ph3P)2Pt(µ- ( CO2Me) }2 (9): Yield 182 mg (88%), yellow powder, m.p. 135°C
Cl)]2}{BF4}2 for 16 h. Yield 261 mg (86%), brown powder, m.p.
(decomp.). Ϫ IR (KBr): ν˜ ϭ 3443 cmϪ1 (NH), 2102 s (CϵC), 1745
1 3
276°C (decomp.). Ϫ IR (KBr): ν˜ ϭ 3299, 3225 cmϪ1 m (NH2),
m, 1715 s (CO2, CON). Ϫ H NMR (CDCl3): δ ϭ 1.46 (dt, J ϭ
2198 (CϵC), 1674
s
(CO2), 1084
s
(BF4).
Ϫ
1H NMR
8.3 Hz, 3J ϭ 7.8 Hz, 18 H, CH3), 1.35 (s, 18 H, CH3), 2.10 (tq,
(CDCl3ϩCD3OD): δ ϭ 2.82 (dd, 2J ϭ 14.1 Hz, 3J ϭ 11.2 Hz, 4 2J ϭ 7.4 Hz, J ϭ 7.8 Hz, 12 H, CH2), 2.88Ϫ3.02 (m, 4 H, CH2),
3
3
3
H, CHЈH), 3.08Ϫ3.20 (m, 4 H, CHHЈ), 4.03Ϫ4.17 (m, 4 H, CH),
6.99 (d, 3J ϭ 7.7 Hz, 8 H, C6H4), 7.09Ϫ7.45 (m, 128 H, C6H4,
PPh3), 7.76 (s, 2 H, C6H2). Ϫ 13C NMR (CDCl3ϩCD3OD): δ ϭ 8.0 Hz, 4 H, C6H4). Ϫ 13C NMR (CDCl3): δ ϭ 8.22 (t, J ϭ 12.2
3.65 (s, 6 H, CH3), 4.48 (pq, J ϭ 7.2 Hz, 2 H, CH), 4.87 (d, J ϭ
3
3
8.3 Hz, 2 H, NH), 6.89 (d, J ϭ 8.0 Hz, 4 H, C6H4), 7.13 (d, J ϭ
2
Eur. J. Inorg. Chem. 1998, 1791Ϫ1798
1795

B. Kayser, J. Altman, H. Nöth, J. Knizek, W. Beck
FULL PAPER
Hz, CH3), 16.16 (t, 1J ϭ 17.9 Hz, CH2), 28.18 [C(CH3)3], 37.95
(CH2), 52.15 (CH3), 54.23 (CΗ), 79.87 [C(CH3)3], 109.00, 128.99,
131.09, 132.62 (12 C, C6H4), 155.23 (CON), 172.55 (CO2). Ϫ 31P
NMR (CDCl3): δ ϭ 11.50 (1J ϭ 2371 Hz). Ϫ C46H70N2O8P2Pt
(1036.1): calcd. C 53.33, H 6.81, N 2.70; found C 52.71, H 6.67,
N 2.69.
1,2,3,4,5,6-C6[ -CϵC-C6H4-CH2-C H ( C O2C H 3) ( NϭC -Fc) ]
(13): The reaction was carried out as described for 10 with 75 mg
(0.05 mmol) of the ligand of 7 as hexahydrochloride hexamethyl
ester, 45.7 µl (0.33 mmol) of triethylamine and 70 mg (0.33 mmol)
of ferrocenealdehyde. Yield 96 mg (78%), orange powder, m.p.
