Products of the reactions of 2-diazomalonate and of 2-diazoindanedione with germylenes and stannylenes

Article abstract of DOI:10.1021/om950599p

Products obtained in the reaction between germylenes or stannylenes with dimethyl 2-diazomalonate and 2-diazo-1,3-indanedione have been isolated and characterized. Compounds thus prepared are the 2H-1,3,4,2-oxadiazagermanine-5-carboxylates 1 and 2, the in

Full text of DOI:10.1021/om950599p

408
Organometallics 1996, 15, 408-414
P r od u cts of th e Rea ction s of 2-Dia zom a lon a te a n d of
2-Dia zoin d a n ed ion e w ith Ger m ylen es a n d Sta n n ylen es
Gu¨nter Ossig, Anton Meller,* Stefanie Freitag, Olaf Mu¨ller,
Heinz Gornitzka, and Regine Herbst-Irmer
Institut fu¨r Anorganische Chemie der Universita¨t Go¨ttingen,
Tammannstrasse 4, D-37077 Go¨ttingen, Germany
Received August 1, 1995X
Products obtained in the reaction between germylenes or stannylenes with dimethyl
2-diazomalonate and 2-diazo-1,3-indanedione have been isolated and characterized. Com-
pounds thus prepared are the 2H-1,3,4,2-oxadiazagermanine-5-carboxylates 1 and 2, the
indeno[2,1-e]-1,3,4,2-oxadiazametallanin-5(2H)-ones 7 and 8, the 6-oxa-3,4-diaza-2,7-
digermabicyclo[3.2.0]hept-3-ene-carboxylate 3, resulting from the thermal treatment of 2,
and the unsymmetrical dimer of 7, (7)2. Furthermore the reaction products of 2 with
t-BuNCO, 4, with PhCHO, 5, and with H2CdCHCHO, 6, and compound 9 obtained by partial
hydrolysis of 7 and (7)2 were isolated. The compounds were characterized by NMR
spectroscopy (1H, 13C, and 29Si and in part 15N and 119Sn), MS (EI or FI), and elemental
analyses. X-ray crystal structure determinations are presented for 1, 2, 3, 4, and (7)2.
Sch em e 1
In tr od u ction
In 1987 the formation of a first example of a stable
germaimine was described from the reaction of bis[bis-
(trimethylsilyl)amino]germane(II) with 2-diazomalon-
ate.1,2 It was reported that the reaction led to the
transoid isomer of the germaimine (C), which in solution
upon storage at room temperature converted to the
cisoid conformer (D) (Scheme 1).
Structural assignments have been done in accordance
with 1H- and 13C-NMR data and are supported by
MNDO calculations. Later on a cyclic equilibrium
structure (E) was also considered (based on MNDO
results3,4 ) by the interaction of one of the CdO groups
with the germanium atom. The MNDO calculations
using a simplified model (SiH3 for SiMe3, gas phase at
0 K) resulted in enthalpies of formation of ∆Hf ) -590
Resu lts a n d Discu ssion
As C and D were only reported in solution but not in
the solid state, we suspected that these compounds
might be somewhat difficult to crystallize. Therefore
F 9 was reacted with diazomalonic acid dimethylate,10
B, according to eq 1. The melting point of F is 84-85
kJ /mol for the germaimine structure (C) but ∆Hf
)
-775 kJ /mol for E.5,6
E however cannot be considered as a germaimine
anymore. Apparently no further attempts have been
made by the original authors to isolate any of the
discussed compounds. As we are concerned with the
chemistry of germaimines ourself,7,8 we were interested
in characterizing the products of the reactions of ger-
mylenes with diazo compounds with additional data
including X-ray structure determinations.
X Abstract published in Advance ACS Abstracts, December 1, 1995.
(1) Glidewell, C.; Lloyd, D.; Lumbard, K. W.; McKechnie, J . S.
Tetrahedron Lett. 1987, 28, 343.
(2) Glidewell, C.; Lloyd, D.; Lumbard, K. W. J . Chem. Soc., Dalton
Trans. 1987, 501.
(3) Glidewell, C. Struct. Chem. 1990, 1, 317.
(4) Glidewell, C.; Lloyd, D.; Wiberg, N. Struct. Chem. 1990, 1, 151.
(5) Glidewell, C.; Lloyd, D.; Lumbard, K. W.; McKechnie, J . S.;
Hursthouse, M. B.; Short, R. L. J . Chem. Soc., Dalton Trans. 1987,
2981.
(6) Glidewell, C.; Hursthouse, M. B.; Lloyd, D.; Lumbard, K. W.;
Short, R. L. J . Chem. Res. (S) 1986, 434; J . Chem. Res. (M) 1986, 3501.
(7) Pfeiffer, J .; Maringgele, W.; Noltemeyer, M.; Meller, A. Chem.
Ber. 1989, 122, 245.
°C, and the melting point of A,11 bis[bis(trimethylsilyl)-
amino]germane(II) (used in ref 1), is only 33 °C.
Compound 1 was obtained in 55% yield by repeated
(8) Meller, A.; Ossig, G.; Maringgele, W.; Stalke, D.; Herbst-Irmer,
R.; Freitag, S.; Sheldrick, G. M. J . Chem. Soc., Chem. Commun. 1991,
1123.
(9) Meller, A.; Gra¨be, C.-P. Chem. Ber. 1985, 118, 2020.
(10) Regitz, M. Chem. Ber. 1966, 99, 3128.
0276-7333/96/2315-0408$12.00/0 © 1996 American Chemical Society

Reactions of Germylenes and Stannylenes
Organometallics, Vol. 15, No. 1, 1996 409
F igu r e 2. Crystal structure of 2 with anisotropic displace-
ment parameters depicting 50% probability. The hydrogen
atoms have been omitted for clarity.
F igu r e 1. Crystal structure of 1 with anisotropic displace-
ment parameters depicting 50% probability. The hydrogen
atoms and the single lattice hexane molecule have been
omitted for clarity.
crystallization from hexane at -25 °C. However in
solution 1 is in equlibrium with F and B and this
equilibrium is shifted in the direction of the educts upon
raising the temperature. This can be observed from the
1
intensity of the H-NMR signals of F and 1. 1 forms
orange-red crystals which decompose above 40 °C.
An X-ray crystal structure analysis confirms its
structure as methyl 2,2-bis[2,6-diisopropyl-N-(trimeth-
ylsilyl)anilino]-6-methoxy-2H-1,3,4,2-oxadiazagermanine-
5-carboxylate (Figure 1). No other products are formed
in the reaction (eq 1).
F igu r e 3. Crystal structure of 3 with anisotropic displace-
ment parameters depicting 50% probability. The hydrogen
atoms have been omitted for clarity.
