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Graphical Abstract (Angew. Chem. Int. Ed. Engl. 181994)

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A Journal of the
GeselIschaft
Deutscher Chemiker
1994
33/18
-
International Edition in English
Pages 1787 1894
COVER PICTURE
The cover picture shows a complex composed of 16 Pb2+ ions (in blue) and two
16-fold deprotonated y-cyclodextrin tori (0atoms in red), in which each alkoxide 0
atom bridges two Pb atoms. An eight-point star of P z + ions results; the diolate
residues face each other, and the inner Pb2+ ions have 4 + 2 coordination. The
complex is formed in the presence of a substoichiometric amount of P b Z + ,which
hints at a cooperative mechanism of formation. P. Kliifers and J. Schuhmacher
report more on this attractive first member of a long-neglected class of compounds
on p. 1863 ff.
REVIEWS
Contents
Dirhodium(i1) complexes, in particular, catalyze the reactions of a-diazo carbonyl
compounds (e.g. 1). The rhodium(r1) carbenoids formed as intermediates can undergo reactions such as cyclopropanation and insertion into C-H bonds (for instance,
formation of 2 or 3; cap = caprolactamate, pfb = perfluorobutyrate). Mechanistic
interpretations account for the results of the rich chemistry.
R>
"'Ph
IRh~(cap)41
AH
[RhZ(Pfbi41,
0
0
2
3
1
3
A. Padwa,*
D. J. Austin ........_...__.______.__......
1797 1815
Ligand Effects on the Chemoselectivity of
Transition Metal Catalyzed Reactions of
a-Diazo Carbonyl Compounds
0
An ideal probe for testing models of the atmosphere, the OH radical is produced
primarily by the photolysis of ozone. Some of its subsequent reactions are cyclic
processes involving CO, CH,, and NO,, in which OH radicals are regenerated. For
this reason the OH concentration is a sensitive measure of the composition of the
atmosphere; however, its determination is also a significant challenge for analytical
chemists.
F. J. Comes* ..........................
1816--1826
Recycling in the Earth's Atmosphere:
The OH Radical-Its Importance for the
Chemistry of the Atmosphere and the
Determination of Its Concentration
HIGHLIGHTS
Contents
A much broader range of applications for antibody techniques should result from a
new method that allows the production of a large quantity of diverse antibodies
without the immunization of animals. Expression on phage surfaces is used to
produce antibodies that recognize double-stranded D N A with specificity. This is but
the latest demonstration of the tremendous potential of antibody methods.
Chemistry under extreme conditions makes the synthesis of 1 and 2 possible. AlBr is
formed by cocondensation of Al atoms and HBr and trapped with different reagents
and at different temperatures to yield the first donor-stabilized aluminum(1) and
aluminum(i1) halides isolable at room temperature.
Br
L'
L'
M. Famulok,*
D. Faulhammer .....................
1827-1829
Specific Binding of Antibodies to D N A
through Combinatorial Antibody Libraries
J. J. Schneider* .......................
1830-1832
Subvalent Aluminum Halides as Examples
of High-Temperature Species in Inorganic
Syntheses
Br
Difficult, but not impossible! Though anions are
large and coordinatively saturated-and therefore slow to form adducts- -they do form complexes selectively and efficiently with the novel
coronands and cryptands specially tailored to
be large enough and to contain ionic, Lewis
acidic. or dipolar groups. These host molecules
can be, for instance, modified carboranes and
crown ethers or tricyclic borane-amine adducts (as in the formation of 1).
D . E. Kaufmann,*
A. Otten .................................
./p(,@
1832-1834
The Search for Selective, Neutral Anion
Receptors
~
COMMUNICATIONS
Optically pure (&)-(-)-1 ([a];' = -210) can be
liberated from a configurationally homogeneous
palladium(n) complex containing the phosphane
and ortho-metalated (R)-(-)-[l -(dimethylamino)ethyllnaphthalene. The phosphane racemizes over
6 h at 20 "C without significant disproportionation.
0
anion '+N--B*,~H
1 e,H'tl
X\<'e
@
's"
4%
..
M. Pabel, A. C. Willis.
S. B. Wild* ............................
I S
1835-1837
.P
f]
p'h
(SP) -
(-1
First Resolution of a Free Fluorophosphane Chiral at Phosphorus
i Pr
-1
F. Derguini,* K. Nakanishi,
J. Buck, U. Hiimmerling,
F. Griin ..................................
A prevalent metabolite and antagonist of retinol, all/ram-anhydroretinol 1 is found in the liver and lung
cells of mammals and in cultivated insect cell lines.
