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Metal-Induced Carbonylation of a Phosphane-Stabilized УCarbyne LigandФ Conversion of a Phosphorus Ylide-Carbonylmetal Adduct into an 1-Ketenyl Complex.

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C H i 3 C O 0 C 2 H5
5> N a O - C H = C H J 3 C 0 O C 2 H 5
bon monoxide a component of an enolate groupc2].We
have now investigated whether carbonyl ligand and ylidic
system can be also connected, when the latter is generated
directly at the metal center.
The cationic ylide complex 3, obtainable from the iron
iodide 1 and the silylated phosphorus ylide 2, provides a
suitable precursor for the synthesis of a model substance,
since silyl substituents usually favor the formation of carbanionic centers.
+ NaOMe
121 a) B. Kirste, W. Harrer, H. Kurreck, Angew. Chem. 93 (1981) 912; Angew.
Chem. Inr. Ed. Engl 20 (1981) 873. b) B. Kirste, H. van Willigen, H. Kurreck, K. Mobius, M. Plato, R. Biehl, J . Am. Chem. Soc. 100 (1978) 7505,
and references cited therein.- 'H-ENDOR experiments could recently
also be carried out on dicarbene-like systems in the quintet state (single
crystals of partially polymerized diacetylene); W. Hartl, Thesis, Universitat Bayreuth 1981.
[3] B. Kirste, H. Kurreck, W. Lubitz, K. Schubert, J. Am. Chem. Soc. 100
(1978) 2292; B. Kirste, H. Kurreck, K. Schubert, Tetrahedron Lett. 1978,
Metal-Induced Carbonylation of a PhosphaneStabilized "Carbyne Ligand" : Conversion of a
Phosphorus Ylide-Carbonylmetal Adduct into an
9'-Ketenyl Complex"]
By Siegfried Voran and Wolfgang Malisch*
Trialkyl(a1kylidene)phosphoranes react with metal-coordinated carbon monoxide v@ additioneat the carbon and
transylidationL2'. For the R3P-CH=C(O)- moiety formed
by this process at the metal a strong n-interaction between
ylide- and acyl-carbon has been proved, making the car-
- NaI, MeOH
The plausible rearrangement 4 + 5 + 6 represents a
novel type of reaction for metal-ylide~[~",
The attempt to perform an Me,Si/H exchange on 6 with
HCI (or HOSO,CF,) leads to degradation of the metal-ketenyl arrangement with formation of 7, Me3SiC1 and ketene, which polymerizes under the reaction conditions.
6 can be converted photochemically in the presence of
trimethylphosphane into 8, which like 6 , shows, neither in
boiling benzene nor in acetonitrile, q'-coordination with Iigand elimination which is characteristic for ketenyl complexes of molybdenum and tungsten'5b1.
,,:+p$- -~ ~ ~ p . 4
Angew. Chem. Int. Ed. Engl. 22 (1983) No. 2
Me3BX, - H2C20
lnstitut fur Anorganische Chemie der Universitat
Am Hubland, D-8700 Wiirzburg (Germany)
Received: September 22, 1982 [Z 155 IE]
revised: November 22, 1982
German version: Angew. Chem. 95 (1982) 149
The complete manuscript of this communication appears in:
Angew. Chem. Suppl. 1983, 128-139
s. Voran
Although 3 is inert towards transylidation with 2 or
Me3P=CHZit can be smoothly deprotonated with sodium
methoxide. However, instead of the corresponding neutral
complex 4, its isomer 6 is obtained, containing an 9'bonded ketenyl-ligand, which formally derives from the insertion of the carbyne C(SiMe3) into an Fe-CO bond. 6
forms deep-red crystals (m.p. 65 "C), is very readily soluble in pentane and cyclohexane, and is briefly stable towards air [IR(pentane): vCOketene
2025 (s), vC0 1938 (s)
cm '1.
markedly better resolution and the possibility of selecting
the desired species in a mixture by suitable positioning of
the external magnetic field, the ENDOR experiment shows
unequioocalty that both the 'H- as well as the I3C-ENDOR
signals have to be assigned to diradicals in the triplet state
or to triradicals in the quartet state. For the quartet state
(S=3/2), IJI%lal, a&= -9.4 MHz and aZm=+1.2 MHz
holds in the case of small dipolar coupling ( D = 22 MHz).
[*] Prof. Dr. W. Malisch,
2 Me,P=CHSiMe3
MeSP, - CO
0 Verlag Chemie GmbH, 6940 Weinheim, 1983
0570-0833/83/0202-015l $ 02.50/0
The intramolecular carbonylation of a carbyne-metal
fragment outlined in Scheme (2) is in our opinion of significance in connection with the homogeneously and heterogeneously catalyzed reduction of CO with H217a*b1,
though there is so far evidence in only one case for the existence of M=CR units as primary essential species for the
carbon-carbon coupling in the Fischer-Tropsch synthes~s"'~.The ketenyl derivatives synthesized from such species by CO addition possibly occur, inter a h , as intermediates during formation of oxygen-containing organic
compounds. Moreover, reaction (2) shows that the CR part
of a metal-bonded ylide moiety R,P=C- is synthetically
available and behaves like a carbyne ligandfS1.
HsC-CH 0
Received: September 28, 1982 [Z 159 IE]
revised: November 8, 1982
German version: Angew. Chem. 95 (1983) 151
The complete manuscript of this communication appears in:
Angew Chem. Suppl. 1982, 114-119
[I] Reaction of metal-coordinated carbon monoxide with ylides, Part 9. This
work was supported by the Deutsche Forschungsgemeinschaft, the Fonds
der Chemischen Industrie, and Hoechst AG, Werk Knapsack.-Part 8:
H. Blau, W. Malisch, J. Organomer. Chem. 235 (1982) C 1.
[2] H. Blau, W. Malisch, Angew. Chem. 92 (1980) 1063; Angew. Chem. Int.