Accordingly 2 was obtained from the reaction of B and
A (eq 2). The NMR data for 2 correspond perfectly to
those reported1,2 for C (for which a transoid germaimine
structure was claimed) and are distinctly different from
those reported for D. 2 forms orange-red crystals from
hexane at -25 °C in 95% yield within 16 h. The
structure of 2 has been confirmed by an X-ray-structure
analysis (Figure 2). 2 is thermally more stable than 1;
it melts without decomposition at 84 °C. The 15N-NMR
signals of the NdN group in 2 appear at δ +102 and δ
+184 ppm far away from the 15N-NMR signal of a
germaimine (δ -193 ppm).8 The 15N-NMR signal of the
N(SiMe3) groups in 2 at δ -331 ppm (comparable to
those of dihydro-1,3,4,2-oxadiazagermines2) excludes
any ylidic form as postulated for E. It can be concluded
from the 15N-NMR and the 13C-INADEQUATE data
(1J (13C-13C) ) 85.1 Hz for the sp2-hybridized C atoms)
that conjugation effects in 2 are minimal. We did find
F igu r e 4. Crystal structure of 4 with anisotropic displace-
ment parameters depicting 50% probability. The hydrogen
atoms and the hexane molecule have been omitted for
clarity.
al. to the cisoid isomer of the germaimine D in solution
but could not isolate a corresponding substance in a
pure state. However, as these signals appear1,2 upon
storing the 2H-1,3,4,2-oxadiazagermanine-5-carboxylate
2 (tE), which is thermodynamically more stable than
D, the latter structure can be excluded.
At elevated temperatures decomposition of 2 is ob-
served in solution. Upon heating of 2 in hexane for 4 h
and slow evaporation of the solvent colorless crystals
(11) Gynane, M. J . S.; Harris, D. H.; Lappert, M. F.; Power, P. P.;
Rivie`re, P.; Rivie`re-Baudet, M. J . Chem. Soc., Dalton Trans. 1977,
2004.
1
the H- and 13C-NMR signals assigned by Glidewell et

410 Organometallics, Vol. 15, No. 1, 1996
Ossig et al.
of 3 were obtained, formed according eq 3. The result
discern if ring opening of 2 is induced by the formation
of a donor bond from the reaction partner (thus includ-
ing a five-coordinate transition state at the germanium
atom) or by an equilibrium reaction proceeding via
minimal amounts of D and A. In the formation of 3 (at
elevated temperatures) the intermediate G is a convinc-
ing assumption regardless if its formation (in solution)
involves intermolecular coordination between two mol-
ecules of 2 or the formation of A in the first step. For
4 an X-ray structure analysis was performed (Figure
4). For 5 and 6 δ(13C) ∼ 103 ppm for the endocyclic
CdN atoms indicates conjugation in the six-membered
rings.
of an X-ray structure analysis is depicted in Figure 3.
The diazomalonate that split off was isolated by high-
vacuum distillation at 35 °C. We were not successful
in the attempted characterization of the remaining oily
residue.
Although 2 is not a germaimine, it reacts with tert-
butyl isocyanate, benzaldehyde, and acrolein to products
which would be expected from a moiety containing a
GedN double bond (eq 4). Apparently the [2 + 2]
For comparison purposes we reacted as well bis[bis-
(trimethylsilyl)amino]germanium(II) and -tin(II) with
2-diazo-1,3-indanedione12 according to eq 5, thus obtain-
cycloadditions to give 4 and 5 and the [2 + 4] cycload-
dition leading to 6 proceed via ring opening and isomer-
ization of 2 induced by formation of an O-Ge bond with
the reagent. The same mechanism appears to be true
for the addition product reported for C (or D) with weak
acids.5 In this connection one of the reviewers proposed
the following interesting mechanism:
ing the corresponding indeno[2,1-e]-1,3,4,2-oxadiaza-
metallanin-5(2H)-ones 7 and 8. Besides 7 also a dimeric
compound (7)2 crystallized at -25 °C forming an olive
solid; by different crystallization procedures, crystals of
monomeric (yellow) and dimeric (green) 7 could be
separated. At ambient temperature in solution NMR
signals of the dimer (7)2 are recorded. The signals of
the monomeric 7 appear in addition to those of (7)2 upon
heating in CDCl3 to 50 °C. This means that, in addition
to the 22 13C-resonances for (7)2, 10 more signals for 7
are observed. In the 15N-NMR spectrum of (7)2 there
are 8 signals. Four of them (δ -333.2 to -328.5) can
be assigned unequivocally to the (TMS)2N substituents.
For the remaining four signals we tentatively propose
the following assignments: δ -61.4 (N(7)), 19.4 (N(8)),
163.6 (N(6)), 191.1 (N(5)). In contrast to that, 8 is only
obtained in the monomeric form. An X-ray crystal
structure analysis gave an unexpected structure for (7)2
which includes a four- and a five-coordinated germa-
nium atom (Figure 5).
This mechanism rests upon the assumption that there
could be an equilibrium between 2 and the cisoid
germaimine D from which D is removed continuously
by the reaction with the germylene A. The product of
this reaction would be G (perhaps the unidentified
species which has been claimed to be the cisoid ger-
maimine D1,2). This mechanism also gives a conclusive
explanation for the formation of 3. On the other hand,
we find that the substance (still unidentified) which
gives the NMR data ascribed for D is colorless whichsin
our opinionsexcludes structure G. Furthermore the
NMR spectra of 2 do not exhibit even traces of signals
which could be attributed to D. Finally we do not find
3 as a product, if we perform the reactions and manipu-
lations at ambient temperature. It will be difficult to
The partial hydrolysis of 7 and (7)2 (in toluene) gave
9. In the dimerization of compound 7, the first step
probably is the formation of a donor bond from a
carbonyl group (on C(102)) to Ge(1) which results in
(12) Regitz, M.; Schwall, H.; Heck, G.; Eistert, B.; Bock, G. Chem.
Ber. 1966, 99, 125.