131°C (decomp.). Ϫ IR (KBr): ν˜ ϭ 2206 cmϪ1 w (CϵC), 1739 s
(CO2), 1636 s (CϭN). Ϫ 1H NMR (CDCl3): δ ϭ 3.15 (dd, 2J ϭ
1,4-C6H4[ -CϵCC6H4CH2CH( CO2CH3) ( NϭC-Fc) ] (10): To a
solution of 112 mg (0.20 mmol) of the ligand of 4 as dihydrochlo-
ride dimethyl ester in 20 ml of dichloromethane were added 61.8
µl (0.44 mmol) of triethylamine. The solution was stirred at room
temperature for 15 min, 96 mg (0.44 mmol) of ferrocenealdehyde
and 150 mg of MgSO4 were added and stirring was continued for
24 h in the dark. The precipitate was separated by centrifugation,
the volatiles were evaporated from the supernatant solution, and
the residue was extracted with a mixture of diethyl ether/tetra-
hydrofuran (3/1; 2 ϫ 15 ml). The solvent was evaporated, the re-
sulting precipitate was washed with pentane (3 ϫ 10 ml) and dried
in vacuo. Yield 138 mg (79%), orange powder, m.p. 108°C (de-
3
2
3
13.6 Hz, J ϭ 9.2 Hz, 6 H, CHЈH), 3.36 (dd, J ϭ 13.6 Hz, J ϭ
5.2 Hz, 6 H, CHHЈ), 3.75 (s, 18 H, CH3), 4.06 (s, 36 H, CH, C5H5),
4.37 (s, 12 H, C5H5), 4.58 (s, 6 H, C5H5), 4.68 (s, 6 H, C5H5), 7.16
3
3
(d, J ϭ 8.2 Hz, 12 H, C6H4), 7.44 (d, J ϭ 8.2 Hz, 12 H, C6H4),
7.95 (s, 6 H, CH). Ϫ 13C NMR (CDCl3): δ ϭ 39.34 (CH2), 52.33
(CH3), 68.75, 68.96, 69.15, 70.84 (C5H5), 74.65 (CH), 79.30 (C5H5),
87.23, 99.13 (CϵC), 121.25, 127.22, 129.74, 131.73, 139.05 (42 C,
C6H4, C6), 164.73 (CϭN), 171.78 (CO2). Ϫ C144H120N6O12Fe6
ϫ
2 CH2Cl2 (2631.3): calcd. C 66.63, H 4.75, N 3.19; found C 66.23,
H 4.89, N 3.14.
1,3,5-C6H 3{CϵCC6H 4CH 2CH [ NH CO2C( CH 3) 3] [ CO2-
( CH2) 3PPh2] }3 (14): To a solution of 94 mg (0.10 mmol) of the
ligand of 5 as N-Boc-protected triacid in 5 ml of tetrahydrofuran
was added a solution of 98 mg (0.40 mmol) of 3-diphenylphos-
phanyl-n-propylamine in 5 ml of tetrahydrofuran and 38.0 µl (0.30
mmol) of N-ethylmorpholine. The solution was cooled to 0°C and
81 mg (0.60 mmol) of 1-hydroxybenzotriazole and 96 mg (0.50
mmol) of 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide hydro-
chloride were added. After stirring for 24 h, evaporation of the
solvent gave a colorless residue from which the product was isolated
by flash chromatography (silica gel, 30 cm, CH2Cl2/methanol 30:1).
Yield 123 mg (76%), colorless powder, m.p. 185°C. Ϫ IR (KBr):
ν˜ ϭ 3322 cmϪ1 m (NH), 2211 w (CϵC), 1706 s, 1684 s, 1651 s
(CO2, CON). Ϫ 1H NMR (CDCl3): δ ϭ 1.37 (s, 27 H, CH3),
comp.). Ϫ IR (KBr): ν ϭ 2216 cmϪ1 w (CϵC), 1737 s (CO2), 1635
˜
1
2
3
s (CϭN). Ϫ H NMR (CDCl3): δ ϭ 3.16 (dd, J ϭ 14.1 Hz, J ϭ
8.8 Hz, 2 H, CHЈH), 3.34 (dd, 2J ϭ 14.1 Hz, 3J ϭ 5.1 Hz, 2 H,
CHHЈ), 3.73 (s, 6 H, CH3), 4.02 (s, 12 H, CH, C5H5), 4.36 (s, 4 H,
3
C5H5), 4.60 (s, 2 H, C5H5), 4.65 (s, 2 H, C5H5), 7.19 (d, J ϭ 8.1
Hz, 4 H, C6H4), 7.42 (d, 3J ϭ 8.1 Hz, 4 H, C6H4), 7.47 (s, 4 H,
C6H4), 7.93 (s, 2 H, CH). Ϫ 13C NMR (CDCl3): δ ϭ 39.30 (CH2),
52.08 (CH3), 68.70, 68.92, 69.09, 70.79 (C5H5), 74.72 (CH), 79.34
(C5H5), 88.99, 91.04 (CϵC), 121.21, 123.06, 129.66, 131.45, 137.87,
138.55 (18 C, C6H4), 164.71 (CϭN), 171.81 (CO2).