This compound is particularly important owing to
its reversible inhibition of the growth and proliferation of immune cells. The characterization of 1 isolated from Drosophilu cell line S2M3, and several of
its synthetic isomers is described.
1837-1839
Spectroscopic Studies of Anhydroretinol,
an Endogenous Mammalian and Insect
retro-Retinoid
Y. Naruta,* M. Sasayama,
T. Sasaki ................................
A functional model for the tetranuclear manganese
cluster in the photosystem I1 of higher plants and
cyanobacteria is now provided by binuclear dicationic manganese complexes such as 1 . In the
anodic oxidation of aqueous acetonitrile containing these complexes water is oxidized to oxygen
by a four-electron process. An example of Ar is
4-[BuC,H,; counterion ClO,.
1839-1841
Oxygen Evolution by Oxidation of Water
with Manganese Porphyrin Dimers
1
Ar
Face-sharing tetrahedra arranged in a helix (idealized form shown below) mark the
structure of the iodocuprate 1, which was obtained from Ph,PI, I,, and Cu. Five Cu
positions were identified at room temperature; at lower temperatures only three
(slow cooling) or four (rapid cooling) are occupied.
(Ph,P),’ICu,l,l
H. Hartl,*
F. Mahdjour-Hassan-Abadi .. 1841 1842
-
[(C,H,),P] f[Cu,I,]--The
First Compound with a Helical Chain of FaceSharing Tetrahedra as a Structural Element
1
With a judicious choice of tether from the “chiral pool”, coupling of the two aryl rings
in nonracemic 1 yields only one of the two possible diastereomers of biaryl2. G = C
or 0 substituent; R. R‘ = H, 3OMe. This method is expected to be widely applicable.
R
G
2. cyanocuprate
formation
.
.
Asymmetric Synthesis of Biaryls by
Intramolecular Oxidative Couplings of
Cyanocuprate Intermediates
R
1. dilithiation
B. H. Lipshutz,*
F. Kayser, Z.-P. Liu ............... 1842 1844
oxidation of
*
R‘
R or S,depending
nonracemic
bridge
on bridge
2
I
A new lead structure for the synthesis of trehalase inhibitors, salbostatin (l), is
described. In one of the few systematic investigations into microorganism cultures,
this pseudodisaccharide and a second metabolite 2 were isolated from the culture
supernatant of a long-term fermentation. Trehalase inhibitors such as 1 are important compounds in the area of plant protection.
Ov&H~y
HOCHZ
HOCH,
@-;HZ-CH(OH)-CH~OH
L. Vertesy,* H.-W. Fehlhaber,
1844- 1846
A. Schulz ...............................
The Trehalase Inhibitor Salbostatin, a
Novel Metabolite from Strep!orn.rces cilhus.
ATCC21838
3’
1
HO
HO
OH
H
2
NH2
The first diarylstannylene monomeric in the solid state and not stabilized by donor
ligands is 1. The dark red compound forms in good yields from Sn[N(SiMe,),], and
RLI ( R = 2.4,6-rBu,C6H2). In solution 1 apparently isomerizes to give the sterically
less encumbered stannylene RR’Sn: (R’ = CH,C(Me),-3,5-rBu,C,H3).
M. Weidenbruch,* J. Schlaefke,
A. Schiifer, K. Peters,
H. G. von Schnering,
H. Marsmann ........................
1846- 1848
Bis(2,4,6-tri-tert-butylphenyl)stannanediyl:
I Bu
H
C
,
,
Simple, mild, and enantioselective! Oxygen reacts with ketone 1 in the presence of pivalaldehyde ( R = tBu) and a chiral copper complex
(cat.*) to give lactone 2 in 47 YOyield and 69 %
w . Other enantioselective Baeyer-Villigertype oxidations had previously only been
achieved with the help of enzymes.
*
1
Ar
(Rj-2
rac.~
An 0 + C silyl group migration is the surprising result of the reaction of the Cp,Zr precursor 1 with the
bis(trimethylsilyl) acetylenedicarboxylate to give 2.
In contrast, with the analogous di-terf-butyl ester, a
zirconadihydrofuran forms under alkyne dimerization. The participation of CO groups should be taken into consideration in the application ofthe metallocene-induced cyclization of alkenes and alkynes.