Reactions of Germylenes and Stannylenes
Organometallics, Vol. 15, No. 1, 1996 411
Ta ble 1. Selected Bon d Len gth s (p m ) a n d An gles (d eg) for 1-4 a n d (7)2
Compound 1
Ge(1)-N(4)
Ge(1)-N(3)
180.6(2)
181.1(2)
Ge(1)-N(1)
Ge(1)-O(4)
187.0(2)
187.7(2)
N(1)-N(2)
N(2)-C(1)
126.6(3)
138.3(3)
C(1)-C(4)
C(4)-O(4)
138.6(3)
129.9(3)
N(4)-Ge(1)-N(3)
N(4)-Ge(1)-N(1)
N(3)-Ge(1)-N(1)
120.87(8)
108.31(8)
115.25(8)
N(4)-Ge(1)-O(4)
N(3)-Ge(1)-O(4)
N(1)-Ge(1)-O(4)
109.42(8)
101.80(8)
98.38(7)
N(2)-N(1)-Ge(1)
N(1)-N(2)-C(1)
N(2)-C(1)-C(4)
122.3(2)
126.5(2)
125.7(2)
O(4)-C(4)-C(1)
C(4)-O(4)-Ge(1)
124.5(2)
122.52(14)
Compound 2
Ge(1)-N(4)
Ge(1)-N(3)
180.3(2)
181.2(2)
Ge(1)-O(4)
Ge(1)-N(1)
186.3(2)
188.0(2)
N(1)-N(2)
N(2)-C(1)
126.5(3)
139.2(3)
C(1)-C(4)
C(4)-O(4)
139.1(3)
130.4(3)
N(4)-Ge(1)-N(3)
N(4)-Ge(1)-O(4)
N(3)-Ge(1)-O(4)
119.18(9)
106.63(8)
104.43(8)
N(4)-Ge(1)-N(1)
N(3)-Ge(1)-N(1)
O(4)-Ge(1)-N(1)
112.11(9)
113.35(9)
98.32(8)
N(2)-N(1)-Ge(1)
N(1)-N(2)-C(1)
C(4)-C(1)-N(2)
119.0(2)
126.7(2)
124.4(2)
O(4)-C(4)-C(1)
C(4)-O(4)-Ge(1)
124.3(2)
119.8(2)
Compound 3
Ge(1)-N(2)
Ge(1)-N(1)
Ge(1)-N(6)
184.0(3)
184.6(3)
186.7(3)
Ge(1)-N(5)
Ge(2)-N(3)
Ge(2)-O(4)
189.0(3)
181.9(3)
182.8(2)
Ge(2)-N(4)
Ge(2)-N(6)
N(5)-C(1)
183.0(3)
188.5(3)
126.4(4)
C(1)-C(4)
C(4)-O(4)
C(4)-N(6)
155.1(5)
141.0(4)
145.6(4)
N(2)-Ge(1)-N(1)
N(2)-Ge(1)-N(6)
N(1)-Ge(1)-N(6)
N(2)-Ge(1)-N(5)
N(1)-Ge(1)-N(5)
N(6)-Ge(1)-N(5)
111.82(12)
114.15(12)
122.70(11)
110.39(12)
102.64(12)
91.67(11)
N(3)-Ge(2)-O(4)
N(3)-Ge(2)-N(4)
O(4)-Ge(2)-N(4)
N(3)-Ge(2)-N(6)
O(4)-Ge(2)-N(6)
109.05(11)
115.14(12)
112.24(11)
124.13(12)
75.06(10)
N(4)-Ge(2)-N(6)
C(1)-N(5)-Ge(1)
N(5)-C(1)-C(4)
O(4)-C(4)-N(6)
O(4)-C(4)-C(1)
113.52(12)
108.6(2)
118.5(3)
104.2(2)
117.2(3)
N(6)-C(4)-C(1)
C(4)-N(6)-Ge(1)
C(4)-N(6)-Ge(2)
Ge(1)-N(6)-Ge(2)
C(4)-O(4)-Ge(2)
108.9(3)
105.3(2)
87.3(2)
161.2(2)
91.0(2)
Compound 4
Ge(1)-N(2)
Ge(1)-N(1)
Ge(1)-N(4)
180.7(2)
181.2(2)
188.3(2)
Ge(1)-O(1)
Ge(1)-O(5)
O(1)-C(13)
194.2(2)
215.5(2)
134.4(4)
C(13)-N(3)
C(13)-N(4)
N(4)-N(5)
124.8(4)
143.9(4)
129.8(3)
N(5)-C(18)
C(18)-C(21)
C(21)-O(5)
131.0(4)
145.5(4)
123.6(4)
N(2)-Ge(1)-N(1)
N(2)-Ge(1)-N(4)
N(1)-Ge(1)-N(4)
N(2)-Ge(1)-O(1)
N(1)-Ge(1)-O(1)
123.74(11)
119.62(11)
116.53(11)
102.21(10)
100.92(10)
N(4)-Ge(1)-O(1)
N(2)-Ge(1)-O(5)
N(1)-Ge(1)-O(5)
N(4)-Ge(1)-O(5)
O(1)-Ge(1)-O(5)
68.34(9)
91.11(10)
94.19(10)
80.91(9)
149.19(8)
C(13)-O(1)-Ge(1)
O(1)-C(13)-N(4)
N(5)-N(4)-C(13)
N(5)-N(4)-Ge(1)
C(13)-N(4)-Ge(1)
95.6(2)
N(4)-N(5)-C(18)
N(5)-C(18)-C(21)
O(5)-C(21)-C(18)
C(21)-O(5)-Ge(1)
121.0(3)
123.3(3)
124.5(3)
127.9(2)
101.0(2)
123.0(2)
140.1(2)
95.0(2)
Compound (7)2
Ge(1)-N(2)
Ge(1)-N(1)
Ge(1)-O(2)
Ge(1)-N(7)
Ge(1)-O(3)
Ge(2)-N(4)
181.3(4)
183.2(4)
186.0(3)
205.3(4)
215.8(3)
181.5(5)
Ge(2)-N(3)
Ge(2)-O(1)
Ge(2)-N(6)
N(5)-N(6)
N(5)-C(101)
O(1)-C(100)
181.9(5)
183.6(4)
189.6(5)
129.0(6)
138.2(7)
134.2(6)
C(100)-C(101)
C(101)-C(102)
C(102)-O(2)
C(102)-N(8)
N(7)-N(8)
136.8(7)
152.2(7)
137.4(6)
152.1(6)
125.5(5)
N(7)-C(402)
O(3)-C(401)
C(401)-C(402)
C(402)-C(403)
C(403)-O(4)
135.7(6)
125.5(6)
139.8(7)
145.8(7)
121.9(6)
N(2)-Ge(1)-N(1) 121.0(2)
N(2)-Ge(1)-O(2) 102.6(2)
N(1)-Ge(1)-O(2) 101.7(2)
N(2)-Ge(1)-N(7) 119.2(2)
N(1)-Ge(1)-N(7) 118.1(2)
O(2)-Ge(1)-N(7) 77.9(2)
N(2)-Ge(1)-O(3) 91.3(2)
N(1)-Ge(1)-O(3) 88.1(2)
N(4)-Ge(2)-N(3)
N(4)-Ge(2)-O(1)
N(3)-Ge(2)-O(1)
N(4)-Ge(2)-N(6)
N(3)-Ge(2)-N(6)
O(1)-Ge(2)-N(6)
N(6)-N(5)-C(101)
N(5)-N(6)-Ge(2)
116.8(2) O(1)-C(100)-C(101)
107.0(2) C(100)-C(101)-N(5)
127.9(5) C(402)-N(7)-Ge(1)
128.6(5) N(7)-N(8)-C(102)
115.2(3)
109.9(4)
118.5(3)
110.1(3)
123.5(5)
113.3(4)
135.7(5)
104.0(2) C(100)-C(101)-C(102) 109.8(5) C(102)-O(2)-Ge(1)
111.4(2) N(5)-C(101)-C(102)
112.9(2) O(2)-C(102)-N(8)
103.3(2) O(2)-C(102)-C(101)
122.9(5) N(8)-C(102)-C(101)
120.2(4) N(8)-N(7)-C(402)
121.6(5) C(401)-O(3)-Ge(1)
111.0(4) O(3)-C(401)-C(402)
117.0(4) N(7)-C(402)-C(401)
104.3(4) N(7)-C(402)-C(403)
125.9(4) C(401)-C(402)-C(403) 110.5(5)
118.9(3) O(4)-C(403)-C(402) 128.8(5)
O(2)-Ge(1)-O(3) 155.21(14) C(100)-O(1)-Ge(2) 115.1(3) N(8)-N(7)-Ge(1)
N(7)-Ge(1)-O(3) 77.4(2)
switched from N(8) to N(7), N(8) now coordinating
C(102) (notice the long bond distance, 152.1 pm, between
N(8) and C(102)). Apparently this stabilization is
advanced by steric effects (from the exocyclic substitu-
ents) and electronic effects in the two five-membered
rings. Alternatively an intermolecular [2 + 2] cycload-
dition between the CdO group and an intermediately
formed GedN double bond can be discussed, followed
by the rearrangement of the four- and six-membered
rings into two five-membered rings.
