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Kinetic and Thermodynamic Control in the Reaction of (Ph3P)2Pto2 with (E)-2-Butenal.

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r e l a t e d compounds 14.61 and has f r e q u e n t l y been suggested as an
This manuscript is
Dieses Manuskript ist
zu zitieren als
Angew. Chem. Suppl.
7983,l-9
i n t e r m e d i a t e i n t h e palladium.
to b e cited as
Angew. Chem. Suppl.
7983,l-9
i r i d i u m and rhodium-complex
catalysed
o x i d a t i o n o f t e r m i n a l o l e f i n s t o methyl ketones by oxygen o r a l k y l
hydroperoxides 171.
0 Verlag Chernie GrnbH. D-6940Weinhem, 1983
The mechanism by u h i c h complex
w i t h t h e h e l p of 4-[2H31but-2-enal.
1.3 f i ( t h i o m e t h y 1 ) a l l y l
4
rearranges was e s t a b l i s h e d
prepared by a l k y l a t i o n of
l i t h i u m 181 w i t h 12H31-methyl methanesulphonate
followed by d e s u l p h u r i s a t i o n w i t h HgC12 i n aqueous t e t r a h y d r o f u r a n .
Samples o f complex
4-
i n t h e presence of e x c e s s 4-1‘Hl
CD2C12,and o f deuterated
4- t o g e t h e r
-but-2-enal
w i t h excess but-?-ma1
i n CD C l
2 2
Kinetic and Thermodynamic C o n t r o l In the ReactLon of
were h e l d a t 40’
( P hP )_
PtO
-
p a r a l l e l Puns Yere c a r r i e d Out i n CH2C12 and monitored by ‘H
with
(E1-2-Butenal
and t h e ‘ H NMR s p e c t r a monitored
r e s u l t s demonstrate t h a t i s o t o p i c exchange i n
John M . Brown and Robert A.
IMichael J. Broadhurst,
John
5
in
at intervals.
Some
NMR.
The
competes u i t h rearrangement.
Three models were t e s t e d b y k i n e t i c s i m u l a t i o n 191, namely ( a ) i n t r a m o l e c u l a r
rearrangement. w i t h competing exchange i n e i t h e r s t a r t i n g m a t e r i a l or
S e l e c t i v e o x i d a t i o n o f a l e f i n s by t r a n s i t i o n - m e t a l complexes and
co-oxidants
product.
The i s o l a t i o n
i s a s u b j e c t o f keen c u r r e n t i n t e r e s t 111.
(b) r e v e r s i o n t o dioxygen complex and recombination v i t h i s o t o p i c a l l y
pooled aldehyde. f a v o u r i n g
2at
-
e q u i l i b r i u m o r ( c ) d i r e c t displacement o f
and chemical p r o p e r t i e s o f p o t e n t i a l i n t e r m e d i a t e s p r o v i d e s i n s i g h t
one aldehyde moiety by another. perhaps yia a ring-opened peroxycomplex
i n t o p o s s i b l e mechanisms.
O n l y t h e Last-named
i s c o n s i s t e n t w i t h observed r e s u l t s , and f i t s t h e
mechanism shown i n Figure 1; t h e most p e r t i n e n t a s s a y s are d i s p l a y e d i n
Figure 2.
Dr. Michael J. Broadhurst.
Ueluyn
D r . John
I n a l l runs, product
exchange than s t a r t i n g m a t e r i a l .
Roche Products P.1.c.
Garden C i t y . Herts. AL7 3AY. U.K
2- shows
a h i g h e r degree of i s o t o p i c
and c o n t r o l experiments demonstrate
t h a t i s o l a t e d product undergoes very slow exchange.
M. Brown,+ D r . Robert A. John.
Path (b) v i t h
reasonable r a t e constants f o r p a r t i t i o n i n g dioxygen complex
Dyson P e r r i n s Laboratory.
South Parks Road. OXFORD OX1 3 Q Y .
+
k i n e t i c a l l y favoured. f a i l s t o s i m u l a t e t h e d a t a .
To r e c e i v e correspondence
- 1 -
I t i s well-established
1 betveen
-
the two p o s s i b l e adducts so t h a t a t t a c k a t t h e carbonyl carbon i s
- 3 -
t h a t dioxygen
& triphenylphosphine
platinum
1 reacts
212.31.
