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Novel Reactions of Phosphorus Ylides with Carbonyl(cyclopentadienyl)metal Complexes Preparative Access to -Alkylidene Complexes and Unexpected Acylations.

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Novel Reactions of Phosphorus Ylides with
Carbonyl(cyclopentadieny1)metal Complexes:
Preparative Access to p-Alkylidene Complexes
and Unexpected Acyiations[ *I
containing by-product, for which we have proposed the
structure 18,19-didehydrocobyrinic acid c-amide (3)I2I.
Such a compound is of interest in its metal-free, non-amidated form as the connecting link between metal-free and
cobalt-containing corrinoids in the biosynthesis of vitamin
Bl2I2].We have now unambiguously proved the structure of
the hexamethyl ester of (3) as dicyano-18,19-didehydrocobyrinic acid hexamethyl ester c-amide (4).
The absorption spectrum of (4) shows the typical a,o,ystructure of cobalt-containing corrinoids. The substantial
bathochromic shift of the main absorption bands
(369-396 nm, 545-590 nm, and 584-626 nm) compared
to those of the heptamethyl ester of dicyanocobyrinic acid
("cobester") indicates a lengthening of the corrin chromophore.
The presence of the same peripheral groups as in the
hexamethyl ester of (2) follows from the 'H-NMR spectrum, which contains the signals of the protons of one amide group and of six methoxy- and eight angular methyl
groups. An AB system (J=16.7 Hz) appears at 6=3.47/
3.38 which is assigned to the methylene group of a
By Richard Korswagen, Reinhold A h , Dieter Speth, and
Manfred L. Ziegler"'
Phosphorus ylides R3P=CR'R' prove to be astonishingly versatile in their reactions with metal complexes. Essentially three types of reaction have already been reported: 1) ligand exchange with formation of products in
which the ylide carbon atom functions as o-donor"]; 2) ligand exchange and transylidation whereby a hydrogen
atom attached to ylide carbon is replaced by an organometallic group[*]; 3) peripheral ligand reactions in which C O
groups of the complex participateI3].
We have now discovered two further different types of
reaction which take place between phosphorus ylides and
organometallic substrates.
On reaction of the iron complex (I) with ylides
PH3P=CHR (Scheme 1)
cis f ~ r )
[q5-CpFe(CO)z]s+ P h 3 P = C H
R
-
(2), R
= H;
trans (h)
( 3 ) . R = CH3;
(4), K
n-CSH7
=
A
THF, dioxane
H\ /H
cp\
/
R
CP,
PPh3
oc'
Fe=C,
oc'
c
il
/c\ /c'o
F'e-F
\$/
e
'Cp
Scheme 1.
CH2C02Memoiety adjacent to a double bond. The position of this double bond and that of the amide function
follows from the I3C-NMR spectrum, which was recorded
despite the small amount of substance available (ca. 2
mg=ca. 2 pmol, recording time 64 h for 351 000 accumulations). The deshielding of C-5,7, and 8 and of C-C by 3- 5
ppm in (4) (relative to "~obester'"~])and the shielding of
C-6 by ca. 2 ppm are consistent with a c-amide group. In
~obester'~]
the signals of C-18 and C-19 appear at 6=39.2
and 74.7, respectively; in(4) they are shifted into the olefinic
region, presumably to 6= 124.6 and 151.5, respectively.
The signals of C-17 (6=58.3-65.2), C-1 (6=82.5-84.7)
and 17-CH3 (6= 18.3-20.4) are also clearly shifted downfield. The above data indicate that (4) is the A'*-olefin.
The molecular ion in the FD mass spectrum
( M += 1071) is consistent with the empirical formula
(CS3H,,N,0,3Co). The base peak (1019) corresponds to
M+-2CN.
Received: April IS, 1981 [Z 915 IE]
German version: Angew. Chem. 93. 1076 (1981)
111 B. Dresow. G. Schlingrnann, W . S.Sheldrick. V. B. Koppenhagen, Angew.
Chem. 92. 303 (1980); Angew. Chem. Int. Ed. Engl. 19. 321 (1980).
