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Dispiro[2.0 (3).2

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lead to formation of difficultly separable mixtures. We
have now developed a method for synthesizing the silanes
Ph,Si(H)X (5), in the first instance, in good yields and free
of silicon-containing by-products.
Triorganosilanes R3SiH react photochemically with
c ~ M n ( C 0 ) ~ (Cp=q'-C,H,)
($CH3C5H4)Mn(C0)3( I ) to give Cp(CO),(H)Mn-SiR,
the (q5-CH3C5H4)-complex,respectively"'. We found in
the case of diphenylsilane (2) (and other diorganosilanes)
that only one Si-H bond is cleaved:
hu. - CO
(MeCp)Mn(CO)S + Ph,SiH,
i 2)
( 3 ) ------+
(01, X = F; (h), X = C1;
(MeCp) = q5-CH3C5H,
X = Br; (d), X = I
In complex (3)IZ1,which is obtained in 75% yield, the remaining H-atom can be replaced by a halogen atom without the Mn-H or the Si-H bond being opened. Thus,
(4a) can be prepared in 78% yield by reacting (3) for 30
min with a stoichiometric amount of [Ph3C]BF4in CH2Clz
at room temperature. When a solution of (3) in CCI, is
treated with a small amount of PCI,, (3) is chlorinated to
(4b) in 72% yield within a few minutes. When dilute solutions of stoichiometric amounts of Br, or I, are slowly added dropwise at 0 ° C to dilute solutions of (3) in pentane,
(4c) and (4d) are obtained in 70 and 69% yield, respectivelyThe new complexes (3) and (4a)-(4d) can be isolated as
pale yellow solids by crystallization from pentane or by
They cannot be kept in the analytically pure state over a longer period, even with cooling.
Their stability falls off on going from (3)=(4a) to (4d) and
rapidly decreases in polar solvents.
Reaction of (4) with CO under pressure leads to formation of the silanes (5) without by-products and with cleavage of the protecting group and regeneration of ( I ) . Beginning thermal decomposition of (4) is no problem, since the
same silanes (5) are formed.
5 0 6 0 bar CO
(MeCp)Mn(CO), + Ph,Si(H)X
pentane,100-120T, 3 h
f 1)
The silanes (S) can be smoothly separated on a gram
scale from complex ( I ) , i. e. without major losses, by preparative high pressure liquid chromatography (PHPLC)'"
(overall yields of (5) 80-90% depending on the educt).
The reactions described here thus enable one only of the
two silicon-bonded hydrogen atoms of diphenylsilane (2)
to be replaced by halogen.
Received: November 26, 1980 [Z 817 IE]
German version: Angew. Chem. 93. 683 (1981)
CAS Registry numbers:
(I), 12108-13-3; (2). 775-12-2; (3). 78420-94-7; ( 4 ~ )78420-95-8;
(4b), 7842096-9; (4c). 78420-97-0; (4d). 78420-98-1 : (So). 1013-91-8; (Sb). 1631-83-0; (Sc).
17995-01-6; (Sd), 78408-01-2.
111 A . J . Hurt-Dauis. W. A . G. Graham, J. Am. Chem. SOC.94,4388(1971); E.
Colorner, R. J. P. Corriu. A. yioOx. lnorg. Chem. 18, 695 (1979).
3 2 v~.+-~=l9Ol
[2] IR (pentane): vco= 1994 (vs), 1935 (vs), ~ ~ , - ~ = 2 0 (w),
(w) cm-'; 'H-NMR (CCI,, TMS int.): 6=8.0,7.4 (m, 10H, C,H,), 6.7 (d,
1 H, Si-H), 3.95 (s, 4H, CJH& 1.5 (s, 3 H, CH3), - 11.5 (d, 1 H, Mn-H);
J H M n s I H =4.95 Hz.
0 Verlag Chernie GmbH. 6940 Wernherrn. 1981
[3] All the compounds gave correct elemental analyses. The IR and NMR
spectra essentially correspond to those of ( I ) 121.
[4] Separator system: Knauer steel column (50x 1.6 cm) packed with Nucleosil 100-30 silica gel [for (Sa)] and with Alox 60-D 10 aluminum oxide
[for (5b-c)]. Pump and detector were units from the Philips-Pye-Unicam
LC system. Pump rate 25 mL/mn, detector wavelength 254 nm. Eluent:
heptane/ether (5 :I).