[Cp,Zr O ~ C M e zC(SiMe,)=C(SiMe,)]
6
Oz.RCH0,
Kat.* (1 Mol-%)
Me3Si02C \C”C
CP2zr.o/
I
YMe3
0 2 cP
c--o
\ Y P ,
C
‘,
I
Me3Si
\C02SiMe,
C. Bolm,* G. Schlingloff.
K. Weickhardt .......................
1848 - 1849
Optically Active Lactones from a BaeyerVilliger-Type Metal-Catalyzed Oxidation
with Molecular Oxygen
U. Rosenthal,* A. Ohff,
W. Baumann, R. Kempe,
A. Tillack, V. V. Burlakov ._._..1850-1852
\
‘ I
A Diarylstannylene without Donor
Stabilization
2
Unexpected Reactions of Acetylenedicarboxylates with Zirconium Complexes
Not an insoluble sulfide, but the homoleptic gold complex 1, which is stable without
any auxiliary ligands, is formed in the reaction of bis(acetylacetonato)gold(I) with
hydrogen sulfide [Eq. (a)]. Complexes of this type are of interest as intermediates
in the catalytic hydrodesulfuration of organosulfur compounds. Counterion:
[(Ph,P),NI+
- 2 Hacac
-[HS-Au-SH]-
PJ
+
Me
2H,S
J. Vicente,* M.-T. Chicote.*
P. Gonziilez-Herrero,
P. G. Jones, B. Ahrens ........... 1852-1853
A Postulated Carrier of Gold in Hydrotherma1 Ore Solutions: Synthesis and Crystal
Structure of [(P~,P),NI[AU(SH)~],
the First
Homoleptic Hydrogensulfido Complex
(a)
1
Me
The three-membered ring of cyclotrisilane 1 is almost undistorted. This is a result of
the only moderate steric bulk of the 2-(dimethylaminomethyl)phenyl ligand. which
also dictates the unexpected synperiplaiiar conformation of disilene 2.
J. Belzner,* N. Detomi,
H. Ihmels,
M. Noltemeyer ......................
1854-1855
Structures of 2-(Me,NCH,)C,H,-Substituted Oligosilanes
2
1
A substitute for the CO ligand in the form of an electron-poor, chiral phosphorus
ligand can be used to synthesize efficient transition-metal catalysts for asymmetric
Diels-Alder reactions. In the presence of 2, for example, r-bromoacrolein reacts
with cyclohexadiene to form I in > 9 9 % ee.
ca
1
1
k
D. R . Gardner.
J. C. Fettinger,
B. W. Eichhorn* ....................
Synthesis and Structure of [W0Te,l2-
I
I
@W
1859- 1860
Te(2)
Fragments 3 and 4 are formed selectively upon irradiation of 2 in aqueous solution.
This proves that sites of DNA strand scission can be designated by incorporation of
1 in oligonucleotides.
B. Giese.* A. Dussy, C. Elie.
P. Erdmann,
U. Schwitter ...........................
1861-1863
Synthesis and Selective Radical Cleavage of
C-4'-Modified Oligonucleotides
3
0
m-po-
0
Lv
1
Asymmetric Diels-Alder Reactions
Catalyzed by a Chiral Iron Lewis Acid
2
Three terminal tellurido ligands in one complex-this
is the closest approach to homoleptic [MTe,]"- ions
to date. The telluridotungstenfvr) complex 1 was
obtained from the reaction of [W,(O,CC,H,),] with
K,Te,. The prospects for [MTe,]"- complexes are
not so bad after all.
OAe
1856- 1858
I
Br
1
E. P. Kiindig,* B. Bourdin.
G. Bernardinelli .....................
0
--
11-
n
A@
2
1792
1
'C VCH VErlrr~.\ge.srlls~h~ifi
mhH, D-69451 Wr.inheim, I994
0570-0833:94:1818-1792 S 10.00+ .25:0
An,qcw. Chrm. In!. Ed 0 ~ ~ 1994,
1 . 33. No. I8
i>
Even in neutral, aqueous solution, carbohydrates are
deprotonated in the presence of appropriate metal
ions. The particularly attractive structure of 1
(right; the lines represent diolato bridges and the
circle the cyclodextrin torus) illustrates this principle, which has hitherto escaped attention most
probably because the initial precipitates were mistaken for the metal hydroxides.