-
With h i g h l y e l e c t r o p h i l i c o l e f i n s r e l a t e d cycloadducts
w i t h carbonyl compounds t o produce cycloadducts
2
are formed 141 and i n one case 151 a cycloadduct r e q u i r i n g 0-0 bond
cleavage I S produced.
In accord w i t h t h i s we f i n d t h a t complex
r e a c t s u i t h excess =-but-?-enal
t o form adduct 4Um.p.
-
300 MHz) 7.4 (brm. 30H. a r ) 5.65
‘ H NMR ( C D C L 3 .
130’
1
(dec)
(m.2H.Hb.HC)
Figure 1
5.40 (d. 1H. Ha. Jab
31P
=
4 Hz) 1.60 (d. 3H,Hd.
NMR (CH2C12) 13.7 (d. w i t h 195Pt
Jpp = 16 Hz) 10.9 (d. w i t h 195Pt
s a t e l l i t e s . Jptp
satellites.
k
P r e f e r r e d mechanism f o r t h e rearrangement o f complex
Jcd = 3 Hz) p.p.m.,
= 3567 Hz.
Jptp = 3353 Hz. J p p = 16 Hz))
The product proved l a b i l e i n s o l u t i o n i n t h e presence o f an excess o f
~
trans-but-2-enal
and an a n a l y t i c a l l y pure rearrangement product could
be i s o l a t e d a f t e r s e v e r a l days s t a n d i n g i n CH C l o r C7H8.
2 2
Structure
5 f o l l o w s from i t s spectroscopic p r o p e r t i e s p a r t i c u l a r l y NMR. ((m.p.
‘ H NMR ( C D C L 3 .
300 MHz) 9.0
3.6 (m. IH. Hc; J
cd
Jp,b = 12 Hr. 3 H r ;
CHZC12) 23.3
(d. 1H. Ha;
= 6 Hz. Jbc = 3 Hz, J p , ,
Jpt,b
= 79 Hz) 1.3
(d. w i t h 19’Pt
10.6 (d. u i t h 19’Pt
pentane S t r u c t u r e o f
Jab = 3 H A 7.4 (brm.
(d.
s a t e l l i t e s , Jptpl
S
1 Hz) 3.1
3H. Hd)
precedent
(dec).
1H. Hb,
31P NMR
= 2400 Hz. Jpp = 16 Hz)
s a t e l l i t e s . JptpZ = 3320 HzD.
> finds
(m.
P.P.~;
145’
30H. A r )
The metalladioxacyclo-
i n t h e p l a t i n u m complex
time
6 and
-
Figure 2
1
3
-
Rearrangement o f i - d 3 c a r r i e d o u t a t 40’
i n CD C l i n t h e
2 2
presence o f a 10-molar excess o f but-2-enal.
Lines a. b. and c
are computer drawn c a l c u l a t i o n s of % r e a c t i o n . % exchange i n
4-d3 and % exchange i n z-d3 r e s p e c t i v e l y .
=,*
experimental p o i n t s taken a f t e r 3. 6 and 8.5 h.
and
are
The netailadioxapentane moiety ~n complex 5 proved q u i t e robust.
b e i n g i n e r t t o several reagents (excess PPh3. 4-Me NC H N. H2)
2 6 4
t o have o x o p h i l i c p r o p e r t i e s .
With r - b u t y l s n i t r i l e .
7
exchanged a t room temperature g i v i n g complex -
-
6 9.54
(d. l H , H a .
3.84 (m.
1H. Hb; Jpt,b
14.9
(CH2CL2)
31P
M . S (m/z.
(5,
= 88 H L )
one phosphine i s
(( ' H NMR (CD2C12)
15 H.Ar)
Jab = 4 H r ) 7.25 (m.
anticipated
4.15
(m.
F i e l d Desorption) 642/3/4/6;
1.r.
(KBr)
model f o r homogeneous c a t a l y s i s .