Dispiro[]deca-7,9-diene as a Ligand in
Carbonyl-Transition Metal Complexes'*']
By Dieter Wormsbacher, Frank Edelmann,
Dieter Kaufmann, Ulrich Behrens, and Armin de Meijere[*'
Dedicated to Professor Edgar Heilbronner on the occasion
of his 60th birthday
The highest occupied molecular orbital (HOMO) of dispiro[]deca-7,9-diene( I ) [formula numbered by analogy to (211 is exceptionally high""] owing to conjugation of
the diene moiety with the two neighboring spirocyclopropyl groups""]. As is well known, cyclopropyl substituents
are particularly effective electron donors towards electrondeficient centers, but poor electron acceptors"b1. Since a
diene(tricarbony1)iron group as a rule also acts as an electron donor'21,we were interested to know whether or not
there was a mutual electronic influence between diene(carbony1)metal unit and spirobicyclopropyl group.
(do), M
(4h), M
= Fe,
= Fe,
( 4 c ) , M = Fe,
(4dj, M = Ru,
L = CO
L = P(C,H,),
L = P(OC,H5)3
L = CO
(So), M
= Fe,
L = co
(Sh), M = Fe,
L = P(C&d,
The tricarbonyliron complex (4a) is obtained as an
orange-yellow oil in 75% yield by reaction of ( I ) with (benzy1ideneacetone)tricarbonyliron ((bda)Fe(C0)3)[3"1 followed by chromatography on silica gel. In an analogous
way reaction with (bda)[P(C6H5)3]Fe(CO)>3b1and
afforded the corresponding
complexes (4b) (40%, yellow crystals, m.p. 198- 199°C)
and (4c) (35%, orange oil), respectively. Surprizingly, the
reaction of (I) with Fe2(C0)9led to formation of (4a) as the
only product, although many vinylcyclopropane derivatives undergo ring opening under these conditions141.
R u ~ ( C O )catalyzes
the rearrangement of ( I ) to o-ethylstyrene""', whereas reaction with the more reactive tricarbonyl( 1 ,5-~yclooctadiene)ruthenium~~"~
leads, under mild
conditions, to the complex (4d) (21%, lemon-yellow oil). In
D. Wormsbacher, Dipl.-Chem.
F. Edelmann, Dr. D. Kaufmann, Dr. U. Behrens
Fachbereich Chemie der Universitat
Martin-Luther-King-Platz 6, D-2000 Hamburg 13 (Germany)
This work was supported by the Deutsche Forschungsgemeinschaft and
the Fonds der Chemischen Industrie.
[*] Prof. Dr. A. de Meijere, Dipl.-Chem.
0570-0833/81/0808-0696 $02 50/0
Angew. Chern Int Ed Engl. 20 (1981) No.
contrast, ( 1 ) cannot be converted-even by treatment with
a tricarbonylchromium complex, in which the spirobicyclopropyl
group also ought to function as a ligand['].
Reaction of 5,5,6,6-tetramethyl-1,3-cyclohexadiene(3)16],
having the same type of substitution as ( I ) , with
(bda)Fe(CO), similarly afforded the tricarbonyliron complex [(6)].The spectroscopic data of (6) and those of the
complexes (5aj1'' and (5b)I8]of 1,3-cyclohexadiene (2) have
been selected for comparison with those of the new carbonylmetal complexes (4a)-(4d) (Table 1).
Table I . Spectroscopic data of the carbonylmetal complexes (4)-(7) and the
free ligands (1)-(3j [numbering as shown in ( i j and (2)l.
SolCharacteristic data
vent [a] vC=O [cm '1 or GTMS(assignment)
I R spectrum
200 1
' H - N M R spectrum [b]
4.67 (H2.'),
2.23 (HI4),
0.21, 0.15 (H'.Xy"')
0.47, 0.36, 0.16, 0.03
0. I9 -0.03
0.31, 0.19 (H7x.9.'")