- 16H-),] . 20H,O
[Pb,,(;.-cyclodextrln
P. Klufers,*
J. Schuhmacher ......................
1863- 1865
Sixteenfold Deprotonated y-Cyclodextrin
Tori as Anions in a Hexadecanuclear
Lead(rr) Alkoxide
1
A tangle of threadlike carbon polymers, which do not form two-dimensional layers,
was observed in the transmission electron micrograph of the fullerene black produced in an electric arc. Curved polycyclic layer structures were also formed. Both
of the suggested mechanisms for fullerene formation-via small rings, which then
condense, or via macrocycles, which then isomerize- -thus seem possible. Which of
the two dominates depends on the reaction conditions.
T. Belz, H. Werner, F. Zemlin,
U. Klengler, M. Wesemann,
B. Tesche, E. Zeitler,
A. Reller, R. Schlogl* ........... 1866- 1869
Amphotropic interactions and favorable steric conditions result in the formation of
liquid crystalline phases from complexes of polyacrylic acid with cationic surfactants. I n these phases, the polymer chains are intertwined into a multichain structure
(shown below). These complexes form by self-organization, and have interesting
optical and mechanical properties.
M. Antonietti,*
J. Conrad ...............................
Combined in situ fluorescence X-ray absorption and
X-ray diffraction have enabled the characterization
of active centers of a Co-doped aluminum phosphate catalyst under near-operational conditions.
Normally the characterization is carried out under
rather artificial conditions, with the catalyst in
either an expired (postmortem) or precursor (prenatal) state. Thus, structure A was determined for
the local Co environment of the active catalyst.
J. M. Thomas,* G. N. Greaves,*
G. Sankar, P. A. Wright,
J. Chen, A. J. Dent,
L. Marchese ...........................
1871-1873
H
OHOTs
.
O
TsO O HWOH
1
0
- H0
1
Synthesis of Most Highly Ordered Liquid
Crystalline Phases by Complex Formation
of Polyacrylic Acid with Cationic
Surfactants
H. Wagner.
U. Koert * ..............................
1873-1875
A Multiple Five-Membered-Ring-Selective
Williamson Reaction as a Key Step in the
Stereoselective Construction of 2,SLinked
Oligo(tetrahydrofuran)s
H
2
Polyamidoantimony anions are durable and effective
ligands, as illustrated by the synthesis of 1 from 2
and CuCI. The Cu, framework of 1 is essentially
square planar. The cyclohexyl (cy) substituents have
been omitted from the picture shown on the right.
[(Sb,(Ncy),l 2CwJ
~
A
--f
.
1869 1870
On the Nature of the Active Site in a
CoAPO-18 Solid Acid Catalyst
Four tetrahydrofuran rings in one step can be constructed with the multiple five-membered-ring-selective Williamson reaction (1 2). The tetratosylate 1 is obtained
from the corresponding dialkyne by a reagent-controlled, diastereoselective dihydroxylation. This reaction sequence opens up an efficient route to enantiomerically
pure oligo(tetrahydrofuran)s.
Ts?HQ
On the Mechanism of Fullerene Formation
[ISb,(Ncy),J,Li,l
D. Barr, A. J. Edwards, S. Pullen,
M. A. Paver, P. R. Raithby,
M.-A. Rennie, C. A. Russell,
D. S. Wright* ........................
2875-1876
[{ Sb,(Ncy),),Cu,] : A Mixed-Metal
Antimony(nr)/Copper(r) Complex
Containing a Cu, Square Plane
2
1
/
Ring strain does not destabilize Fe"' ( I ) and Cr"'
complexes with $-bound triazacyclohexdne ligands. In the Cr"' complex with isopropyl substituents on the nitrogen atoms. two chloro ligands
were readily exchanged for CH,SiMe, groups.
Thus, the easily accessible triazacyclohexanes may
serve as sterically less demanding alternatives for
triazacyclononane ligands.
'N-N-
P
N
R. D. Kohn,*
G . Kociok-Kohn ....................
7
\ Fe
1877-1878
1
c, .++'j
++,c,
Cr"' and Fe"' Complexes with
q3-1.3,5-Triazacyclohexane Ligands
CI
Owing to the steric bulk of the teut-butyl groups, the reactivity of the novel porphyrin
I. which has a nonplanar macrocyclic framework, deviates distinctly from that
of any other known porphyrin. For example, prolonged treatment of I in
HCl0,iMeOH leads to formation of 5,15-dihydroporphyrin ("porphodimethene") 2.
