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Constitutional and Configurational Stability of a Carbamoyl-Tetracarbonyliron Anion Complex.

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gous nitrogen and sulfur compounds. This applies particularly
to phosphorus(v) heterocycles, since only two compounds
have so far been isolated for which a phosphorus(v) three-membered ring structure has been postulated['". Ibl. In contrast,
phosphorus(v) three-membered ring structures have frequently
been assumed as reactive intermediates. and actually detected
in some cascs~"! We now report the isolation and structural
proof of a diazaphosphiridine 3-oxide and a simple phosphonic
ester hydrazide synthesis.
The phosphonic diamides ( I ) , which are readily accessible
from phosphonic dichlorides and primary amines in acetonitrile, are smoothly converted into the stable crystalline Nchloro amides (2) by terr-butyl hypochlorite. Treatment of
(2) with alkoxides in anhydrous T H F affords the phosphonic
ester hydrazides ( 4 ) in good yields. The N-N bond in ( 4 )
was established in the case of ( 4 c ) , R3=(CH3)3C,by degradation with conc. hydrochloric acid to 1,2-di-rert-butylhydrazine,
which was isolated as the perchlorate and as the 2,4,6-trinitrobenzenesulfonate.
plex decomposition yielding, infer a h , 2-methylpropene, only
begins at 140°C. A fragment C4H,0P corresponding to a
cheletropic decomposition could not be detected in the high
resolution mass spectrum.
1,2,3-Tri-tert-buf~ldiuzuphosphiridinr3-oxide ( 3 c)
rerr-Butylphosphonic dichloride (0.2 mol) wits heated to
150°C with rert-butylamine (1.3 mol) in acetonitrile (135 ml)
for 24h. Yield: 97% of (1 c), m.p. 181--182°C (from ligroin).
Compound ( l c ) (0.1mol) and rrrt-butyl hypochlorite
(0.12mol) were reacted in CCI4 at 0-20°C to give ( 2 c ) ,
m. p. 110-1 11 "C, 95 %
' , yield. A cooled solution of potassium
3-rert-butyl-2,2-dimethyl-3-heneicosanolate( 10.5 mmol) in
T H F (25ml) was added to a solution of ( 2 0 (10mmol) in
T H F (100 ml) at - 30°C under argon and with rigorous exclusion of moisture. The mixture was allowed to warm to - 5 "C
during 2h. after which the solvent was distilled off at
torr. The residue was then sublimed at 35"C/6x
torr
onto a cold finger at -30°C; yield after resublimation 1.46g
(59
of ( 3 c), colorless crystals, m. p. 63.5-65 "C.
'x>)
Received: March 27. 1975 [ Z 229 IE]
German version: Angew. Chem. X 7 . 487 11975)
CAS Registry numbers:
1 11.). 55702-27-7: (21.). 55702-28-8: (31.). 55702-29-9:
rrrr-butylphosphonic dichloride. 4707-95-3: rwr-butylamine. 75-64-9
[ l ] a ) K.-D.Gimfwimiitii and A . G~inttinq.Cheni. Ber. 10'. 3023 llY6Y): E
W K o o s . J. P. Kindn. Kooi. E. E . G r t w . and J. K . Stilk,. J. C . S.
Cheni. Comm. 1Y72. 1085. b) Note i i i f d i ~ r li i t p w o / IJune 27. 1975):
Recently a )i5-phosphirane and a 1.2h'-azaphosphiridine have been
obtained: E . N i d r and W F1ii.A. Angew. Chem. 87. 355 (1975):
Angew. Chem. internat. Edit. 14. 363 (1975). c) P. B ~ ~ r i i G.
s . Ciipoz:i,
and P. HurrAr. Tetrahedron Lett. 1Y72. 975: D. B. D i w t ~and L. S. Shili.
J . Am. Chem. SOC. Y6, 317 (1974)
[2] The base was !ailor-made for this purpose. The alcohol was prepared
4-tetrdmethylpentanOne [ 3 ] (yield 74",,. b.p. I 5 to
142"C/8x lo-'' torr. m.p. 34-35"C. from hexane) and reacted with
KH in T H F [4].
[3] P. J. P r a r w . D. H . Richor(/\. and N . F. S d I I . J. C. S. Perkin I IY72.
Isolation of the diazaphosphoridine oxide ( 3 c ) can be
accomplished by sublimation at
torr if the potassium
salt of the non-nucleophilic, almost nonvolatile 3-trrt-butyl2,2-dirnethyl-3-henei~osanoI[~1
is used as base under rigorous
exclusion of moisture. ( 3 c ) forms colorless. extremely hygroscopic crystals which can be recrystallized from a small
volume of n-hexane at - 78 "C.