Ϫ
C52H44N2O4Fe2 (872.6): calcd. C 71.57, H 5.08, N 3.21; found C
71.57, H 5.22, N 3.84.
1,3,5-C6H3[ -CϵC-C6H4-CH2-CH( CO2CH3) ( NϭC-Fc) ] (11):
The reaction was carried out as described for 10 with 70 mg (0.10
mmol) of the ligand of 5 as trihydrochloride trimethyl ester, 45.7
µl (0.33 mmol) of triethylamine and 70 mg (0.33 mmol) of ferro-
cenealdehyde. Yield 107 mg (84%), orange powder, m.p. 123°C (de-
comp.). Ϫ IR (KBr): ν˜ ϭ 2211 cmϪ1 w (CϵC), 1740 s (CO2), 1636
3
1.46Ϫ1.60 (m, 6 H, CH2), 1.93 (pt, J ϭ 7.9 Hz, 6 H, CH2), 3.03
3
2
3
(pd, J ϭ 5.3 Hz, 6 H, CHЈH, CH2), 3.24 (dd, J ϭ 13.1 Hz , J ϭ
3
7.0 Hz, 6 H, CHHЈ, CH2), 4.23 (pq, J ϭ 7.2 Hz, 3 H, CH), 5.00
(m, 3 H, NH), 5.79 (t, 3J ϭ 6.2 Hz, 3 H, NH), 7.16 (d, 3J ϭ 8.1
Hz, 6 H, C6H4), 7.26Ϫ7.42 (m, 36 H, C6H4, PPh2), 7.58 (s, 3 H,
C6H3). Ϫ 13C NMR (CDCl3): δ ϭ 24.97 (d, 2J ϭ 10.4 Hz, CH2),
1
2
3
s (CϭN). Ϫ H NMR (CDCl3): δ ϭ 3.15 (dd, J ϭ 14.0 Hz, J ϭ
9.0 Hz, 3 H, CHЈH), 3.34 (dd, 2J ϭ 14.0 Hz, 3J ϭ 4.6 Hz, 3 H,
CHHЈ), 3.73 (s, 9 H, CH3), 4.05 (s, 18 H, CH, C5H5), 4.36 (s, 6 H,
C5H5), 4.58 (s, 3 H, C5H5), 4.63 (s, 3 H, C5H5), 7.20 (d, 3J ϭ 8.1
Hz, 6 H, C6H4), 7.41 (d, 3J ϭ 8.1 Hz, 6 H, C6H4), 7.52 (s, 3 H,
C6H3), 7.93 (s, 3 H, CH). Ϫ 13C NMR (CDCl3): δ ϭ 39.30 (CH2),
52.30 (CH3), 68.68, 68.92, 69.10, 70.74, 70.79 (C5H5), 74.76 (CH),
79.39 (C5H5), 87.70, 90.32 (CϵC), 120.96, 123.93, 129.65, 131.66,
133.83, 138.69 (24 C, C6H4, C6H3), 164.69 (CϭN), 171.82 (CO2).
Ϫ C75H63N3O6Fe3 ϫ 1/2 CH2Cl2 (1312.3): calcd. C 69.09, H 4.92,
N 3.20; found C 68.98, H 4.60, N 3.23.
1
25.74 (d, J ϭ 18.4 Hz, CH2), 28.16 [C(CH3)3], 38.53 (CH2), 40.33
(d, J ϭ 14.9 Hz, CH2), 55.73 (CH), 80.28 [C(CH3)3], 87.99, 90.27
3
3
(CϵC), 121.42, 124.02, 128.50, 128.69 (d, J ϭ 10.3 Hz, m-PPh2),
129.52, 131.99, 132.79 (d, 2J ϭ 18.5 Hz, o-PPh2), 134.00, 137.65,
1
138.30 (d, J ϭ 13.9 Hz, i-PPh2, 60 C, C6H4, C6H3, PPh2), 155.42,
171.01 (CON).
