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Graphical Abstract (Angew. Chem. Int. Ed. Engl. 171995)

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1995
International Edition in English
34/17
Pages 1779-1910
COVER PICTURE
The c o w r picture shows ii schematic representation of the arrangement in a crystal
that resembles a tartan. I t i s the expected structure for the 1 :1 adduct formed
betwcen ;I tetracationic cyclophane and ferrocene (green). The cyclophane was designed t o permit recognition both in an external and internal fashion. Indeed, the
cyclophaiic Ibrms sheets and channels in the solid state through external recognition
betwen i1.s conhtituent components. The cyclophane also complexes substrates such
;IS fcrrocenc ~ i t h i ni t s cavitj
predicted, whilst retaining the ability to form highly
structured three-dimensional arrays. i n common with the free cyclophane. Stoddart
et d . LIX I .3-bis(2-bromoethoxy)ben~eiie(red) and bipyridine (blue) as building
blocks t o ahsemble the desired tetracationic cyclophane. More about the free cycloplianc and i t s 1 : 1 fei-rocene adduct --esamples of "molecular mosaics"- are
reported on p. 1802 fl'.
REVIEWS
Contents
Extremel) high intensity pigments with extinction coefficients up to 50 times larger
than t h a t o f the industrially important pigment indigo are the red t g n - . the violet
26 n-. and the blue 34n-porphyrins shown below. For these porphyrins a linear
relationship exists between the wavelength of the most intense Soret band and the
number o f 7t electrons in the iiiacro le. With syntheses based o n those in nature.
:I Iai-gc niimbcr of expanded. bridged. inverted. and N-substituted porphyriii derivat i b e z is accessible with interesting properties for chemical and medicinal applicat I on \ .
I
20
n electrons
3(1
B. Franck.* A . Noiin
_....... ._. 1 7 Y j
~
181 1
Novel Porphyrinoids tor C'hemistrl and
Medicine by Biomimetic Sqntheses
Contents
5
Can antibody analogues be synthesized? Is it possible
to produce imprints in organic or inorganic polymers which can selectively recognize molecules? To
do just this, cross-linked polymers have been prepared in the presence of template molecules T (see
top diagram). Removal of the templates then leads
to imprinted microcavities with a definite shape and
a definite arrangement of binding groups (see bottom diagram). They can be used for chromatographic resolution of enantiomers, as chemosensors.
as artificial antibodies. as catalysts, and as enzyme
models.
G. Wulff* ...............................
fS+&z$$
1812-1832
Molecular Imprinting in Cross-Linked
Materials with the Aid of Molecular
Templates- A Way towards Artificial
Anti bodies
2 --fz
HIGHLIGHTS
A classic reaction in organometallic chemistry has
been rediscovered for organic synthesis--olefin
metathesis. In this highlight methodological studies
and the more recent impressive synthetic applications are described. The total synthesis of fluvirucin
B, aglycon (1) by A. H. Hoveyda is one of the latest
impressive achievements.
H.-G. Schmalz* ....__.._...._......
1833-1836
Ye
OH
Et
"'
Catalytic Ring-Closing Metathesis: A New,
Powerful Technique for Carbon-Carbon
Coupling in Organic Synthesis
HN
1
The current world record for the largest tilt angle in a [llferrocenophane is held by
complex 1 ; no [l]metallocenophanes have been prepared with a bridge smaller than
the sulfur atom here (I. Manners et al. A n g m . Chem. In[. Ed. Engl. 1995,34. 1506).
The greater the ring strain in metallocene derivatives, the more readily they polymerize giving compounds like 3, which IS formed from 2 by desulfurization with phosphane. Since the metal atoms in these polymers are arranged in a regular sequence,
interesting material properties are anticipated.
i
M. Herberhold* ....................
1837-1839
Distorted Sandwich Compounds:
[1]Ferrocenophanes and
[2]Ruthenocenophanes
3
2
COMMUNICATIONS
A mixture of different conformers of the flexible tetrasaccharide sialyl Lewis" is
presented in solution to the E-selectin receptor, which binds only one conformation,
as shown by N M R spectroscopy. The experimentally determined transfer NOES can
be used to derive proton-proton distance restrictions, which together with the
conformer ensemble obtained by Metropolis Monte Carlo simulations, can be used
to determine the conformation of sialyl Lewis" in the complexed state.
