close

Вход

Забыли?

вход по аккаунту

?

Iron Carbonyl Complexes of the Dimers of Cyclooctatetraene and Bullvalene.

код для вставкиСкачать
be explained by the difference in direction of their polarizations (HS'GeS-Cl3 and Hs-Sis'C13 [4]).
Received, April 20th, 1964
[ Z 727/554 IE]
German version: Angew. Chem. 76, 498 (1964)
[I]0.M . Nefedov and S . P . Kolesnikov, Izv. Akad. Nauk SSSR,
Otdcl Khim. Nauk 1963,2068; 0. M . Nefedov, S . P . Kolesnikov,
A . S . Charliatirrov, and A . D . Petrov, Dokl. Akad. Nauk SSSR
1-54, 1389 (1964).
[2]0.Dirnroth et al., Ber. dtsch. chem. Ges. 40,2376 (1907); 43,
2757 (1910);50, 1534 (1917).
[3] M . E. V o / p h et al., Tetrahedron 18, 107 (1962); lzv. Akad.
Nauk SSSR, Otdel Khim. Nauk 1963, 2067.
[4] C. Enborn: Organosilicon Compounds. Butterworths, London 1960.
Compounds Containing the Si -N -B Linkage [l]
By C. R. Russ and Prof. Dr. A. G. MacDiarmid
John Harrison Laboratory of Chemistry
and Laboratory for Research o n the Structure of Matter
Philadelphia, Penn. (U.S.A.)
Geymayer, Rochow, and Wannagat [2] recently prepared the
compounds [(R3Si)zN]2BF ( I ) , (R3SiNBCI)3 (2), and
[R3SiNBN(SiR3)2]2 (3), where R = CH3. We have also obtained (I) and (3) by somewhat different synthetic methods,
and have prepared [(CH3)3Si]zNBF2 ( 4 ) by two different
types of reaction.
BF3 was passed through a solution of [(CH&Si12NLi [ 3 ] in
pentane/hexane; subsequent distillation at reduced pressure
afforded good yields of ( I ) , m.p. 18 "C, b.p. 63 "C/0.5 mm. Its
structure was confirmed by elementary analysis, infrared and
IH-NMR spectra (dioxane as internal standard; 8 = 0.21 ppm
relative to low field of tetramethylsilane); mol. wt. found 350,
calc. 348. The reverse order of mixing of the reactants did
not result in the formation of (4), even at -78 "C. However,
when ( I ) was heated with BF3 at 95°C for several hours,
good yields of ( 4 ) , m.p. -31.6'C, b.p. 21 OC15.2 mm, were
obtained. Compound (4) is a colorless liquid. Its structure
was confirmed by elementary analysis, and infrared and
mass spectra.
Solutions of [(CH3)3Si]3N [4] in pentane d o not react with
BF3 at room temperature. However, on heating the reactants
in t h e absence of solvent at 130OC for several hours, large
amounts of (4) were obtained.
When (4) was heated in a sealed tube at 2COoC for several
hours, no BF3 was evolved. This indicates that reaction (a)
is not reversible. Instead, (CH-,)3SiF was eliminated from (4),
and it appears that the B-fluoroborazine analogous to (2)
was produced.
When ( I ) was heated at 200°C for 36 h in a sealed tube,
(CH3)3SiF was eliminated, and ca. 75 7; of (3) were obtained.
13)
Si(CH,),
Angew. Chem. internat. Edit.
VoZ. 3 (1964) 1 No. 7
The structure of(3),m.p. 208 "C, was confirmed by elementary
analysis, and infrared and IH-NMR spectra (dioxane as
internal standard: 8[(CH3)3Si]zN = 0.19 ppm and
F(CH3)JSiN = 0.15 ppm relative to low field of TMS); mot.
wt. found 520, 511, calc. 517. The N M R signals were in the
ratio I .96: 1. The N M R data indicate that the nitrogen atoms
o f the ring system are less effective in withdrawing electrons
from the protons than the exocyclic nitrogen atoms. This
suggests that delocalization of the lone pairs of electrons o n
the nitrogens in the ring is not extensive. A similar conclusion,
based o n different experimental evidence, has been reached
regarding electron delocalization in the ring system of
[ ~ - C ~ H ~ ( H ) N B N ( ~ - C ~the
H ~only
) ] Z other dimeric borazine
derivative known [5].
Received, April 24th, 1964
[Z 731/557 IEl
German version: Anyew. Chem. 76, 500 (1964)
[l] This work was supported by the Advanced Research Projects
Agency, Office of the U.S. Secretary of Defense.
[2]P . Geyrnn-ver,E. G. Rochow, and U. Wannagat, Angew. Chern.
76,499(1964);Angew. Chem. internat.Edit.3, (1964),in the press.