[21 B. Dresow. G . Schlingrnann. L. Ernsf. V. B . Koppenhagen. J. Biol. Chem.
255, 7637 (1980).
131 L. E m s f . Liebigs Ann. Chem. 1981. 376.
Angew. Chem. In!. Ed. Engl. 20 (1981) No. 12
we obtained p-alkylidene complexes as major products
(50-60%). The p-methylene complex (2) is formed in both
cis-form ( 2 4 as well as the trans-form (26); both isomers
can be isolated in the pure state by means of low-temperature chromatography. The same holds for the p-ethylidene
complex (3). The cis- and trans-isomers differ slightly in
their solubility in apolar solvents (as expected the transform is the more soluble). (2a) and (Zb) are found to be in
equilibrium ( = 3 :1) in solution at room temperature; at
-80°C the solutions of the pure isomers are stable. ( 2 4
exists in two modifications in the solid state [(2a) and (2a')]
whose 'H-NMR spectra are identical. The compounds
(2)-(4) were characterized by elemental analysis and by
their IR, 'H-NMR, I3C-NMR and mass spectral4], and, in
the case of the cis-isomer (2a), also by X-ray structure analysis (Fig.
Besides the p-alkylidene complexes we were able, in
each case, to isolate organometal-substituted ylides (5);
the species (6) could be detected only by mass spectroscopy. The preparation of p-alkylidene complexes via phosphorus ylides is new (syntheses with diazaalkanesL6]or dihalo alkane^['^ are known).
['I Prof. Dr. M.
L. Ziegler, Dip].-Chem. R. Korswagen, R. Alt, D. Speth
Anorganisch-chemisches Institut der UniversitBt
Im Neuenheimer Feld 270, D-6900 Heidelberg 1 (Germany)
I**] This work was supported by the Deutsche Forschungsgemeinschaft and
the Fonds der Chemischen Industrie.
0 Verlag Chemie GmbH. 6940 Weinheim. 1981
0570-0833/81/1212-1049 S 0.2.50/0
1049
solution of n-butyllithium in n-hexane until a clear orange
solution is formed. After addition of I g (2.82 mmol) of ( I )
the mixture is heated under reflux for 24 h (10 h with dioxane as solvent). 10 g silica gel (0.05-0.2) is added to the
solution, which is then evaporated down in a rotary evaporator. The brown residue is extracted with 200 ml of diethyl ether and the deep-red solution "prechromatographed" on a column (A1203 neutral, activity 1; 20 x 3.5
cm, ether). The first, yellow fraction contains Ph3P and a
little ferrocene. The second, violet and third, orange-red
zones are rechromatographed (A1,03 neutral, activity 1,
25 x 2.5 cm, ether) together at - 20 " C . Elution of a small
amount of Ph3P is followed by a violet, second zone conFig. I . ORTEP diagram of the p-methylene complex (20): the thermal elliptaining (2b). whose eluate is collected under N2 at - 50 "C.
soids correspond to a probability of 50%.
The bright-orange, third zone contains (5), R = H, the redorange, fourth zone ( 2 4 , which is eluted under the same
The manganese complex (7b) reacts with methylene- o r
conditions as (2b). Each of the solutions is evaporated
benzylidenephosphoranes in a ligand exchange reaction to
down to ca. 25 mL under high vacuum at -50°C and
give (q5-CH3C5H,)Mn(C0)2-CHRPR;"b1 and with trimetreated with 25 mL n-pentane. After a few days over dry
ice, red-violet and cherry-red crystals of (2a) and (2d). rethyl(methylene)phosphorane, after photolysis of an intermediate formed by peripheral ligand substitution at a C O
spectively, and dark violet crystals of (26) separate out. The
group, to give ( T ~ ' - C H ~ C ~ H , ) M ~ ( C O ) ~ - C H ~ PWe
M ~ , ~ ~ ~complexes
'.
are air-stable at room temperature; the total
have now reacted the complexes (7) under reflux in tetrayield of ( 2 4 and (26) [m.p. 168--170°C (dec.)] is 600 mg
hydrofuran (THF) with Ph3P=CH2 (Scheme 2).
(63%).