~
0
-
OH
AcNH
HO
&
7
O(CH,)8COOMe
NHAc
K. Scheffler, B. Ernst, A. Katopodis,
J. L. Magnani, W. T. Wang, R. Weisemann,
T. Peters* ..............................
1841 -1844
Determination of the Bioactive Conformation of the Carbohydrate Ligand in the
E-Selectin/Sialyl Lewis" Complex
Contents
The catalytic C-C coupling of chloroarenes by both
y 3
the Heck and the Suzuki reactions has been achieved
?p,R O A O
for the first lime with new palladacycles of type 1, in
which R can be, for instance, o-tolyl or niesityl.
0-0
.p,
They are a n order of magnitude more active than
Y R F I
conventional catalysts and. moreover, thermally
CH3
considerably more robust. But above all. the cleav1
age of the P C bond and the deposition of palladium is not observed. Analogous reactions with bromoarenes can also be catalyzed to advantage with 1. The Heck reaction of haloarenes with vinyl derivatives (e. g., n-butyl acrylate) gives (E)-styrene derivatives in one
step. In the SuIuki reaction the haloarenes are converted into biphenyl derivatives
with phenylboronic acid. also in one step.
W. A. Herrmann,* C. Brossmer, K . Ofele,
C.-P. Reisinger, T. Priermeier. M. Beller,
H. Fischer .............................
1844-1 848
The transition to the carbanion is represented by the structure of the carbenoid 2,
which is accessible from 1 . The solid-state structures of 1 and 2 have been determined. Compound 2 is converted into the phosphirene 3 by elimination of LiCI.
E. Niecke,* P. Becker. M. Nieger,
D. Stalke, W. W. Schoeller ..... 1849-1852
a +,m
C1
I
Aryl -P
/-”
\CR
1
-
c1
//”I --Li(thf)g
Awl-P
/I’
u Ary1-p
2
PPh3
x
’c;PPh,
2
Carbenoid or Lithium Complex of ii
Carbanion? Synthesis and Structure
of (Me,Si)2C = P(aryl) = C(Cl)Li(thf), and
LiCl Elimination To Give the Phosphirene
H.-P. Schrodel, G. Jochem.
A. Schmidpeter.* H. Noth .... 1853-1856
Ylidediyl
Halophosphane
Oligomers.
(Ph,PCPX), -A Structurally Diverse Class
of Compounds
~
PPh,
X
1
Palladacycles as Efficient Catalysts for Aryl
Coupling Reactions
‘R
3
+
‘ P L J
M. Beller.* H. Fischer, W. .A. Herrmann,
K. Ofele, C. Brossmer ........... 1848- 1849
c
‘
\CR,
More electron-rich, and displaying a greater diversity of structures and a greater
tendency to dissociate than the cyclophosphazanes. the members 1-3 of’the new
oligomeric family from the Ph,PC/PX combination. isoelectronic to RN/PX. have
the longest P X bonds yet observed. X = Br, CI.
x
Palladacycles as Structurally Defined Catalysts for the Heck Olefination of Chloroand Bromoarenes
3
.,;;t’P-X
p b f 3 p
Ph,P
A PPh,
x-
K . H. Dotz.* W. Straub. R. Ehlenz.
K. Peseke, R. Meisel ............. 1856-1858
Stereoselective functionalization of carbohydrates
may be possible with sugar--carbelie complexes 1, in
which the C-l atom is modified to be a metal-coordinated carbene. This results in an increase both of
the electrophilicity of C-1 and the acidity of the adjacent C H group. M = Cr, Mo, W. s = 5 : M =
Fe. \ = 4.
Carbene Complex Functionalized Sugars
Ac
~
By using “naked” fluoride ions in the form of tetramethylammonium fluoride or
hexainethylpiperidinium fluoride, the fluorocarbonate (fluoroformate) [FCO,]- can
be synthesized. This anion has an extraordinarily weak C - F bond. It was characterized by ‘Y. solid-state NMR. IR, and Raman spectroscopy, as well as by a b initio
calculations.