99H105N6O9P3 ϫ 2 H2O(1654.9): calcd. C 71.98, H 6.65, N 5.08;
found C 71.77, H 6.26, N 4.77.
Ϫ δ ϭ Ϫ16.14. Ϫ
31P NMR (CDCl3):
C
General Procedure for the Preparation of the Complexes 15 and
16: To a solution of 81 mg (0.05 mmol) of ligand 14 in 10 ml of
dichloromethane were added 45 mg of [(Et3P)PdCl(µ-Cl)]2 or 46
mg of [Cp*RhCl(µ-Cl)]2 (0.075 mmol each). The solutions were
stirred at room temp. for 16 h, concentrated in vacuo and the resi-
dues were washed with 10 ml of diethyl ether and 30 ml of pentane.
1,2,4,5-C6H2[ -CϵC-C6H4-CH2-CH( CO2CH3) ( NϭC-Fc) ] (12):
The reaction was carried out as described for 10 with 51 mg (0.05
mmol) of the ligand of 6 as tetrahydrochloride tetramethyl ester,
30.5 µl (0.22 mmol) of triethylamine and 47 mg (0.22 mmol) of
ferrocenealdehyde. Yield 67 mg (80%), orange powder, m.p. 132°C
(decomp.). Ϫ IR (KBr): ν˜ ϭ 2204 cmϪ1 w (CϵC), 1739 s (CO2),
1636 s (CϭN). Ϫ 1H NMR (CDCl3): δ ϭ 3.06Ϫ3.22 (m, 4 H,
CHЈH), 3.27Ϫ3.38 (m, 4 H, CHHЈ), 3.72 (s, 12 H, CH3), 4.04 (s,
24 H, CH, C5H5), 4.34 (s, 8 H, C5H5), 4.57 (s, 4 H, C5H5), 4.64 (s,
4 H, C5H5), 7.11Ϫ7.23 (m, 8 H, C6H4), 7.39Ϫ7.48 (m, 8 H, C6H4),
1,3,5-C6H 3{CϵCC6H 4CH 2CH [ NH CO2C( CH 3) 3] [ CO2-
( CH2) 3PPh2] Pd( PEt3) ( Cl) 2}3 (15): Yield 123 mg (98%), yellow
powder, m.p. 183°C (decomp.). Ϫ IR (KBr): ν˜ ϭ 3428 cmϪ1
m
(NH), 2213 (CϵC), 1713, 1677 s (CON), 354, 329 w (PdϪCl). Ϫ
3
3
1H NMR (CDCl3): δ ϭ 0.93 (dt, JPH ϭ 17.8 Hz, JHH ϭ 7.7 Hz,
7.62 (s, 2 H, C6H2), 7.92 (s, 4 H, CH). Ϫ 13C NMR (CDCl3): δ ϭ 27 H, CH3, B), 1.16 (dt, JPH ϭ 16.5 Hz, JHH ϭ 7.5 Hz, 27 H,
3
3
39.41 (CH2), 52.42 (CH3), 68.81, 68.91, 69.15, 70.85, 70.88 (C5H5),
74.65 (CH), 79.32 (C5H5), 87.54, 95.32 (CϵC), 121.20, 125.13,
129.80, 131.77, 134.90, 138.91 (30 C, C6H4, C6H2), 164.83 (CϭN),
171.87 (CO2). Ϫ C98H82N4O8Fe4 ϫ CH2Cl2 (1752.1): calcd. C
67.86, H 4.83, N 3.20; found C 67.00, H 4.73, N 3.30.