Cr ysta l Str u ctu r es. Selected bond lengths and
angles are compiled in Table 1.
F igu r e 5. Crystal structure of (7)2 with anisotropic
displacement parameters depicting 50% probability. The
hydrogen atoms and the four lattice THF molecules have
been omitted for clarity.
In the structure of 1, the germanium atom is sur-
rounded by three nitrogen atoms and one oxygen atom
in a distorted tetrahedral environment. The angle
N(3)-Ge(1)-N(4) is widened due to steric reasons. The
six-membered GeN2C2O ring is nearly planar (mean
deviation 1.4 pm). The bond length between Ge(1) and
N(1) (187.0 pm) is longer compared to those between
pentacoordination on the Ge atom. The electron with-
drawal exerted on C(102) enables nucleophilic attack,
and in a concerted rearrangement the Ge-N bond is

412 Organometallics, Vol. 15, No. 1, 1996
Ossig et al.
or toluene-d8/CH3NO2 external); 119Sn (toluene-d8/SnMe4 ex-
ternal). Assignments of 13C signals were made using multiplet
selection (“Musel”, 62.89 MHz) or distortionless enhancement
by polarization transfer (DEPT, 100.60 MHz) methods where
necessary; 13C-13C coupling constants were evaluated by
INADEQUATE experiments. Mass spectra were obtained in
a Varian CH5 instrument (EI, 70 eV, and FI) and a Finnigan
MAT 8230 (EI, 70 eV) spectrometer.
Ge(1) and N(3) and N(4), respectively, and corresponds
to a single bond distance.5,7 The Ge(1)-O(4) distance
(187.7 pm) is on the upper limit of Ge-O bond lengths
observed in cyclic compounds containing tetracoordi-
nated germanium and two coordinated oxygen atoms
(169.0-187.5 pm).13 The bond distances between N(1)
and N(2) (126.6 pm) and C(1) and C(4) (138.6) represent
localized double bonds.
Bond lengths and bond angles in 2 are in full
accordance with those determined in 1, but the six-
membered ring shows a distorted boat conformation. Ge-
(1) and C(1) are positioned 45.9 and 12.1 pm above the
plane formed by N(1), N(2), C(4), and O(4).
Starting materials were prepared according to the following
references: [(2,6-iPr2C6H3)(Me3Si)N]2Ge,9 [(Me3Si)2N]2Ge,11 [(Me3-
Si)2N]2Sn,11 N2C(COOMe)2,10 N2C(CO)2C6H4.12
Meth yl 2,2-Bis[(2,6-d iisop r op ylp h en yl)(tr im eth ylsilyl)-
a m in o]-6-m eth oxy-2H-1,3,4,2-oxa d ia za ger m a n in e-5-ca r -
boxylate (1) an d Meth yl 2,2-Bis[bis(tr im eth ylsilyl)am in o]-
6 -m e t h o x y -2 H -1 , 3 , 4 , 2 -o x a d i a z a g e r m a n i n e -5 -
ca r boxyla te (2). To a stirred solution of 2.50 g of bis [(2,6-
diisopropylphenyl)(trimethylsilyl)amino]germane(II) (4.39 mmol
for 1) or 8.46 g of bis[bis(trimethylsilyl)amino]germane(II)
(21.51 mmol for 2) in 60 mL of hexane, the molar equivalents
of diazomalonic acid dimethylate (0.69 g for 1 at 0 °C, 3.40 g
for 2 at 22 °C) were added dropwise with a syringe through a
septum. The reaction mixtures have a red color; the one
leading to 1 turns yellow upon warming to ambient temper-
ature. 1 is obtained by threefold crystallization (overnight)
at -25 °C, manipulations performed below -20 °C. 2 is
obtained by a single crystallization at -25 °C. Single crystals
(of red color for both products) grow from highly diluted
solutions at -25 °C. 1: yield 1.77 g (2.43 mmol), 55%; orange-
red crystals decompose at 40-46 °C. 2: yield 11.31 g (20.52
mmol), 95%; orange-red crystals; mp 84 °C.
In 3 all bond lengths at the germanium atoms
correspond to covalent single bonds, while the distance
between C(1) and N(5) (126.4 pm) stands clearly for a
double bond.
In 4 the germanium atom is pentacoordinated (dis-
torted trigonal bipyramidally). The equatorial positions
are occupied by the nitrogen atoms, and the axial
positions, by the oxygen atoms. The Ge(1)-O(5) dis-
tance (215.5 pm) indicates a coordinative bond. In the
six-membered ring double bonds are localized between
the atoms N(5) and C(18) (131.0 pm) and C(21) and O(5)
(123.6 pm).14 The bond length between N(4) and N(5)
(129.8 pm) is remarkably shortened compared to a N-N
single bond (135.5 pm).13
The structure of (7)2 contains two Ge atoms: Ge(2) is
tetrahedrally coordinated like the germanium atom in
1 and 3. Ge(1) however exhibits pentacoordination, and
its geometry corresponds to the Ge atom of 4 (with the
oxygen atoms at axial positions). The six-membered
ring containing Ge(2) shows structural parameters
analogous to those in 1 and 2 (localized double bonds
between the nitrogen atoms N(5) and N(6) (129.0 pm)
and the carbon atoms C(100) and C(101) (136.8 pm)).