X. Zhang, U. Gross,
K. Seppelt * ...........................
Held together by twelve Ni-C and two Xi-Ni bonds.
and stabilized by intra- and intermolecular hydrogen bonds. the title compound 1 is the first member
o f the hitherto hypothetical series [M,(alkyne),+ ,]
( M = d l o system). Complex 1 contains a bent Ni,
chain ( 1 18 ) and is stable at room temperature.
D. Walther.* T. Klettke.
H . Giirls ................................
6963
I
\
@-&\
@\
+\
I
/*-@
a, I
/@’
C(CH, ),
7
@
@
1, R ’ =
/@
,
Hi =
C(CH, ),OH
1858 -- 1860
Fluorocarbonate, [FCO,]- : Preparation
and Structure
1860-1861
[Ni,(alkyne),] The First Homoleptic
Alkyne-Metal Oligonier (Alkyne: 7.5.5Trimethylhex-3-yn-2-01)
Contents
Highly ordered two-dimensional sheets sustained by
x-donorin-acceptor interactions and the ability to
form an inclusion complex with ferrocene with only
minimal changes in crystal packing are the outstanding features of the macrocyclic tetracation I .
This cyclophane can be prepared in two steps from
bipyridine and the dibromide 2.
P. R . Ashton, C. G. Claessens.
W. Hayes. S. Menzer. J. F. Stoddart,*
A. J. P. White, D. J. Williams ... 1862.- 1865
/o*o>
8
+N
$
+
1
Molecular Mosaics Formed by a Square
Cyclophane and Its Inclusion Complex
with Ferrocene
+
LO-QOJ
2
Br”O-@-O”Br
P. R . Ashton, P. J. Campbell.
E. .I. T. Chrystal, P. T. Glink, S. Menzer,
D. Philp, N. Spencer. J. F. Stoddart,*
P. A. Tasker, D . J. Williams .. 1865-1869
R
A simple motif for molecular recognition--the binding of disubstituted ammonium salts. for example
dibenzyl- and di-n-butylammonium hexafluorophosphate. with crown ethers like dibenzo[24]crown-8--results in the self-assembly of threaded 1 : 1 complexes I . The superstructures of these
complexes are stabilized by hydrogen bonds, electrostatic pole- dipole interactions. and dispersive interactions.
PF,-
Dialkylammonium 1on:’Crown Ether Complexes: The Forerunners of a New Family
of Interlocked Molecules
R
1. R=PhCH ,iBu
Novel supramolecular architectures formed by selfassembly of three or four charged and neutral species have been prepared and characterized. In both
the solution and solid states the tn’o dibenzylammonium ions in the dicationic 1 : 2 complex I are
threaded
siinultaneously
through
bis-powphenylene[34]crown-l0. This macrocyclic polyether
forms a 2 : 2 complex with ;c,cc’-bis(benzy1ammonium)-/~nr.rr-xylylenebis(hexaflu0rophosphate) in the
solid state.
P. R. Ashton, E. J. T. Chrystal. P. T. Glink.
S. Menzer. C. Schiavo. J. F.Stoddart,*
P. A. Tasker. D . J. Williams ... 1869--1872
Ph
Doubly Encircled and Double-Stranded
Pseudorotaxanes
Ph
1
By wrapping the inorganic core of the
cluster with hydrocarbons (Cp* substituents of the Cp*TiF2 building
blocks), the very large dimetallic aggregates 1 (core of cluster shown on
the right) and 2 can be dissolved in
organic solvents. I11 this way a source
of “soluble N a F and CaF2” in common solvents is available for
organometallic chemistry. Compounds 1 and 2 are obtained froin
the reaction of [Cp*TiF,] with Na!’
Hg and Ca;’Hg alloy, respectively.
[C~T,Tii,Nai,F,,(tht),l
1
F.-Q. Liu. D. Stalke.
H. W. Roesky * _..___.......__....__.
1872-1874
(C,Me,)TiF,--A
Versatile Building Block
for Generating Large Soluble Dimetallic
Aggregates
.
[(Cp*TiFz),CaF2(tht))212
1H,1 5 N correlated NMR spectroscopy has proven to be a suitable method to investigate the reaction of the anticancer drug cisplatin C ~ . S - [ P ~ C ~ , ( N H
] DNA.
( I,)) ~
with
All the intermediates in reactions of I with complementary model oligonucleotides
can be detected with this method; one of these intermediates is shown.