CH3, A), 1.37 (s, 18 H, CH3, AϩB), 1.51Ϫ1.65 (m, 6 H, CH2,
AϩB), 1.81Ϫ1.95 (m, 18 H, CH2, AϩB), 2.14Ϫ2.32 (m, 6 H, CH2,
AϩB), 2.89Ϫ3.41 (m, 12 H, CH2, AϩB), 4.25Ϫ4.40 (m, 3 H, CH,
3
3
AϩB), 5.09 (d, J ϭ 6.8 Hz, 3 H, NH, AϩB), 6.52 (t, J ϭ 5.0 Hz,
3
3 H, NH, AϩB), 7.19 (d, J ϭ 8.2 Hz, 4 H, C6H4), 7.29Ϫ7.84 (m,
1796
Eur. J. Inorg. Chem. 1998, 1791Ϫ1798

Metal Complexes of Biologically Important Ligands, CVIII
FULL PAPER
39 H, C6H4, C6H3, PPh2). Ϫ 13C NMR (CDCl3): δ ϭ 8.23, 8.60
(d, 2J ϭ 1.5 Hz; 3.2 Hz, CH3, AϩB), 14.33 (dd, 1J ϭ 25.7 Hz, 3J ϭ
Giannis, T. Kolter, Angew. Chem. 1993, 105, 1303Ϫ1326; An-
gew. Chem. Int. Ed. Engl. 1993, 32, 1244.
[4] [4a]
R. M. Williams, J. A. Hendrix, J. Org. Chem. 1990, 55,
1
1
[4b]
3.1 Hz, CH2, A), 16.70 (d, J ϭ 30.4 Hz, CH2, B), 21.99 (d, J ϭ
27.8 Hz, CH2, AϩB), 24.00 (CH2, AϩB), 28.26 [C(CH3)3, AϩB],
39.20 (CH2, AϩB), 39.74 (d, 2J ϭ 14.4 Hz, CH2, AϩB), 55.64 (CH,
AϩB), 79.83 [C(CH3)3, AϩB], 87.77, 90.55 (CϵC, AϩB), 121.07,
124.02, 128.39Ϫ133.69 (m, 6 C, C6H4, C6H3, PPh2, AϩB), 133.95,
137.93, 155.12 (CON, AϩB), 170.93 (CON, AϩB). Ϫ 31P NMR
3723Ϫ3828. Ϫ
D. Ben-Ishai, J. Altman, Z. Bernstein, N.
[4c]
Peled, Tetrahedron 1978, 34, 467Ϫ473. Ϫ
S. Jaroch, T.
Schwarz, W. Steglich, P. Zistler, Angew. Chem. 1993, 105,
[4d]
1803Ϫ1805; Angew. Chem. Int. Ed. Engl. 1993, 32, 1771. Ϫ
V. A. Burgess, C. J. Easton, M. P. Hay, P. J. Steel, Aust. J. Chem.
[4e]
1988, 41, 701Ϫ710. Ϫ
G. Apitz, M. Jäger, S. Jaroch, M.
Kratzel, L. Schäffeler, W. Steglich, Tetrahedron 1993, 49,
[4f]
2
2
8223Ϫ8232. Ϫ
Th. Bretschneider, W. Miltz, P. Münster, W.
(CDCl3): δ ϭ 11.37 (d, Jtrans ϭ 538 Hz), 14.85 (d, Jcis ϭ 234 Hz),
[4g]
Steglich, Tetrahedron 1988, 44, 5403Ϫ5414. Ϫ
W. Steglich, Synthesis 1987, 223Ϫ225.
P. Münster,
2
2
25.09 (d, Jtrans ϭ 538 Hz), 30.15 (d, Jcis ϭ 234 Hz).
Ϫ
[5] [5a]
C117H150Cl6N6O9P6Pd3 (2502.3): calcd. C 56.16, H 6.04, N 3.36;
found C 56.51, H 5.95, N 3.34.
M. J. O’Donnell, R. L. Polt, J. Org. Chem. 1982, 47,
[5b]
2663Ϫ2666. Ϫ
U. Schöllkopf, U. Groth, C. Deng, Angew.
Chem. 1981, 93, 793Ϫ795; Angew. Chem. Int. Ed. Engl. 1981,
[5c]
1,3,5-C6H 3{CϵCC6H 4CH 2CH [ NH CO2C( CH 3) 3] [ CO2-
( CH2) 3PPh2] Rh( Cp*) ( Cl) 2}3 (16): Yield 123 mg (97%), orange
20, 798. Ϫ
S. Blank, D. Seebach, Angew. Chem. 1993, 105,
1780Ϫ1781; Angew. Chem. Int. Ed. Engl. 1993, 32, 1765.