Ed. Engl. 19 (1980) 1020; H. Blau, W. Malisch, S. Voran, K. Blank, C.
Kniger, J. Organomer. Chem. 202 (1980) C33; S . Voran, H. Blau, W. Malisch, U. Schubert, ibid. 232 (1982) C 3 3 ; W . Malisch, H. Blau, U. Schubert, Chem. Ber.. in press.
[S] a) F. R. Kreissl, D. Stiickler, E. W. Meineke, Chem. Ber. 110 (1977) 3040;
b) F. R. Kreissl, K. Eberl, W. Uedelhoven, Chem. Ber I10 (1977) 3782;
112 (1979) 3376.
[7] a) C. K. Rofer.De Poorter, Chem. Reu. 81 (1981) 447; b) W. A. Herrmann,
Angew. Chem. 94 (1982) 118; Angew. Chem. Int. Ed. Engl. 21 (1982) 117;
c) R. W. Joyner, J . Carol. SO (1977) 176.
[8] M. R. Churchill, H. I. Wasserman, S. J. Holmes, R. R. Schrock, Organometallics I (1982) 766.
B oc'
d OOC H3
4 : Y = C OOH
5 : Y = C O-CH2-COOCHzPh
Total Synthesis of Mucronin B**
By Ulrich Schmidt* and Ute Schanbacher
Over the last twenty years approximately 80 peptide alkaloids have been isolated and
They complex
alkaline metal ions and function as ionophores in plants.
In the majority of cases they.are active against gram-positive bacteria and fungi. Some inhibit the transfer of energy
in chloroplasts.
Recently we reported the first total synthesis of a 13membered peptide alkaloid-of ziziphin A 1""' - and we
now describe the first total synthesis of a peptide alkaloid-of mucronin B 2af3]-having a 15-membered ring
system. As characteristic structural unit it contains a benzene ring with a 12-membered "handle" over the m-position. In contrast to the 12- and 13-membered peptide alkaloids, which iLTe derived biogenetically from tyrosine and
contain a 0-phenoxy amino acid in the ring, in the 15membered compounds the handle is not linked to the benzene ring via a phenol ether function but via a C-C bond.
The biogenesis of these compounds presumably starts
from a m-phenylenedialanine.
Prof. Dr. U. Schmidt, U. Schanbacher
Institut fur Organische Chemie der Universitat
Pfaffenwaldring 55, D-7000 Stuttgart 80 (Germany)
Synthesis of Peptide Alkaloids, Part 8; Amino Acids and Peptides, Part
40. This work was supported by the Fonds der Chemischen Industrie,
BASF AG, and the Deutsche Forschungsgemeinschaft. Dr. W. Rozdzinski is thanked for numerous mass spectra and Prof. Dr. K:D. Jany
for the determinations of do-isoleucine. Degussa AG is thanked for a
generous gift of amino acids and noble metal catalysts.-Part 7: Liebigs
Ann. Chem.. in press; Part 39: Angew. Chem., in press.
0 Verlag Chemie GmbH. 6940 Weinheim, 1983
4, 2a +
* 9 : 65%
: 50%
0: RSS
I l a + 110
1 l a + 110 : 60%
~ L Y
+ 20 : 40%
a: CH,I, K2C03. DMF, RT, 3 d ; b: H2/Pd, CH30H, RT, 3 bar, 5 h; c:
O(COOtBu)2,Dioxane/H20, NaHCO,, 10 h; d: Carbonyldiimidazole, THF,
RT, 0.5 h; e: Mg(00C-CH2-COOCH2Ph)2, THF, S O T , 5 h; f NaN02,
CH3COOH/H20 (2:1), O T , 2 h; g: H2/Pd, CH,COOH, RT, 9 h ; h:
C1COOCH2Ph, Dioxane/H20, NaHCO,, O T , 10 h; i: NaOH, H20/Dioxane, RT, 4 h; k: Dicyclohexylcarbodiimide(DCCD), (S.S)-H-lle-Phe-OCH,,
CH2C12,0 "C, I0 h ; 1: NaOH, HzO/Dioxane, RT, 4 h; m: DCCD, C,F,OH,
CH2CI2,O"C, I0 h; n: H2/Pd, Dioxane, 95 "C, 5 h; 0 : Ac20, Pyridine, RT, 20
h ; p: 10 CF,COOH, 1.2 PhSeH, 5 0 T , 20 h ; q: 3 NaI04, THF/CH30H/H20
(1 :2: I), RT, 0.5 h.-Z=PhCH2OCO, Boc=~BuOCO.
The dehydroamino acid 3 serves as starting material for
the synthesis of mucronin12b1.After N-methylation, hydrogenation, and introduction of the Boc group to afford 4,
the carboxy group was transformed into the aminoethanol
size chain (4 ---t 5 + 6). Hydrolysis of 6 to give the amino
acid and coupling with Ile-Phe-OCH3 led to the tripeptide
7,which was converted into the pentafluorophenyl ester 9 ,
the educt for the ring closure. Cyclization proceeded by
"catalytic hydrogenation under high-dilution conditions"[zcl. The high yields (85%) of ring compounds 10a
and lOflf4] provide further evidence for the superiority
of this ring-closure method, compared to conventional
methods, for the synthesis of 12- to 15-membered cyclopep-
0570-0833/83/0202-0152 S 02.50/0
Angew. Chem. Inr. Ed. Engl. 22 (1983) No. 2
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adduct, уcarbyne, ketenyl, complex, stabilizer, induced, ligand, carbonylation, carbonylmetal, metali, phosphane, ylide, conversion, phosphorus
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