NH3
I
HZN-Pt-CI
5’-d(A
I
- C - A - T - G - G - T - A - C - A)
K . J. Barnham. S. J. Berners-Price.
T. A. Frenkiel, U. Frey.
P. J. Sadler * ..........................
1874- 1877
Platination Pathways for Reactions of
Cisplatin with G G Single-Stranded and
Double-Stranded Decanucleotides
-. -~
c'o n tc n t s
-
.4 new class of octahedral zirconium cluster compounds containing only halide and hydride ligands is
described. These contain the anions [Zr,X,,H,]"o r [7r~,X181H5]'(shown on the right). The hycirogen atoms arc randomly disordered on positions in
o r very near to the centers of all the triangular faces
ofthc Zr,, ocl:ihcdron according to X-ray crystallog-
L. Chen. F. A. Cotton.*
W. A. Wojtczak ....................
The [Zr,X,,H5]'- Ions uith X
and Related Species
1877 1879
=
C1, Br.
raph?
The tellurometalate ions [GaTe,[-'- and [ln,Te,15hu\r been prepared by chemical reduction of
GalTe, and In,Te,. respectively. by potassium in
liquid N H , in the presence of an encapsulating ligand. The [GaTe,]' ion is essentially trigonal planar: the [In,Tc-]'- ion is cuboidal. where one corner
is iiiishing (h(ixcture shown o n the right). These anions h a v e no counterparts in S or Se chemistry.
Salm,
C.-W. Park. R . .I.
.I.A. Ibers * ..............................
1879 .. 1880
New Tellurometalates of Gallium a i d Indium : K[K([I 8]~rown-h)]~[GaTc,]
. ? CH ,CN
and [(NEt,),][In,Te-].O.S E:.tZO
Te
Te
L. Ernst.* K . Ihroin
Fine tuning of the nonbonding F-F distances. by
bridge length \ariation and suitable substituents. in
a series of difluorometa- ( 1 ) and -paracyclophanes
led to ;I nebv cluantitative description of distance-dependent lL)F.l"F
through-space spin-spin coupling.
This will be useful for structural studies of di- and
oligolluoi-iti~itedcompounds in solution.
..............
1881 - ~ 1 8 8 1
A New Quantitative Dexription of the
Distance Dependence of' Through-Space
"F. 'F Spin Spin Coupling
-
R
I
R = H, /Bu
Z = CH,CH,, CH,SCH,
32- and 34-membered macrocyclic Schiff base type
ligands with (N2S,), donor units are synthesized in
a high-yielding [2 + 21 condensation reaction. Coordination of these ligands to copper(r) results in double helical dicopper(1) complexes with a new figureof-eight loop structure (see diagram on the right).
P.Cornba,* A. Fath. T. LV. Hambley.
D. T. Richens* ......................
1883 1885
s'
\
Double Helical Dinuclear C'opper(1) Complexes of Macrocyclic Bis(dithiadiimine)
Ligands
1
The guest decides which host is formed! This was the result of studies with the
compounds 1 and 2, which form the adducts 1-1. 2-2, or 1-2 in solution. depending on thc molecular size of the solvent molecule. R = C 0 2 E t .
w
R
w
0
1
H
S
T
N
J
- 1
R
0
1
Q:=q&-
HNKN
0
A highly non-aromatic structure is exhibited by the
free germacyclopentadienide ion (shown on the
right) i n the Li([l?]crown-4), salt. The angle between thc C',Cie plane and the Ge-Si bond is 100.2 .
Calculationj at the R H F level of theory on
(C4H,GcSiH3)- accurately reproduce the observed
geometrical parameters. and predict that the
analogous Si and Sn derivatives would also have
highly pyrumidalized structures.
Pseudo-Spherical Host Molecules: Synthesis. Dimerization. and Nucleation Effects
1
N
K0
HN
C. Valdes, U. P.Spit7. S. W. Kubik,
J. Rebek Jr. * ........................
1885-1887
2
W. P. Freeman. T. D . Tilley.*
F. P.Arnold. A. L. Rheingold,
P. K. Gantzel
Synthesis and Structure or ;I Free Gerniacyclopentadienide Ion:
[Li([1 2jcrown-4),][C4Me,GeSi( SiMe,),]
Contents
Planar and highly polarizable. the dianionic thiocarbon 1 reacts with metal salts to
give inorganic polymers like [Cu,C,S,J and [NiC,S,] with semiconductor properties.