1.41, 1.14 (H'")
I .96
0.91, 0.71
0.9 1
7.41 (t, H2), 6.01 (t. H'), 5.51 (d, HI), 3.95 (d, H4), 1.93 (m,
H"), 1.63 (dt, H'), 1.18 (m, H'), 0.99 (t. H'"), 0.73 (dt, H'),
0.61 (dt, H')
"C-NMR spectrum [b]
212.6 (C=O),
83.8 (C'.'),
72.9 (C ' "),
24.5 (C'.'),
15.4 (C7y'n.i0), 12.6 (Cx~""7v
133.7 (C'.'), 123.6 (C'-"), 20.8 (C'-"), 11.6 (C7h.9.'11)
138.8 (C2.'),121.0 (C'."), 37.3 (C'.'), 22.3 (C7n.9.10)
200.8 ( C d ) , 110.5 (C'), 100.1 (C'), 95.7 (C'), 85.1 (C"),
72.7 (C'), 25.6 (C5),24.6 (C'), 24.4 (C"'), 13.1 (C'), 10.7
[a] 1 cyclohexane, 11 KBr, 111 C,D,, IV CCI,, V CD2C12.[b] Detailed analysis
of the ' H - and "C-NMR spectra of (4a) and (6): H. Giinther. unpublished results. [cJF. M . Choudhnrc. P. L. Pauson. J. Organornet. Chem. 5. 73 (1966). [d]
R . Burton. L . Pratt. G . Wilkinson. J. Chem. SOC.1961. 594.
From the C=O stretching vibration frequencies of (4a),
which were found to be insignificantly lower than those of
(5a), it can only be concluded that there must be very little
difference between the n*-MOs of (4a) and (5a)[']. The 'Hand I3C-NMR data would also lead to the same conclusion. Thus, the signals of the cyclopropyl protons of (4a)(4d) are shifted only slightly (0.1-0.2 ppm) upfield compared to those of ( I ) . and the I3C-NMR signals of the cyclopropyl C-atoms C7-C10 in the complex (4a) are even
shifted downfield. Consequently, the metal-complexed
diene moiety cannot exercise its electron-donor action on
the spirobicyclopropyl group.
According to an X-ray structure analysis the diene
moiety in (46) is completely planar (see Fig. I), as is usual
in such complexes['I. The angle between this plane and the
plane is ca. 39"; the bicyclopropyl
group, with a dihedral angle of ca. 4", has an almost synplanar conformation.
Ed Engl 20 (1981) N o X
Fig. I . Structure of (46) in the crystal (monoclinic crystals, space group P2,/c,
a=871(1), b = 1542(1), c = 1867(2) pm,@=97.3(1); 2478 measured reflections,
refined to R=0.041).
The most remarkable property of (4a) is its smooth reaction with ethereal tetrafluoroboric acid at room temperature to give the stable complex ( 7 4 while the free ligand
(I) spontaneously polymerizes with superacids, even at
- 80 OCI'l. The orange-yellow crystalline compound (7b).
which precipitates from the aqueous solution of oily [7a)
on addition of ammonium hexafluorophosphate, is to our
knowledge the first complex of an ethylenebenzenium ion
[formula numbered by analogy to (211. From its ' H - and
I3C-NMR data (see Table I ) it is evident that the positive
charge-other than in the case of the uncomplexed
ion"O1-is not delocalized into the cyclopropyl group. Consequently, (7) should react with nucleophiles like a tricarbonylcyclohexadienyliron cation["] and not like an ethylenebenzenium ion.
Received: December 12, 1980 [Z 809 IE]
German version: Angew. Chem. 93, 701 (1981)
[ I ] a) A. d e Meijere, Chem. Ber. 107. 1684 (1974): b) cf. recent review: Angew. Chem. 91, 867 (1979); Angew. Chem. Int. Ed. Engl. 18. 809 (1979),
and references cited therein.
12) Cf. reviews in: R . Pettit, G. F. Emerson. Adv. Organomet. Chem. I . I
I31 a) J . A. S. Howell. 8.F. G. Johnson, P. L. Josty. J. Lewis. J. Organornet.
Chem. 39. 329 (1972): b) B. F. G. Johnson, J. Lewis. C . R . Stephenson. E.
J. S. Vichi. J. Chem. SOC.Dalton Trans. 1978. 369; c) A. J. Deeming. S .
S . Ullah. A . J. P. Domingos, B. F. G. Johnson, J. Lewis, ibid. 1974.
141 Cf. a) R . Aumonn, H . Ring, Angew. Chem. 89. 47 (1977): Angew. Chem.
Int. Ed. Engl. 16. 50 (1977); b) S . SareI. Acc. Chem. Res. 11. 204 (1978);
C) P. Eilbrarht, U. Mayser. Chem. Ber. 113. 221 1 (1980). and references
cited therein.