(q5-RC5H4)Mn(CO)zPPh3
(8)
+
( q 5 - R C 5 H 4 ) M n ( C 0 ) ,+ P h 3 P = C H z . LiBr
2
PhzP(C&-o-COCH3)
THF
+
(71
(a), R
= H,
(9)
( s 5 - R C 5 H 4 ) M n ( C O ) z [ P h 2 P ( C ~ H ~ ~ ~ - C O C(10)
H3)]
( b ) , R = CH3
Scheme 2
The compounds (9) and (10) were characterized by elemental analysis and by IR, N M R and mass spectra[81;in
the case of complex (106) also by an X-ray structure analysis'']. In the course of their formation a phenyl ring of the
Ph3P unit was acylated in the ortho-position; the acylation
product (9) is present, both bonded as ligand in (10). as
well in the free state.
The phosphane-complexes (8) were identified on the basis of data in the literature. The mechanism of the reaction
is still unclear. Participation not only of the ylide but also
of a C O group is evident.
Preparation of (104 [(lob)analogously]: (7a) is allowed
to react with the ylide, as described for (I). After prepurification on the column the filtrate still contains unreacted
(7a) besides the products ( 8 4 , (9) and (100). The ether solution is evaporated down to 50 mL and, after addition of
50 mL of n-pentane, cooled to - 6 0 ° C ; besides (IOa)
mainly (7a) and (9) crystallize out (the mother liquor contains (70) together with (8a) and PPh,). The mixture of
crystals is dissolved in ether (10 mL) and separated by preparative TLC (20 x 20 x 0.2 cm, silica gel 60, cyclohexane/
diethyl ether = 1 : 1). The yellow, first zone contains (7a)
and ( 8 4 , the yellow, second zone (9), and the likewise yellow, third zone (IOU).-The air-stable crystals of (1Oa) and
of (IOb) melt at 168 and 17O"C, respectively, with decomposition; (9) melts at 143°C. The yields of (100) and (106)
are 2 and 6%, respectively.
1YJ
Received: October 20, 1980 [Z 91 I IE]
revised: March 24, 1981
German version: Angew. Chem. 93. 1073 (1981)
Fig. 2. ORTEP diagram of the peripherically acylated phosphane-complex
(lob); the thermal ellipsoids correspond to a probability of 50%.
Procedure
Preparation of (2a) and (2b): A suspension of
[Ph,PCH,]Br (2 g, 5.65 mmol) in anhydrous T H F (100 mL)
under an atmosphere of N2 is treated dropwise with a 15%
1050
0 Verlag Chemie GmbH. 6940 Weinheim. 1981
CAS Registry numbers:
( I ) , 12154-95-9: (20). 79838-80-8;(26). 79896-43-8; (30). 79897-17-9; 136).
75829-77-5;(4), 79838-81-9;(5). R = H, 79839-82-0;(5), R=CH,, 79839-83-1;
(5). R=n-C,H,, 79839-84-2;(6),79839-85-3;(70). 12079-69-5;(7b). 12108-133 ; (8a). 12100-41-3; (8b), 12100-95-7;(9). 50777-63-4;(IOa). 79839-86-4;(lob).
79839-87-5;[PhxPCHTIBr 1779-49-3; Ph3P=CH? 3487-44-3: PhxP= CHCHi
1754-88-7; Ph3P==CH-n-C3H7,3728-50-5
[I] a) L. Knoll. J. Organomet. Chem. 148. C25 (1978);b) 193. 47 (1980).
[2] J . C. Baldwin. N . L. Keder. C. E. Strouse. W. C. Kaska. Z. Naturforsch. B
35, 1289 (1980).
[3] a) W. C. Kaska. D . K . Mitchell. R. F. Reicheldetfer. W. D. Korte. J. Am.
Chem. SOC.96. 2847 (1974): b) H . 5luu. W. Maiisch. Angew. Chem. 92.
1063 (1980);Angew. Chem. Int. Ed. Engl. 19. 1019 (1980).
0570-0833/81/1212-1050 $ 02.50/0
Angew. Chem. Inl. Ed.