[3] U. Wonnogot and H . Niederpriirn, Angew. Chem. 71, 574
(1959).
[4] V. J . Goubenu and J. JifnPnez-Bnrberd, Z. anorg. allg. Chern.
303, 217 (1960).
[ 5 ] M. F. Loppert and M . K . Majurrldar, Proc. chem. SOC.(London) 1963, 88.
Iron Carbonyl Complexes of the Dimers of
Cyclooctatetraene and Bullvalene
By Priv.-Doz. Dr. G. N. Schrauzer and
Dipl.-Chem. P. Glockner
Institut fur Anorganische Chemie
der Universitat Munchen (Germany)
and by Dipl.-Ing. R. Mer6nyi
Union Carbide European Research Associates,
Brussels (Belgium)
Light-induced addition of cyclooctatetraene onto cyclooctatetraeneiron tricarbonyl [I] leads to two isomeric
complexes, viz. C16H16Fe(C0)3 ( I ) , m. p. 118 " c , and
ClhH16Fe(CO)3 (2), m.p. 172 "C (decomp.).
Compound ( I ) is also formed directly by the reaction of
Fez(C0)g with the dimer of cyclooctatetraene C16H16 (3),
m.p. 76°C [2]. ( I ) is a n-complex whose organic ligand
undergoes fast and reversible valence isomerization; its N MR
spectrum is strongly temperature-dependent. However, the
structure of (2) does not "fluctuate".
The reaction of (3) with Fe(C0)s at 160-17O'C gives
isomer ( 4 ) , m. p.
besides ( I ) , another C&16Fe(CO)3
175-180 "C (decomp.), a binuclear complex C I ~ H I ~ F ~ ~ ( C O ) ~
(5), m.p. 191 ' C , and a trinuclear complex C I ~ H I ~ F ~ ~ ( C O ) ~
( 6 ) , m.p. 170'C (decomp.) [3].
Complex ( 5 ) is also formed by the reaction of ( I ) with
Fe(C0)s at I80 "C, as well as by heating (6) in a sealed glass
tube to 180'C. The complicated N M R spectra of ( 4 ) . (5),
and ( 6 ) are not temperature-dependent ; thus, the reversible
valence isomerization of the parent hydrocarbon is suppressed by complex formation. The structures of ( 4 ) and (6)
are still unknown [4].The proposed structure for ( 5 ) is not
in contradiction to its N M R spectrum.
(bullThe reaction of tricyclo[3,3,2,04,6]deca-2,7,9-triene
valene) (7) [2,5] with FeZ(C0)g in boiling benzene affords
the complex CloHloFe2(C0)6 (S), m.p. 120°C; when heated
to 140 "C in the presence of excess triphenylphosphine, (8)
decomposes into bullvalene (7) and Fe(CO)3.2P(C6H5)3 ; at
180°C in a n autoclave, it is transformed into the known
complex 9,IO-dihydronaphthalenediiron hexacarbonyl (9),
m.p. 195 197 'C (decomp.) [6]. The N M R spectra of ( 8 )
509
and (9) support the proposed structures; unlike t o that of
bullvalene (7), they are not temperature-dependent. Thus,
it is possible to stabilize the intermediates of the transformation of bullvalene into naphthalene [2] as (8) and (9)
by complex formation, although these intermediates were
The olefinic region in the NMR spectrum is similar to that of
1,6-dimethylcycloheptatriene[4]. In the infrared spectrum a
band at 1660 cm-1 (C=C), typical of enolic ethers, appears.
The yellow color of (4) is due t o the long-wave end of a broad
ultraviolet absorption band with Amax = 297 m p (log E =
(7)
(9)
not isolated in their non-complexed form. This transformation
is favored by the presence of the Fe(CO)3 groups and takes
place at a much lower temperature than with free bullvalene;
bullvalene (7) therefore loses its "fluctuating" structure on x complex formation.
Received, April 27th, 1964
[Z 729/555 IEJ
3.25). On standing for some time with maleic anhydride, (4)
reacts t o form the adduct (5), m.p. 235 "C (decomp.), derived
from (3) [5].
German version: Angew. Chem. 76, 498 (1964)
~.
_.
[l J G. N. Schrauzer and S . Eichler, Angew. Chem. 74, 585 (1962);
Angew. Chem. internat. Edit. 1 , 454 (1962).
121 G. Schroder, Angew. Chem. 75, 722 (1963); Angew. Chem.
internat. Edit. 2, 481 (1963).
[3] Complex (6) is also formed on irradiation of ( I ) and (2) in
the presence of Fe(CO)5 and was originally considered as a
binuclear complex CloHloFez(C0)6. Recent osmometric molecular-weight determinations in C6H6 and CHCI, confirmed the