Elemental analysis and the high resolution mass spectrum
indicated the expected molecular formula. The IR and NMR
spectra as well as the reaction with methanol prove structure
(3c); IR (CCI4): no NH, no O H ; 1266, 1198 c m - ' (tBu,
P=O); 'H-NMR (90MHz, [D,]toluene): 6 = 1.21 d, 4JH.p
=
0.4 Hz, 2 tBu); 1.23 ppm (d, 3JH-p=
17.9 Hz, tBu). The 'HNMR spectrum is temperature dependent and on cooling of
the sample it exhibits broadening and splitting ofthe N-terr-butyl doublet : T, = - 38 "C, Ac( - 73 "C)= 27.3 Hz. Determination
of the two long-range coupling constants at low temperature
was unsuccessful owing to viscosity broadening of the signals.
The low inversion barrierrs1 (AGZ = 1 1.7 kcal mol I ) is certainly attributable in part to steric interaction of the cis-ferrbutyl groups in the ground state. ,'P-NMR (40.5 MHz.
[D,]toluene): 6,= -2.35 ppm16].The upfield shift of the 3'PNMR signell of (3c) relative to that of f l c ) [S,= - 32.62 ppm
(CDCI,)] and of ( 2 0 [6,= -40.10 ppm (CDCI,)] indicates
the special kind of bonding in the three-membered ring['].
Further support for the structure ( 3 c ) comes from the
immediate reaction with methanol, which quantitatively
affords ( 4 c ) , R3=CH3, already obtained directly from ( 2 c ) .
(3c) remains unchanged after 20 h at 90°C in benzene. Com-
1655.
[4] C. A . 5roa.n. J. Org. Chem. 39. 3913 (1974).
[ 5 ] J. M. Lrhn. Fortschr. Chem. Forsch. 15. 31 I (1970): J. 5. Lufithrrr,
Top. Stereochem. 6 , 19 (1971).
161 o p i 0 indicates a downfield shift relative to X5",, phosphoric acid.
[7] S. Chau. H . Go1i1irhifu.H . Kerzcr. D. G. Rou..w//.and R. 7illlg. Tetrahedron
25. 1097 (1969).
Constitutional and Configurational Stability of a Carbamoyl-Tetracarbonyliron Anion Complex['](**]
By Johannrs Schrnerzer, Jijrg Daub, and Peter Fisc.hrr[']
Acyl derivatives of transition metals may be synthesized
from the corresponding carbonyl complexes with organoalkali
metal compoundsI2] as well as with aluminum and titanium
amidesI3,1' . With hexamethylmethanetriamine ( I ). we have
now found another amide donor capable of transferring the
N(CH ,)* moiety to transition metal carbonyl complexes.
Reaction of ( I ) with Fe(CO), in a 1 : I 0 molar ratio
affords a red oil (947; yield), sparingly soluble in apolar
solvents and having the elementary composition
[C,H,FeNO,] [C,H ,N2]. Alkylation yielding the known
[*] Dip].-Chem. I. Schmetzer and Prof. Dr. I. Daub
Chemisches lnstitut der Universitiit
X4 Regenshurg. Uiiiversitlitsstrasse 31 (Germany)
Dr. P. Fischer
Institiit f u r Organische Chemie der Universitii!
7 Stuttgart 80. Pfaffenwaldring 55 (Germany)
[**I
This work was supported by the Deutsche Forschungs~emeinschaft
and the Fonds der Chemischen Industrie.
487
carbene complex 3 )I5' and spectroscopic evidence indicated
structure (2) for this oil.
The I3C-NMR data for the amidinium moiety of (2) are
in close agreement, regarding both chemical shift and coupling
constants, with those of tetramethylformamidinium methylsulfate ( 4 ) (Table 1). The resonance of the carbamoyl carbon
f H 3
Fe(C0)5/(I ) since hexamethylmethanetriamine ( I ) can be
extracted from the oil (2) with benzene. As shown by the
well-resolved 3J coupling between N-C3.4H3protons and Cz,
the rate of equilibration is fairly slow at room temperature;
furthermore, the equilibrium must lie far on the side of the
complex (2) because signals of ( I ) (see Table 1) cannot be
detected in either the 'H- or the I3C-NMR spectrum. This
extreme displacement of the equilibrium in favor of the carbamoyl complex-as compared with the Fe(CO),/amine sy~tem[~'--has to be accounted for in terms of the high amidinium cation stability['!