Ens! 20 (1981) No. 12
141 IR, v( ( > [cm- '1: crystals (Nujol, KBr) of (20) 1998 sh, 1962 vs, 1940 s, I825
w, 1775 s, 1745 s; (2d) 1994 sh, 1973 vs, 1932 s, 1820 m, 1738 vs; (26) 1998
m, 1952 vs, 1930 s, 1802 sh, 1780 s. In CH2CIZsolution: 1985 vs, 1943 s,
1782 s (cidtrans 3: I).-'H-NMR, &values (300 MHz, CDCI, solution,
int. TMS, room temperature): (2a) 10.29 (s, 1 H), 8.38 (5, 1 H), 4.74 (s,
10 H); (26) 9.54 (s, 2 H), 4.77 (s, ]OH).-MS, m / z t (2a) 340 (molecular ion,
16.5%); (26) 340 (molecular ion, 30%).
151 Monoclinic crystals from ether/pentane, C;,,-P2,/n, a=900.0(12), b=
2277.2(22), c=656.7(16) pm,
103.69(27)", 2 = 4 , 752 reflections
(1>3o(I)), preliminary R value 0.098.
161 W. A. Herrmann. Angew. Chem. 90. 855 (1978); Angew. Chem. Int. Ed.
Engl. 17. 800 (1978); W. A. Herrmann. J. Planck. D.Riedel, M. L. Ziegler,
K. Weidenhammer, E. Guggolz. 8. Balbach. J. Am. Chem. Soc. 103. 63
(1981); W. A. Herrmann, P. Planck, 2. Naturforsch. 885,680 (1980).
171 C. E. Sumner Jr.. P. E. Reley. R. E. Davis, R. Pettit, J. Am. Chem. SOC.
102. 1752 (1980).
[8] iR [cm-'1: (IOa) vco 1927 vs, 1867 vs, 1855 vs, 1830 sh, vcocH, 1690 m;
(106)v,.<> 1922 vs, 1863 vs, 1852 vs, 1830 sh, v ~ . 1690
~ ~s.-'H-NMR
~ ,
(300 MHz, 6-values, int. TMS, 20°C): (IOU) 7.89 (m, 1 H), 7.46, 7.32 (m,
13H),4.34(s,SH), 1.89(s,3H);(lOb)7.89(br,lH),7.42,7.30(m,13H),
4.16 (d, 4H), 1.96 (s, 3H), 1.92 (s, 3H).--"P-NMR (90 MHz, 6-values.
CDCI,, H,PO, ext.): (lob) 95.92 (br).-MS, m / z : (106)494 (molecular ion,
3.5%); (9) 304 (molecular ion, 100%).
[9] Tetragonal crystals from ether/pentane, C:-P4,,
a = 1003.5(4),
c=2392.2(9) pm, 2 = 4 ; 779 reflections (1>2.50-(1)),R,=0.046.
and pol yether components of these crown ethers, the benzene rings (x-donors) in DB24C8, DB30C10, and
DB36C12 all enter into stabilizing charge-transfer (CT) interactions with the aromatic rings of the bipyridyl Iigand
(n-acceptor).
o=
F-,
c,
%&,,
Second Sphere Coordination of Cationic Platinum
Complexes by Crown EthersThe X-Ray Crystal Structure of IPt(bpy)(NH,),.
Dibenzol3Olcro~n-l01~+[PF~I;
-rHzO (x = 0.6)'**]
By Howard M. Colquhoun, J. Fraser Sioddari,
David J. Williams, John B. Wolstenholme, and
Ryszard Zarzycki'']
Since the possibility of second sphere coordinationc2]of
transition metal complexes was first alluded to by Werner"! in 1913, it has become apparentI3' that the binding of
an outer layer of ligands to transition metal (M) ammine
complexes is usually a result of (N-H-. . X ) hydrogen
bonding between the NH3 ligands and electron donor
atoms (X) present in counterions, solvent molecules, or
other ligands. The fact that [18]crown-6 (18C6) and dibenzo-[l8]crown-6 (DB18C6)14] form strong adducts with primary alkylammonium (RNH:) ions through multiple hydrogen bonding suggested''] to us that coordinated ammonia (M-NH;+) should bind to crown ethers in a similar manner. Indeed, we have been able to isolate[61the crystalline adducts, [trans-PtC12(PMe3)NH3.DB18C61 and
[(tran~-PtCl,(PMe,)(NH~)}~.