151 Cf. on the other hand: W . E. Bleck. W. Grimme. H. Gunrher. E. Vogel,
Angew. Chem. 82. 292 (1970); Angew. Chern. Int. Ed. Engl. 9. 303
0 Verlag Chemre GmbH. 6940 Wernherm. 1981
0570-0833/81/0808-0697 $02 50/0
[6] D . Kaufmann. A. d e Meijere. Tetrahedron Lett. 1979, 779.
171 R . Burton, L. Pratt. G. Wilkinson. J. Chem. SOC. 1961. 594.
[8] F. M . Chaudhari. P. L. Pauson. J. Organomet. Chem. 5. 73 (1973).
[9] A. d e Meijere, Chem. Ber. 107, 1702 (1974).
[lo] G. A . Oloh. R . D. Porter. J. Am. Chem. SOC.92. 7627 (1970).
[I I ] Cf. A J Birch, I . D. Alpers in H. Alper: Transition Metal Organometal.
lics in Organic Synthesis, Academic Press, New York 1976, p. 1-82.
Class I
Direct and Inverse Reactivity-Selectivity
Relationship in the 11.21-Addition of Singlet
Carbenes to Olefins[*']
By Wolfgang W. Schoeller"]
Dedicated to Professor Josef Goubeau on the occasion
of his 80th birthday
Hitherto it has generally been assumed that the reactivities of carbenes towards olefins decrease with increasing
selectivity in the order CF, > CC12> CBr,"]. Contrary to
this common understanding, we show that the selectivity
of singlet carbenes CL2 (L=halogen, OCH3 etc.) can increase with increasing reactivity (inverse reactivity-selectivity relationshipi2').
According to frontier orbital theory'31 the interaction
between a carbene (C) and an olefin (0)(Scheme 1) is
given by the following relation:
where E is determined in this picture by mutual transfer of
electron density between the frontier orbitals HOMO and
LUMO and is proportional to the logarithm of the rate
constant of the reaction. A variation in 0 (0,,02,
causes a change in reactivity (Igk,, lgk2,. ..lgk,) and hence
corresponds to a change in the interaction energy E . If the
trapping olefins 0, differ only slightly in their electronic
properties (e.g . by alkyl substitution at the x-system), the
frontier orbitals of 0, will be energetically raised or loweredI4] by the small amount A[51.Hence selectivity [eq. (b)]
is related to reactivity [eq. (a)] as derived in the formalism
of differential frontier orbital theory.
s = aE -
[(E&+A)- Eqpcl*
For a reactivity-selectivity relationship the following
limiting cases ( S > 0) can be recognized:
Priv.-Doz. Dr. W. W. Schoeller
Fakultat fur Chemie der Universitat
Postfach 8640, D-4800 Bielefeld (Germany)
This work was supported by the Fonds der Chemischen lndustrie and
the Deutsche Forschungsgemeinschaft.
Class I : Increase in selectivity and decrease in reactivity
on raising the LUMO energy level of the carbene. This
case corresponds to the classical reactivity selection principle (RSP)'" (direct RSP). In the series of the halocarbenes
( L = F , CI, Br) the energy difference between the innermolecular frontier orbitals ( X = ELUMOfC)
- EHOM,,,,) decreases (less favorable C,,. L,, overlap, n=2, 3, 4 ) e.g.,
with respect to CF, the species CCl, is more reactive, both
electrophilically as well as nucleophilicalIyr61.
Hence, the reactivity according to eq. (a) increases and
simultaneously the selectivity according to eq. (b) decreases. Similar considerations hold for the selectivity region S<O (nucleophilic carbenes).
For the series of halocarbenes we have plotted their selectivities against the corresponding LUMO energies"]
(Fig. I).
0 Verlag Chemie GmbH, 6940 Weinheim. 1981
Scheme 2.
Fig. I . Relative selectivities (with respect to CCI2 under standard conditions
[I)) rn of the halocarbenes as a function of their LUMO energies (in /?).
Accordingly, the selectivity of the carbene increases with
increasing LUMO energy. Therefore, the halocarbenes are
ruled by the direct RSP, which is in agreement with the
view"] that the selectivity of carbenes increases with increasing resonance stabilization (CBr,<CCI,<CF,).
Class 11: Decrease in reactivity and concomitant decrease in selectivity (inverse RSP) with increasing LUMO
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Angen: Chem I n / Ed. Engl 20 ( I Y X I ) N o X
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