The bonding sphere around Ge(1) is somewhat confus-
ing. The Ge(1)-N(7) bond length (205.3 pm) exceeds the
Ge-N single bond distances in the structures of 1-4
by 20 pm which indicates a quite weak bond. The bond
between the Ge(1) and O(3) atoms (215.8 pm) corre-
sponds to the coordinative bond between O(5) and Ge-
(1) in 4. Normal covalent bonds exist between Ge(1)
and N(1), N(2), and O(2). With consideration of the
structural parameters a delocalized electron system
extending from N(8) via N(7), C(402), and C(401) to O(3)
is likely to be accepted; the bond length between N(8)
and C(102) is quite long (152.1 pm) compared to a
typical single bond (147 pm).14
1 is in equilibrium with its educts, depending upon tem-
perature (temperature, °C/% of 1): -20/27; -30/34; -40/41;
-50/44; -60/47; -70/47. 1H NMR (toluene-d8, -60 °C):
δ
3
-0.10, -0.06 (2s, each 9 H, SiMe3), 1.01 (d, J HH ) 6.5 Hz, 3
H), 1.084 (pseudo-t: 2 d at 1.076 + 1.093 Hz, J HH ) 6.5 Hz
3
each d, 6 H), 1.18 (pseudo-t: d at 1.19, 2nd d covered by educt,
6 H), 1.24 (pseudo-t: d at 1.23, 2nd d covered by educt, 6 H),
3
1.79 (d, J HH ) 6.3 Hz, 3 H) (CH(CH3)2), 3.09 (3J HH ) 6.6 Hz),
3.39 (3J HH ) 6.4 Hz), 3.67 (3J HH ) 6.6 Hz), 4.21 (3J HH ) 6.3
Hz) (4 br sept, each 1 H, CH(CH3)2), 3.53, 3.76 (2 s, each 3 H,
3
OMe), 6.67-6.76 (m, 2 H), 6.84 (d, J HH ) 7.3 Hz, 1 H), 6.88-
6.96 (m, 3 H) (C6H3) [C6H3 (-80 °C): δ 6.71 (pseudo-t, 2 H),
6.81 (d, 1 H), 6.87 (d, 1H), 6.92 (pseudo-t covered by AB2
spectra of educt, 2H)]. 13C NMR (toluene-d8, -40 °C): δ 1.78,
2.08 (SiMe3), 23.7 (covered), 23.84, 24.62, 24.68, 24.77, 25.44,
25.52, 25.93 (8 × CH(CH3)2), 27.51, 27.88 [(-60 °C): δ 27.88,
27.94 (2 × CH(CH3)2] (br, 2 C), 28.10 (CH(CH3)2), 51.27, 52.33
(OMe), 121.24 (OCdCN), 124.44 (C-3,3′,5,5′, 1-3, probably 2
signals missing for C-3,3′,5,5′), 126.47, 126.62 (C-4,4′), 140.00,
140.58 (C-1,1′), 146.16, 147.21, 147.46 (2 C) (C-2,2′,6,6′) ppm.
Signals of the educts {[(2,6-iPr2C6H3)(Me3Si)N]2Ge and N2C-
(COOMe)2}: δ 3.70 (SiMe3, 23.78, 25.83 (CH(CH3)2), 28.27 (CH-
(CH3)2, 51.67 (OMe), CdN2 not detected (24 °C: 65.81), 123.90
(C-3,5), 125.51 (C-4), 142.89 (br, C-1), 147.46 (C-2,6) (C6H3),
160.59 (br, CdO). 29Si NMR (toluene-d8, -40 °C): δ 15.24,
16.08 (2 s). MS (EI; 70 eV): m/ z (relative intensity) 570 (7)
[M - N2C(COOMe)2+], 322 (100) [iPr2C6H3NSiMe3Ge+]. MS
(FI) m/z 570 (100). Anal. Calcd for C35H58N4O4Si2 (727.63):
C, 57.78; H, 8.03; N, 7.70. Found: C, 57.79; H, 8.14; N, 7.65.
2. 1H NMR (C6D6): δ 0.23 (s, 36 H, SiMe3), 3.32, 3.71 (2 s,
each 3 H, 2 × O-Me. 13C NMR (C6D6): δ 4.84 (SiMe3), 51.10,
52.39 (2 × O-Me), 119.86 (OCdCN), 157.78 (OCdCN), 165.82
(CdO). 13C NMR (INADEQUATE, C6D6): 1J (CdC) ) 85.1 Hz,
Exp er im en ta l Section
All reactions were performed in an inert atmosphere of dry
nitrogen in dry solvents saturated with nitrogen. Melting
points were determined in sealed capillaries. Elemental
analyses were performed by Mikroanalytisches Labor Beller,
Go¨ttingen, Germany. NMR spectra were recorded on Bruker
AM-250 or MSL-400 instruments. Heteroelement spectra
were recorded in the proton-decoupled mode. Solvents and
standards used were as follows: 1H, 13C, 29Si (CDCl3/TMS
internal; C6D6 or toluene-d8/TMS external); 15N (CDCl3, C6D6,
2
2
1J (CCdO) ) 97.1 Hz, J (COCdO) ) 9.0 Hz, J (COCO) ) 8.9
Hz. 29Si NMR (C6D6): δ 7.44. 15N NMR (C6D6): δ -331
(1J (29Si-15N) ) 5.0 Hz, N(SiMe3)2), 102 (GeNdN), 184 (GeNdN).
MS (EI; 70 eV): m/ z (relative intensity) 537 (4) [M - Me+],
277 (100). Anal. Calcd for C17H42GeN4O4Si4 (551.48): C,
37.03; H, 7.68; N, 10.16. Found: C, 37.01; H, 7.76; N, 9.99.
Met h yl 2,2,7,7-Tet r a k is[b is(t r im et h ylsilyl)a m in o]-5-
m eth oxy-6-oxa -3,4-d ia za -2,7-d iger m a bicyclo[3.2.0]h ep t-
3-en e-1-ca r boxyla te (3). A solution of a 2.94 g (5.33 mmol)
(13) Allen, F. H.; Bellard, S.; Brice, M. D.; Cartwright, B. A.;
Doubleday, A.; Higgs, H.; Hummelink, I.; Hummelink-Peters, B. G.;
Kennard, O.; Motherwell, W. D. S.; Rodgers, J . R.; Watson, D. G. Acta
Crystallogr. 1979, B35, 2331.
(14) Rademacher, P. Strukturen organischer Moleku¨le; VCH: Wein-
heim, Germany, New York, 1987.