18C61, and have demonstrated['] that the macrocyclic polyethers serve as second
sphere ligands via (N-H.. .O) hydrogen bonding to NH3
ligands in the first sphere.
We now report on the ability of the [Pt(b~y)(NH~)~l'+
ion to form 1 :1-adducts with 18C6, DB18C6, DB24C8,
DB30C10, and DB36C12L71.In addition to the expected
(N-H.. .O) hydrogen bond formation between the cisNH3 ligands on Pt" having a square planar environment
['I
Dr. H. M. Colquhoun
Corporate Laboratory, Imperial Chemical Industries Ltd.
P.O. Box 11, The Heath, Runcorn, Cheshire WA7 4QE (England)
Dr. J. F. Stoddan [+I, J. B. Wolstenholme
Department of Chemistry, The University
Sheffield S3 7HF (England)
Dr. D. J. Williams, R. Zanycki
Chemical Crystallography Laboratory
Department of Chemistry, Imperial College
London SW7 2AY (England)
['I Author to whom correspondence should be addressed.
[**I The work was supported in part by the Science Research Council (United Kingdom).
Angew. Chem. Int. Ed. Engl. 20 (1981) No. 12
'
Fig. I. Computer drawing of a space-filling molecular model based on the
crystal structure of the 1 : I-adduct formed between [Pt(bpy)(NH,)J2+ and
DB30C10. Direct visual comparison with the representation of the structure
shown in Figure 2 is necessary in order to appreciate the structural detail.
Crystals of [Pt(bpy)(NH3),(DB30C10)]2+[PF,]; .ca. 0.6 H 2 0 are monoclinic;
space group FT,/n, a = 16.081(2), b = 15.912(2), c = 18.718(2) A,
fl- 101.34(1)0, V=4696 A3, Z=4,pC=1.74 g c m - ' , p ( C ~ ~ , ~ ) = 7cm-'.
2
Of
the 5250 independent reflections (OG SO", CuK,.irradiation), 453 were classified as unobserved. The structure was solved by the heavy atom method and
refined anisotropically with absorption corrected data to R -0.053.
Fig. 2. Crystal structure of [Pt(bpy)(NH3)2(DB30C10)]2'[PF6]~'ca. 0.6H20.
Bond lengths [A] in the host molecule: C--C (excluding CA,,,-C), 1.391.45; C,,,,-O, 1.35-1.37. Bond angles I") in the host molecule: COC (excluding CArYIOC),
110- 115; CA,,IOC: 116-1 18. Tonion angles I"] (OCCO
and CCOC) in the host are shown beside the relevant CC and CO bonds in
A; angles (6, and &) bethe structure. Hydrogen bond distances, R,
tween COC planes and a) the NO vectors and b) the HO vectors:
RN4 (,,=3.02, a) 36, b) 37; RN4. 0,0=2_90,a) 0, b) 14; RN3 <,lu=2.99,a)
15, b) 24; RN4 . F =3.20 (hydrogen atoms were located unambiguously). (In
the case of N4, a rigid body refinement of the NH, ligand was possible. Since
the thermal parameters were anisotropic for N3, rigid body refinement of the
NHI ligand was not possible; however, the H atom involved in hydrogen
bonding to 0 1 9 was identified from the difference map.) Separations [A] between aromatic rings in the guest and host: bpy-benzene ring (14/38)=3.45
(minimum), 3.47 (average); bpy-benzene ring (29/34)=3.48 (minimum). 3.52
(average). Angles
between the planes of the aromatic rings: bpy-benzene
ring (14/38)=0.9; bpy-benzene ring (29/34)=2.2; benzene ring (14/38)-benzene ring (29/34)= 1.4.
8 Verlag Chemie GmbH. 6940 Weinheim, 1981
r]
0570-0833/81/1212-1051 $02.50/0
1051
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carbonyl, reaction, unexpected, complexes, cyclopentadienyl, preparation, alkylidene, acylation, metali, novem, ylide, access, phosphorus
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