The Ni coordination polymer forms a one-dimensional ribbonlike strand of edgesharing square-planar complexes such as 2.
L. F. Szczepura, C. P. Galloway, Y Zheng,
P. Han, A. L. Rheingold, S. R. Wilson,
T. B. Rauchfuss* __....._...___.....
1890-1892
C,Si- : A Bridging Bis(dithio1ato) Ligand
for the Preparation of Semiconducting
Inorganic Polymers
2
1
An intramolecular pinacol coupling and subsequent reduction were the key steps in
the construction of the 14-membered ring of dione 1. Depending on the substituent
R, the new dehydroannulenes 2 (R = H, Ph, tBuC,H,, OSiMe,tBu) can be prepared
by different methods. These compounds display considerable aromaticity despite
only nominal stability.
Two interlocking Au, rings, whose individual
metal atoms are linked through ethynyl ligands,
are present
in
the
title
compound
[{Au(C= CtBu)),], . This novel homoleptic
organometallic ['Icatenane spontaneously selfassembles in the reaction of [Au(NH,),JBF, with
iBuC-CH. Weak Au-Au interactions may
contribute to the self-assembly of the structure.
The bonding in one ring is shown schematically
on the right.
+77
I
'Au
4
111
\
77'
111,
77
I
q2
@Ah,
q*
2
A Gold(i) [2]Catenane
Au @
I
77 - A u - q 1 8
r2'
0
The silver salts AgPF, and AgSbF,
react with pyrazine to give unprecedented networks of two- and threedimensional cubic units. The PF;
derivative has a layered structure,
whereas the SbF; derivative (shown
scheinatically on the right) contains
a simple cubic frame of the I-polonium type.
Together, hydrogen sulfide and iron(ii1) sulfide mediate the reductive coupling of
farnesol giving squalene (l), albeit in low yield. This finding is interesting, because
the reducing system H2S/FeSplays a central role in the theory of the "pyrite-driven"
prebiotic world, and squalene is present in all organisms.
1
Synthesis of New Sworski-Type Dehydroannulenes: 3,4-Benz-1,2,5,6.8,9,12,13octadehydro[ 14Jannulenes
D. M . P. Mingos,* J. Ym, S. Menzer,
1894-1895
D. J. Williams ._.__._...........__....
- A u0 - ' ~1 ~~2
A~'
Y. Kuwatani,* I. Ueda .......... 1892-1894
L. Carlucci, G. Ciani,* D. M. Proserpio,
A. Sironi ...............................
1895-1898
Novel Networks of Unusually Coordinated
Silver(1) Cations: The Wafer-Like Structure
of ~A~(PYz),l[Ag,(PYz),I(PF,), .2G and the
Simple Cubic Frame of [Ag(pyz),](SbF,)
M. Keller, D. Hafenbradl, K. 0. Stetter,
G. Teller, Y Nakatani,
G. Ourisson * ......_____.............
1898-1900
A One-Step Synthesis of Squalene from
Farnesol under Prebiotic Conditions
+
Electron transfer induction enables [4 21 cycloadditions of 2-vinylindoles I with
electronically similar dienophiles such as 2. The reaction of 1 and 2 furnishes the
alkaloid skeleton 3 with highly stereoselectivity. SET = single electron transfer.
C. F. Gurtler, S. Blechert.*
E. Steckhan ...........................
1900-1901
Radical Cation [4+ 21 Cycloadditions with
2-Vinylindoles
1
2
* Author to whom
correspondencc \hould be addresaed
BOOKS
Two Dimensional NMR Spectroscopy. Applications for Chemists and Biochemists .
W. R. Croasinun. R. M . K. Carlson
J. Lauterweiii ...................................
1903
Ferrocenes. Homogeneous Catalysis. Organic Synthesis, Materials Science
A. Togni. T. Hayashi
H . Plenio .........................................
1904
The Chemistry of Fullerenes . A. Hirsch
B. Kriiutler ......................................
1904
Events 1832
Keyword Index 1906
Author Index 1907
Chemistry--A European Journal may be found after page 1908 with its
own table of contents and separate pagination.
Preview 1908
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