Reactions of Germylenes and Stannylenes
Organometallics, Vol. 15, No. 1, 1996 413
amount of 2 dissolved in 60 mL of hexane is heated with
stirring to 50 °C for 4 h. A 40 mL volume of the solvent is
evaporated under reduced pressure and the remaining solution
slowly evaporated at ambient temperature. Crystals of 3 thus
obtained were collected on a glass frit and washed twice with
5 mL of hexane at -78 °C. Dimethyl diazomalonate was
distilled from the remaining liquid at 35 °C/0.01 mbar and
identified by its MS and IR spectrum. 3 (yield 0.52 g, 0.55
mmol, 21%) forms colorless crystals: mp 149 °C; 1H NMR
(C6D6) δ 0.38 (s, 18 H), 0.40 (s, 9 H), 0.45 (s, 27 H), 0.49 (s, 9
H), 0.61 (br s, 9 H) (SiMe3), 3.37 (s, 3 H), 3.70 (s, 3 H) (OMe);
13C NMR (C6D6) δ 5.55 (3 C), 5.62 (3C), 6.81 (9 C), 6.93 (6 C),
7.52 (3 C) (SiMe3), 51.77, 52.29 (OMe), 115.02 (COMe), 164.83
(CdN), 172.70 (CdO); 29Si NMR (C6D6) δ 3.32, 5.38, 5.94 (2
Si), 6.58 (2 Si), 7.55, 9.07 (6 s); MS (EI; 70 eV) m/ z (relative
intensity) 929 (5) [M - Me+], 913 (3) [M - MeO+], 394 (36)
[{(Me3Si)2N}2Ge+], 379 (100) [{(Me3Si)2N}2Ge - Me+]. Anal.
Calcd for C29H78Ge2N6O4Si8 (944.84): C, 36.87; H, 8.32; N, 8.89.
Found: C, 36.81; H, 8.24; N, 9.04.
[{(Me3Si)2N}2Ge - Me+]. Anal. Calcd for C20H46GeN4O5Si4
(607.54): C, 39.54; H, 7.63; N, 9.22. Found: C, 39.48; H, 7.82;
N, 9.06.
2,2-Bis[bis(tr im eth ylsilyl)a m in o]in d en o[2,1-e]-1,3,4,2-
oxa d ia za ger m a n in -5(2H )-on e (7), Bis(1,1,1,3,3,3-h exa -
m eth yld isila za n a to-N){[in d a n e-1,2,3-tr ion e 2-({2,2-bis-
[bis(tr im eth ylsilyl)a m in o]-2,5-d ih yd r o-5-h yd r oxyin d en o-
[2,1-e]-1,3,4,2-oxa d ia za ger m a n in -5-yl}h yd r a za n a to)](2-
)-N,O1,O2}ger m an iu m (7)2, an d 2,2-Bis[bis(tr im eth ylsilyl)-
am in o]in den o[2,1-e]-1,3,4,2-oxadiazastan n in -5(2H)-on e (8).
To a stirred solution of bis[bis(trimethylsilyl)amino]germane-
(II) (6.38 g, 16.22 mmol) and -stannane(II) (4.63 g, 10.54
mmol), in 20 mL of toluene, the equivalent amount of 2-diazo-
1,3-indanedione (2.79 g for 7 and 1.81 g for 8) dissolved in 60
mL of toluene is added dropwise at ambient temperature. The
reaction mixture of 7 (and (7)2) is dark green, and that of 8 is
dark brown. Stirring is continued for 2 h. Crystallization is
achieved at -25 °C. 8 is obtained in the form of yellow crystals
by twice recrystallizing it from toluene: yield 3.60 g (54%);
decomposition at about 130 °C. Monomeric 7 was isolated in
the form of yellow-brown hexagonal crystals (decomposition
at about 170 °C) by slow evaporation of its solution in toluene
at ambient temperature. Its dimer (7)2 crystallized from very
diluted solutions in toluene at -25 °C in the form of green
needles (decomposition at 181-182 °C). When the yellow-
brown crystals of 7 are dissolved, a green solution results
again. The yield of 7 + (7)2 is 7.86 g (85%).
({Dim eth yl[ter t-bu tylcar bam oyl)h ydr azon o]m alon ato}-
(2-)-N′,O1,O2)bis(1,1,1,3,3,3-h exa m eth yld isila za n a to-N)-
ger m a n iu m (4), ({Dim et h yl[(h yd r oxyp h en ylm et h yl)-
h y d r a z o n o ]m a lo n a t o }(2-)-N ′,O 1 ,O 2 )b i s (1,1,1,3,3,3-
h exa m et h yld isila za n a t o-N)ger m a n iu m (5), a n d ({Di-
m e t h y l[3-h y d r o x y a lly l)h y d r a z o n o ]m a lo n a t o }(2-)-
N′,O1,O2)b is(1,1,1,3,3,3-h exa m et h yld isila za n a t o-N)ger -
m a n iu m (6). To the solution (showing a red color) of 2 in 60
mL of hexane, the corresponding reagent is added in slight
excess with a syringe through a septum at ambient temper-
ature. For 4, to 3.60 g (6.53 mmol) of 2 is added 0.7 g (7.1
mmol) of tert-butyl isocyanate. For 5, to 3.36 g (6.09 mmol) of
2 is added 0.8 g (7.5 mmol) of benzaldehyde. For 6, to 2.32 g
(4.21 mmol) of 2 is added 0.25 g (4.5 mmol) of acrolein. The
solutions immediately change their color to yellow. 4 and 5
crystallize upon storing at -25 °C, and 6 crystallizes at -80
°C. Single crystals of 4 were grown at 0 °C from a solution in
hexane saturated at 50 °C. 4: yield 3.34 g (5.13 mmol), 79%;
yellow crystals; mp 99 °C. 5: yield 2.43 g (3.70 mmol), 61%;
bright yellow crystals; mp 80 °C. 6: yield 1.75 g (2.88 mmol),
68%; bright yellow crystals; mp 94 °C.
4. 1H NMR (CDCl3): δ 0.21 (s, 36 H, SiMe3), 1.30 (s, 9 H,
CMe3), 3.74, 3.96 (2 s, 2 × 3 H, OMe). 13C NMR (CDCl3): δ
4.98 (SiMe3), 30.32 (CMe3), 52.25 (CMe3), 52.19, 53.98 (OMe),
117.96 (NNdC), 148.59 (t-BuNdC), 162.85, 165.21 (CdO). MS
(EI; 70 eV): m/ z (relative intensity) 493 (1) [M - N2C-
(COOMe)2+], 379 (74) [M - N2C(COOMe)2 - Me3CNCO -
Me+], 275 (100) [Me5Si2N - NSi2Me4+]. FI: m/z 394 (16)
[{(Me3Si)2N}2Ge+], 158 (100) [N2C(COOMe)2+], 84 (66) [Me2-
CNCO+]. Anal. Calcd for C22H51GeN5O5Si4 (650.61): C, 40.61;
H, 7.90; N, 10.76. Found: C, 40.44; H, 8.10; N, 10.35.
7. 1H NMR (CDCl3, 50 °C): δ 0.24 (s, 36 H, SiMe3), 7.65-
7.73 (m, 2 H), 7.73-7.81 (m, 1 H), 7.83-7.88 (m, 1 H) (C6H4).