formula C16H16Fe3(C0)9.
[4] An X-ray study is in progress ( M . R . Truter et al., University
of Leeds, England).
[5] W . V . E. Duering and W. R. ROth, Angew. Chem. 75, 27
(1963); Angew. Chem. internat. Edit. 2, 115 (1963); Tetrahedron
19, 715 (1963).
[6] E. Weiss, W . Hiibel, and R . MerPnyi, Chem. Ber. 95, 1155
(1962).
The synthesis of (4)instigated reinvestigation of the dehydro[ l b, 1c].
bromination of 1,2-epoxy-4,5-dibromocyclohexane
Previously only phenol had been isolated from this reaction.
When 1,5-diazabicyclo[3,4,O]non-5-ene[6] is used as dehydrohalogenating agent, a yellow elimination product, b. p.
27 "C/14 mm, was obtained in good yield in 95 ?< purity; it is
assumed to be oxepin. The product began t o rearrange into
phenol above 70 "C, and its catalytic hydrogenation yielded
mainly oxepane. Maleic anhydride added onto it fairly rapidly, even at 20'C; the adduct melts at 264°C (decomp.).
Finally, the N M R spectrum shows absorptions only in the
olefinic range (three multiplets with relative intensities of
1 : 1 : 1, centered at 3,9 T, 4.4 T,and 4.7 T) which suggest that
the product is actually oxepin [7].
Received, May 4th, 1964
[Z 7321561 IE]
German version: Angew. Chem. 76, 535 (1964)
~~
Synthesis of an Oxepin Derivative
By Prof. Dr. E. Vogel, Dip1.-Chem. R. Schubart, and
Dr. W. A. Boll
Institut fur Organische Chemie der Universitat Koln
(Germany)
Oxepins are of theoretical interest on account of their cyclic
8-x-electron system, and several attempts at their synthesis
have been made 111. 2,7-Dimethyloxepin (4) is the first simple
representative [2] of this class of compounds t o be prepared.
It is obtained in 6 0 % yield as a stable yellow liquid, b.p.
51 OC/14 mm, n'," = 1.5045, when the dibromo compound (2),
m.p. 85-86OC (derived from the unsaturated epoxide ( I )
131) is dehydrobrominated with potassium t-butoxide in ether
at 0 "C. The epoxide (3) is a likely intermediate.
[la] S. Olsen and R. Bredoch, Chem. Ber. 91, 1589 (1958);
[b] J . Ferry, Diploma Thesis, Technische Hochschule Karlsruhe,
1958; [c] J. Meinwald and H . Noraki, J. Amer. chem. SOC.80,
3132 (1958); [d] J . Meinwald, D. W. Dicker, and N . Danieli, ibid.
82, 4087 (1960); [el E. E. Schweizer and W. E. Parham, ibid. 52,
4085 (1960).
[2] 3-Benzoxepin and some of its derivatives were described by
K . Dimroth et al., Angew. Chem. 69, 95 (1957); Chem. Ber. 90,
1623 (1957); Angew. Chem. 73, 436 (1961); 1-Benzoxepin was
recently obtained in our laboratories (unpublished).
[3] W. Hiickel and U.Wt'rfel, Chem. Ber. 88, 338 (1955).
[4] Unpublished experiments with H . D. Ruth.
[5] The kinetic and thermodynamic relationship between oxepins
and the valence-bond isomeric aromatic oxides has still to be
investigated.
[6] E.Truscheit and K . Eiter, Liebigs Ann. Chem. 658, 65 (1962).
[7] Note added in proof (May 25th): Oxepin has now been
prepared in pure form, b.p. 38 T / 3 0 mm, n z = 1.5162, broad
ultraviolet absorption band with Amax = 271 mr* (log E = 3.15),
in cyclohexane. The compound appears to exist in equilibrium
with its valence tautomer benzene epoxide.
A New Synthesis of N-Alkylpyrroles
By Dr. R. Kreher and cand. chem. H. Pawelczyk
Institut fur Organische Chemie der Technischen Hochschule
Darmstadt (Germany)
The proof of the structure o f (4)is based mainly on its N M R
spectrum, which has a singlet at 8.1 T (6 methyl protons) and
two multiplets centered at 4.1 and 4.7 T (two protons each).
510
N-Alkylpyrroles (3) are formed in 50-60 7; yield by the
action of acetic anhydride at 0 OC [ l ] on N-alkyl-A3-pyrrolineN-oxides (2), which are in turn obtained in almost quantiAngew. Chem. internat. Edit.
Vol. 3 (1964) No. 7
Документ
Категория
Без категории
Просмотров
0
Размер файла
232 Кб
Теги
carbonyl, bullvalene, dimer, iron, cyclooctatetraene, complexes
1/--страниц
Пожаловаться на содержимое документа