H. Lei, M. S. Stoakes, K. P. B. Herath, J. Lee, A. W. Schwa-
bacher, J. Org. Chem. 1994, 59, 4206Ϫ4210.
[6]
powder, m.p. 209°C (decomp.). Ϫ IR (KBr): ν˜ ϭ 3341 cmϪ1
m
(NH), 2213 (CϵC), 1713, 1674 s (CON). Ϫ 1H NMR (CDCl3):
δ ϭ 1.29 (s, 18 H, CH3), 1.31 (s, 15 H, CH3), 1.42Ϫ1.58 (m, 6 H,
CH2), 2.47Ϫ3.19 (m, 18 H, CH2), 4.29 (pq, 3J ϭ 6.7 Hz, CH),
[7] [7a]
S. Rajagopalan, G. Radke, M. Evans, J. M. Tomich Synth.
[7b]
Commun. 1996, 26, 1431Ϫ1440. Ϫ
S. A. Metwally, H. H.
Coenen, G. Stöcklin, Bull. Chem. Soc. Jpn. 1987, 60,
[7c]
3
4437Ϫ4440.
1403Ϫ1405.
Ϫ
E. Morera, G. Ortar, Synlett 1997,
5.13Ϫ5.37 (m, 3 H, NH), 6.24Ϫ6.46 (m, 3 H, NH), 7.18 (d, J ϭ
3
7.6 Hz, 6 H, C6H4), 7.32 (d, J ϭ 7.6 Hz, 6 H, C6H4), 7.38Ϫ7.52
[8] [8a]
[8b]
G. T. Crisp, J. Gore, Tetrahedron 1997, 53, 1523Ϫ1544. Ϫ
(m, 18 H, PPh2), 7.58 (s, 3 H, C6H3), 7.69Ϫ7.86 (m, 12 H, PPh2).
`
G. Jaouen, A. Vessieres, I. S. Butler, Acc. Chem. Res. 1993,
1
13C NMR (CDCl3): δ ϭ 8.62 (Cp*), 23.48 (CH2), 26.74 (d, J ϭ
[8c]
Ϫ
26, 361Ϫ369. Ϫ
McGlinchey, A. Bennouna, A. Mousser, Organometallics 1996,
A. Gorfti, M. Salmain, G. Jaouen, M. J.
2
28.7 Hz, CH2), 28.20 [C(CH3)3], 38.68 (CH2), 39.86 (d, J ϭ 13.4
Hz, CH2), 55.34 (CH), 79.57 [C(CH3)3], 87.51, 90.69 (CϵC), 98.69
(dd, JPC ϭ 6.7 Hz, JRhC ϭ 2.4 Hz, cp*), 120.72, 124.11, 128.35 (dd,
JPC ϭ 9.8 Hz, JRhC ϭ 3.9 Hz, PPh2), 129.62, 130.89 (d, JPC ϭ 12.3
Hz, PPh2), 131.53, 133.28 (d, JPC ϭ 9.6 Hz, PPh2), 133.67, 133.92
(d, JPC ϭ 9.0 Hz, PPh2), 138.38, 155.19 (CON,), 170.01 (CON). Ϫ
[8d]
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a glass fiber and centered at 183(2) K. All reflections in the range
2 θ ϭ 13.7Ϫ49.4° (index ranges Ϫ33 < h < 33, Ϫ33 < k < 33,
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equipped with a CCD area detector. Hexagonal, space group R3,
3
˚
˚
a ϭ 28.708(5), b ϭ 28.708(5), c ϭ 14.458(3) A, V ϭ 10320(4) A ,
Z ϭ 9, d(calcd.) ϭ 1.440 Mg/m3, ϭ 3.182 mmϪ1, F(000) ϭ 4446,
independent reflections 6091 [R(int) ϭ 0.0534], 5890 observed with
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method, and the non-hydrogen atoms were refined anisotropically.
H atoms in calculated positions were included Ϫ the final refine-
ment against F2 using a riding model (SHELX93 programs). 523
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e/A close to Pt.
Crystallographic data (excluding structure factors) for the struc-
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Cambridge Crystallographic Data Center as supplementary
publication no. CCDC-102301. Copies of the data can be
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