13C NMR (CDCl3, 50 °C): δ 4.86 (SiMe3), 121.83, 122.53,
128.94, 130.48, 134.03, 134.83, 136.25, 166.03, 188.37 (CdO).
29Si NMR (CDCl3, 50 °C): δ 8.06. MS (EI; 70 eV): m/ z
(relative intensity) 566 (3) [M+], 523 (4) [M - Me - N2+], 379
(80) [{(Me3Si)2N}2Ge -Me+], 275 (100) [Me5Si2N2Si2Me4+], 172
(64) [N2O2C3C6H4+]. Anal. Calcd for 7 C21H40GeN4O2Si4
(565.51): C, 44.60; H, 7.13; N, 9.91. Found: C, 44.66; H, 7.24;
N, 9.80.
(7)2. 1H NMR (CDCl3): δ 0.17 (br, s), 0.20 (s), 0.29 (s), 0.31
(br, s) (72 H, SiMe3), 7.36-7.77 (6 m, 8 H, C6H4). 13C NMR
(CDCl3): δ 5.06, 5.18, 5.36 (br), 5.99 (br, SiMe3), 104.48, 116.97,
122.14, 122.47, 123.01, 126.16, 129.96, 131.03, 133.21, 133.66
(br), 134.38, 134.81, 137.40, 138.96, 142.68 (br), 148.59, 179.11,
186.34 (CdO). 29Si NMR (CDCl3): δ 5.89 (br), 6.11 (br), 6.85,
7.25. 15N NMR (CDCl3): δ -332.2, -330.7, -328.6, -328.5
(N(SiMe3)2), -61.4 (N(7)), 19.4 (N(8)), 163.6 (N(6)), 191.1 (N(5))
(assignments tentative). MS (EI; 70 eV): m/ z (relative
intensity) 1102 (1) [M - N2+], 958(6) [M - N2C3O4C6H4+], 566
(4) [M/2+], 146 (100) [Me6Si2+]. Found for C42H80Ge2N8O4Si8
(1131.01): C, 43.07; H, 7.25; N, 9.93.
8. 1H NMR (CDCl3): δ -0.03 (br s, 18 H) (SiMe3), 7.37-
7.45 (m, 2 H, 3-H, 4-H), 7.50-7.56 (m, 1 H), 7.64-7.70 (m, 1
H) (2-H + 5-H). 13C NMR (CDCl3): δ 5.80 (3J SnC ) 13.2 Hz),
6.36 (3J SnC ) 16.0 Hz, SiMe3), 98.80 (3J SnC ) 28.5 Hz, C-8),
121.63 (C-4), 126.88 (C-3), 128.55 (2J SnC ) 29.4 Hz, C-7), 129.12
(C-5), 132.46 (C-2), 134.98 (3J Sn ) 16.1 Hz, C-6), 148.79 (4J SnC
) 8 Hz, C-1), 176.69 (4J SnC ) 16.7 Hz, C-9). 29Si NMR: δ 6.81
(s), 7.39 (s). 119Sn NMR (toluene-d8): δ -309.1. MS (EI; 70
eV): m/ z (relative intensity) 440 (2) [M - N2C3O2C6H4+], 130
(100) [Me4Si2N+]. MS (FD): m/ z (relative intensity) 440 (4),
172 (100) [N2C3O2C6H4+]. Molecular mass (cryoscopic method
in C6H6), found: 615. Anal. Calcd for C21H40N4O2Si4Sn
(611.6): C, 41.24; H, 6.59; N, 9.16. Found: C, 41.16; H, 6.35;
N, 8.86.
In d a n e-1,2,3-tr ion e 2-({Bis[bis(tr im eth ylsilyl)a m in o]-
h yd r oxyger m yl}h yd r a zon e) (9). Water (0.054 g, 3 mmol)
is added to the stirred solution of 1.56 g (2.76 mmol) of (7)2 in
20 mL of toluene which causes the green solution to change
its color to brown. After evaporation of the solvent in vacuo,
the residue is recrystallized from toluene and crystals are
collected at -25 °C. The yield is 0.83 g (1.42 mmol, 52%) of a
bright yellow solid (decomposition at 182 °C). 1H-NMR
(CDCl3): δ 5.06 (s, 36 H, SiMe3), 2.63 (s, 1 H, O-H), 7.72-7.79
5. 1H NMR (CDCl3): δ 0.17 (br s, 36 H, SiMe3), 3.80, 4.08
(2 s, each 3 H, OMe), 6.16 (s, 1H, CHO), 7.31-7.37 (m, 2H),
7.69-7.75 (m, 2 H), 7.81-7.85 (m, 1 H) (C6H5). 13C NMR
(CDCl3): δ 4.83 (SiMe3), 51.02, 54.88 (OMe), 94.45 (CHO),
103.23 (CdN), 126.82 (C-3,5), 127.74 (C-4), 128.03 (C-2,6),
139.71 (C-1) (C6H5), 160.70, 171.36 (CdO). 29Si NMR
(CDCl3): δ 5.1 (br s). MS (EI; 70 eV): m/ z (relative intensity)
395 (12) ([Me3Si)2N]2Ge + H+), 73 (100) (SiMe3+). FI: m/z 394
(8) [{(Me3Si)2N}2Ge+], 158 (39) [N2C(COOMe)2+], 106 (100)
[PhCHO+]. Anal. Calcd for C24H48GeN4O5Si4 (657.60): C,
43.84; H, 7.36; N, 8.52. Found: C, 48.11; H, 7.65; N, 8.29.
6. 1H NMR (CDCl3): δ 0.12 (br s, 36 H, SiMe3), 3.76, 4.05
3
2
(2 s, each 3 H, OMe), 5.32 (dt, J HH ) 10.4 Hz, J HH(gem)
≈
4J HH(allyl) ) 1.5 Hz, 1 H, CHdCHCH2), 5.60 (dt, J HH ) 17.2
3
2
4
Hz, J HH(gem) ≈ J HH(allyl) ) 1.4 Hz, 1 H, CHdCHCH2), 5.66 (br
d, 1 H), 6.04 (br ddd, 1 H) (2 × CHdCH). 13C NMR (CDCl3):
δ 5.04 (SiMe3), 51.27, 55.11 (OMe), 95.76 (CHdCHCH2), 103.16
(CdN), 118.47 (CHdCHCH2), 135.96 (CHdCHCH2), 160.92,
171.44 (CdO). MS (EI; 70 eV): m/ z (relative intensity) 608
(7) [M+], 593 (5) [M - Me+], 549 (10) [M - COOMe+], 379 (100)

414 Organometallics, Vol. 15, No. 1, 1996
Ta ble 2. Cr ysta l Da ta a n d Str u ctu r e Refin em en t Deta ils for 1-4 a n d (7)2
Ossig et al.