T. Ema, M. 0. Senge,
N. Y Nelson, H. Ogoshi.
K. M. Smith* ........................
1879-1881
5.1 0.15,2O-Tetra-trrt-butylporphyrinand
Its Remarkable Reactivity in the 5-and
15-Positions
Me?,,
HC104/MeOH
-$Ie
Me
M&
Me
2
1
A novel centrosymrnetric chairlike conformation of
the central Rh,S, framework (shown on the right) is
present in the title compound. The D,,-symmetric
S, ligand shows the bonding characteristics of cyclobutadiene, but its structure resembles that calculated for the free neutral S, molecule. This ligand is
stabilized by the two Rh-Rh bonds.
s--........s
I
. Cp'. JL ~ y h C p '
The triplet lifetimes of the ethynyl-bridged binuclear Ru" complexes 1 (rn = 0. 1 ;
17 = 1, 2) are significantly longer than that of the parent mononuclear complex,
despite much lower triplet energies. This effect, which arises from electron delocalization over an extended n* orbital, decreases upon removal of the second Ru"
cation or if phenyl rings are incorporated into the n-electron system. Counterion:
PF, .
K. Isobe,* Y Ozawa,
A. Vazquez de Miguel,*
T.-W. Zhu, K.-M. Zhao,
T. Nishioka, T. Ogura,
T. Kitagawa ...........................
1882-1883
[(Rh,Cp~(pCH2)Z)Z(p-S,)]2t
: A Novel
Tetranuclear Cationic Complex with a
Rectangular S, Unit
A. C. Benniston,
V. Grosshenny,
A. Harriman,*
R . Ziessel" .............................
3 884-1885
(
F
&
4+ M&>
-
N\
/
N\
-
/
m
n
m
N
-
N-
\ /
Electron Delocalization in Ethynyl-Bridged
Binuclear Ruthenium(rr) Polypyridine
Complexes
N-
\ /
1
The bis(p-phenolato)diiron(rr) complex 1 is a model
compound for nonheme iron enzymes that use x-keto
acids as cofxtors. Complex 1 undergoes immediate
oxidative decarboxylation upon exposure to dioxygen at a rate which is three to four orders of magnitude faster than those observed for other compounds of this type. The formula of the ligand is
given under that of I .
1794
Y.-M. Chiou,
L. Que, Jr.* ............................
1886-1888
4 Model for x-Keto Acid Dependent
Nonheme Iron Enzymes: Structure and
Reactivity of [Fe:'(Me,hdp),(bf)](C104)
0
[(C,NH,CH,),NCH,(4,6-Me
(iVCH
,) Verlug.~gesellschuf/mhH, D-6Y4.51 Wc.mheiiiz, /YY4
c
2 6 40)l-
0570-0833!94:1818-/7Y4 S /0.00+ . 2 j d
A n g e w (%em. In/. Ed. Engi. 1994, 3 3 ~N o . 18
“A textbook example for stereoselective synthesis”-that is how one of the
referees described the title reaction.
With only 0.2 equivalents of a chiral
proton donor, prochiral enolates such
as 1 are protonated to give 2.
*
C. Fehr,* J. Galindo .............. 1888-1889
/
( 3 - 2 (94% ee)
1
Catalytic Enantioselective Protonation of
Enolates
*Author to whom correypondence should he addresyed
BOOKS
Houben-Weyl. Methoden der Organischen Chemie. Band E15, Teile 1-3. En-X- und
In-X-Verbindungen . H. Kropf. E. Schaumann
N . Krause .........................................
1891
Asymmetric Synthesis of Natural Products . A. Koskinen
K. Krohn ..........................................
1891
Organic Chemistry Using Clays M. Balogh, P. Laszlo
Zeolite, Clay and Heteropoly Acid in Organic Reactions . Y. Izumi, K. Urabe,
M. Onaka
G. Pandey ........................................
1892
Comprehensive Handbook on Hydrosilylation . B. Marciniec
M . Fink ...........................................
1893
Iron-Carbene Complexes . W. Petz
G. Rofh ............................................
1894
Author Index A-107
Angew.
C I i ~ v ~ lii .l t .
Ed Engl. 1994, 33. No. 18
Preview A-108
(0VCH
Verlugsgesellschuft mhH. 0-69451 Weinheim,1994
0570-0833/94/1818-179S$ 1O.OO-t .25:0
1795
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