Different activation barriers are found for the coalescence
of the dimethylamino signals in the amidinium and carbamoyl
part of (2), the values from 'H- and I3C-NMR spectra, however, being comparable in each case (Table 2). This shows
that the dynamic process responsible is indeed rotation of
the N(CH3)z groups about the C2-N and C5-N bond,
respectively, for an amide exchange in the sense of the equilibrium discussed above would result in equilibration of all
N-methyl protons.
The C-0 stretching vibrations are displaced to increasingly
lower wave numbers along the series (6) + ( 5 ) + (2), corresponding to a decrease in C-0 bond strength (Table 1);
for the carbonyl 13C resonance, there is a concomitant downfield shift[']. Hence a distinctive gradation of ligand acceptor
strength appears for the carbonyl iron complexes (CO),FeL :
Table 1 . "C-NMR and IR spetroscopic data of rhe carbonyliron complexes (21. ( 5 ) . and ( 6 ) . of the compounds ( I ) and (4). and of Fe(CO),
C-l
C-2
1R [cm-
101.66
41.46
157.65
C-1
{
c-2,3
39'43
46. I7
'3
c-1
c-2
c-3.4
C-5
C-6.7
VC.(>
(THF)
221.10
206.01
38
156.98
39.08
45.79
-
2020
1947
1928
1890
c-l
C-2
(hexane)
217.4 [8]
2 13.2
C-l
c-2
215.33 [ I ]
251.19
2044[9]
1963
1938
vcG0
(KBr.
high
pressure)
2060
1979
1956
1937
209.6
C-l
(neat)
2022
2000
VYGO
[a] Relative to TMS as internal standard, 3 0 ° C in CD,CN.
Received: April 8. 1975:
C2, on the other hand, is split into a heptuplet by long-range
in abridged form: April 21, 1975 [Z 232 IE]
coupling to the six N-methyl protons ( 3 J ~ , ~ - ~ - p = 3Hz),
.3
German version: Angew. Chem. 87, 41(9(1975)
thus providing direct evidence for the N(CH3)2 group being
covalently bonded to one of the carbonyl functions. At 40°C
two N-CH3 signals in a 6: 12 intensity ratio appear in the
CAS Registry numbers:
'H-NMR 'pectrurn whi*'
lowering the temprature'
Fe(CO),. 13463-40-6; ( 1 5762-56-1 ; ( 2 ) . 55658-17-8
are successively resolved into two singlets each (Table 2).
( 4 ) , 2013-91-4: ( 5 J , 41755-21-9; ( 6 , . 54854-43-2
J.
Table 2. 'H-NMR data
[a, ppm] of the complex ( 2 ) [a].
-20°C
5-H
3-H
4-H
6-H
7-H
6.39
( I H)
::::} :iz;
2.70
2.33
(6H)
+40T
r,
AG?
["CI
[kcal/mol]
H)
6.56
(I
2.99
(6H)
+ 7
13.7
2.70
(12H)
140
15.3
[a] 100 MHz, in CD,CN.
These findings provide unequivocal proof of the ionic structure ( 2 ) . At the same time, though, a dynamic equilibrium
must exist between the carbamoyl complex (2) and
488
~
[ I 1 J . Douh and J . Koppler. J. Organometal. Chem. 81. C 5 (1974).
E . 0. Fischrr, Angew. Chem. 86. 651 (1974).
[31 a ) W Pet; and G . Srhmid. Angew. Chem. 84. 997 (1972): Angew. Chem.
internat. Edit. I / . 934 (1972): b) W P r f i . J. Organometal. Chem. 72.
369 ( 1974).
r41 R . J . Angulki, Accounts Chem. Res. 5, 335 (1972).
[51 E . 0. Fisrhrr. H . J . Beck, C . G. K r r i f r r , J . Lynch. J . Miillrr. and E.
Winklrr, Chem. Ber. 105. 162 (1972).
C61 W Betz and J . Douh, Chem. Ber. 107. 2095 (1974).
c71 See also G . M. Bodnrr and L . J . Todd, Inorg. Chem. 13. 1335 (1974).
C83 D. J . Cardin. B. Crfinkoyo. E. Crrinkuja. M. F. Lopprrf. E. W Rondall.
and E. Rosrnhrrq. J. C . S. Dalton 1973, 1982.
[91 B. Curinkow. P. Dixnruf. and M . F. Lupprrf. J. C. S . Dalton 1974.
1827.
PI
Angrw. Chrm. infrrnof. Edif. 1 Vol. 14 ( 1 9 7 5 ) No. 7
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