1‚1/2C6H14
2
3
4‚1/2C6H14
(7)2‚4C4H8O
formula
Mr
C38H65GeN4O4Si2
770.71
triclinic
P1h
1090.86(7)
1134.56(9)
1748.9(2)
84.184(5)
77.088(5)
83.684(5)
2.0904(4)
2
C17H42GeN4O4Si4
551.50
monoclinic
P21/c
1334.5(1)
1434.8(1)
1520.4(2)
90
101.21(1)
90
2.8556(5)
4
C29H78Ge2N6O4Si8
944.87
triclinic
P1h
1161.0(4)
1231.5(4)
1850.6(7)
102.76(2)
92.67(2)
107.23(2)
2.447(2)
2
C25H58GeN5O5Si4
693.71
monoclinic
C2/c
3466.4(4)
1240.3(2)
1814.9(2)
90
103.07(2)
90
7.601(2)
8
1.212
0.969
2968
C58H112Ge2N8O8Si8
1419.46
triclinic
P1h
1348.2(5)
1553.4(5)
2029.5(7)
106.38(2)
106.71(2)
99.45(2)
3.764(2)
2
cryst syst
space group
a (pm)
b (pm)
c (pm)
R (deg)
â (deg)
γ (deg)
V (nm3)
Z
Dx (Mg/m3)
1.224
0.831
826
1.283
1.268
1168
1.282
1.461
1004
1.252
0.977
1512
µ (mm-1
F(000)
)
cryst size (mm)
2θ range (deg)
range of hkl
0.5 × 0.4 × 0.3
0.4 × 0.2 × 0.2
0.3 × 0.3 × 0.2
0.7 × 0.5 × 0.5
0.4 × 0.3 × 0.2
8-50
8-45
8-45
8-45
8-45
-12 e h e 13
-13 e k e 13
-13 e l e 20
7814
7422
0.0520
-14 e h e 14
-15 e k e 15
-16 e l e 16
14 811
3717
-12 e h e 12
-13 e k e 12
-17 e l e 19
7281
6373
0.0357
-36 e h e 37
-13 e k e 12
-19 e l e 19
12 369
4948
0.0309
-14 e h e 14
-16 e k e 16
-11 e l e 21
10 321
9775
0.0621
no. of rflns coll
no. of indep rflns
R(int)
0.0373
0.749
Tmin
0.599
0.773
0.561
Tmax
0.675
0.805
0.847
0.929
no. of data
no. of params
no. of restraints
S
R1 [I > 2σ(I)]
wR2 (all data)
g1
7418
459
0
1.049
0.0355
0.0924
0.0354
1.5354
0.392
-0.453
3716
285
0
6364
468
0
1.061
0.0310
0.0736
0.0261
3.1706
0.364
-0.404
4947
487
307
1.048
0.0318
0.0866
0.0355
22.7641
0.814
-0.287
9764
950
1306
1.030
0.0548
0.1541
0.0486
6.8781
1.032
0.0251
0.0539
0.0169
2.4782
0.261
g2
largest diff peak
0.576
-0.339
largest diff hole (e nm-3
)
-0.193
(m, 3-H + 4-H, 2 H), 7.83-7.87 (m, 1 H), 7.90-7.94 (m, 1 H)
(2-H + 5-H) (C6H4), 11.78 (s, 1 H, N-H). 13C NMR (CDCl3): δ
5.06 (SiMe3), 122.85, 123.08 (C-3, C-4, C6H4), 134.15 (CdN),
134.71, 135.02 (C-2, C-5, C6H4), 138.85, 140.24 (C-1, C-6, C6H4),
186.40, 188.11 (CdO). 29Si NMR (CDCl3): δ 6.78 (s). MS (EI;
70 eV): m/ z (relative intensity) 569 (28) [M - Me+], 277 (100).
Anal. Calcd for C21H42GeN4O3Si4 (583.52): C, 43.23; H, 7.25;
N, 9.60. Found: C, 43.01; H, 7.42; N, 9.41.
The hexane molecule in structure 1 is ordered on the
inversions center, while the hexane in structure 4 is disordered
on the 2-fold axis. It was refined with distance restraints and
similarity and rigid bond restraints for the anisotropic dis-
placement parameters. Antibumping restraints were used,
because there were short distances between the hexane and
the disordered COOMe group. In structure (7)2 there are four
THF molecules, of which two are ordered while two are
disordered. They were refined as five-membered carbon rings
in two and three positions, respectively (occupancies 0.85:0.15
and 0.4:0.4:0.2). Again distance restraints and similarity and
rigid bond restraints were used.
Su m m a r y. In the reactions between diazagermylenes and
diazastannylenes with diazo compounds carrying non-enoliz-
able substituents, formation of primary and secondary reaction
products depends critically on the metal and the substituents.
In some cases equilibria between educts and products or
between different products can be observed. In none of the
systems studied here could formation of a free germaimine
species be substantiated, which does not exclude short-lived
germaimine intermediates.
X-r a y Str u ctu r e Deter m in a tion s for 1-4 a n d (7)2. Data
were collected at -120 °C on a Stoe-Siemens diffractometer
with monochromated Mo KR radiation (λ ) 71.073 pm).
A
semiempirical absorption correction was employed for struc-
tures 1-3, and an empirical correction was employed for
structure (7)2. The structures were solved by direct methods
using SHELXS-90.15 All non-hydrogen atoms were refined
anisotropically. For the hydrogen atoms the riding model was
used. The structures were refined against F2 with a weighting
scheme of w-1 ) σ2(Fo2) + (g1P)2 + g2P with P ) (Fo2+ 2Fc2)/3
using SHELXL-93.16 The R values are defined as R1 ) Σ||Fo|
4
- |Fc||/Σ|Fo| and wR2 ) [Σw(Fo2 - Fc2)2/ΣwFo
]
0.5. Figures 1-5
(hydrogen atoms omitted) show 50% probability displacement
ellipsoids. Crystal data and structure refinement details are
listed in Table 2.
Ack n ow led gm en t. Support of this work by the
Fonds der Chemischen Industrie is gratefully acknowl-
edged.
In structure 4 one COOMe group is disordered over two
positions with occupancies of 0.5. Distance restraints were
used for the refinement. In structure (7)2 one SiMe3 group is
disordered over two positions with occupancies of 0.6 and 0.4.
Again distance restraints and also similarity and rigid bond
restraints for the anisotropic displacement parameters were
used.
Su p p or tin g In for m a tion Ava ila ble: Tables of crystal
data, complete fractional coordinates and U values, bond
lengths and angles, and anisotropic displacement parameters
and fully labeled figures of 50% anisotropic displacement
parameters of the structures 1-4 and (7)2 (32 pages). Order-
ing information is given on any current masthead page.
(15) Sheldrick, G. M. Acta Crystallogr., Sect. A 1990, 46, 467.
(16) Sheldrick, G. M. SHELXL-93, program for crystal structure
refinement, University of Go¨ttingen, 1993.
OM950599P