Examples o f e p o x i d a t i o n i n v o l v i n g
molecular oxygen are r a r e Ill/and t h e p u t a t i v e metallodioxacyclo-
1H. H c )
pentanes i n v o l v e d i n rhodium and palladium catalysed o x i d a t i o n s a r e
1.4 (d. 3H. HdJcd = 6H) 1.1 (s.9H.8ut)ppm;
w i t h 195-Pt s a t e l l i t e s . Jp,pt
i n t o __
t~an~-l-fo~myl-2-mefhyloxirane
ConYerSion of m - b u t - Z - e n a l
by molecular oxygen promoted by p l a t i n u m [ol complexes. serves as a
considered t o fragment t o methyl ketones by 6-hydrogen
l a b i l i s a t i o n /?/
= 2240 H r ) ppm;
2182 s. 1660 s crn-'.
A d d i t i o n of c h e l a t i n g phosphines caused displacement of b o t h PPh3 u n ~ t s
and w i t h DIOP two diastereomeric complexes
S
were formed w i t h an i n i t i a l
2
Sodium borohydride reduces complex
r a t i o o f 7:3.
c l e a n l y t o butan-2-01
4
as t h e o n l y v o l a t i l e o r g a n i c complex whereas i t s precursor - i s reduced
t o __
trans-but-2-en01
under t h e same c o n d i t i o n s .
T h i s r e s u l t suggests
a c t i v a t i o n o f an i n t e r m e d i a t e primary a l c o h o l 9
- t o hydridic reduction
through t h e carbocation s t a b i l i s i n g a b i l i t y o f t h e 8-Pt-C bond.
S,
CO SF,
-
,0C3:F3
Ci,TOOH
?2?l
Most
P2 Pt
'!Id
Figure 3
Epoxide formation from
2
under a c i d i c c o n d i t i o n s
- 5 -
- 7 -
Acknowledgment
Ue thank SERC f o r a CASE s t u d e n t s h i p awarded
t o R.A.J.
[I1
Sheldon. J . K .
R.A.
Kochi.
'Metal-catalysed o x i d a t i o n s o f organic
compounds'' Academic Press. N.Y.
[21
Y. Tatsuno, S . Otsuka. J . Am.
Ugo. G.M.
R.
Zanderighi. A.
1981.
Chem. S O C .
Fusi. D.
103 (1981)
Carreri.
5832;
i b i d_
102 (1980)
_
3745.
131
Ugo. F.
R.
Conti. S.
Commun. (1968) 1498;
Cenini. R. Mason. J. Chem. S O C . Chem.
P.J.
Hayward. D.M.
~
significantly.
the r e a c t i o n o f complex
Nyman. _
J. Amer. Chem. S O C . , 92 (1970) 5873.
____-
[41
R.A.
Sheldon. J.A.
[51
G.
Paiaro.
L.
Pandolfo. Angeu Chem. I n t . Ed.
(1975) 115
(1981) 288.
i n t h e presence o f a
c.f.
In benzene, a s i g n i f i c a n t p r o p o r t i o n
of
o f trans-but-2-en01
van Doom. J. Organometal Chem
i n C H 2 C l Z w i t h CF3COZH g i v e s
2.
- even
,907. o f 1-formyl-2-methyloxirane
s u b s t a n t i a l excess o f PPh3.
2
Blake. 6 . U i l k i n s o n .
C.J.
i s formed b y s i d e - r e a c t i o n .
t h e adduct formed from t h e t r i c y c l o h e x y l p h o s p h i n e analogue
1 and
dimethylacetylenedicarboxylate. Clark. H.C..
Goel. A.B
Concomitant
~
Uong. C.S.
formation o f fi(triflooroacetato)fi(triphenylphosphine)platinum
Chem. SOC. lOO(1978) 6241.
J . Am.
is
[61
M.
Green. J.A.K.
Howard. P. Mitrachacon. H. P f e r r e r .
observed.
J.L.
Spencer.
F.G.A.
Stone. P. Uooduard.
J.
Chem. Soc.
Dalton.
I t i s s t r i k i n g t h a t epoxide f o r m a t i o n i s u n a f f e c t e d by PPh3. a
well-established t r a p
~
/lo/
f o r p e r o x i d i c species.
This,
Trans.
(1979) 306; on mechanistic grounds i t i s p o s s i b l e t h a t the
coupled w i t h
a c e t y l group i n
t h e s t e r e o s e l e c t i v i t y of
6
i s o - t o p l a t i n u m r a t h e r t h a n 6 - t o p l a t i n u m as
93% which compares w i t h 85% i n t h e d i r e c t
proposed.
e p o x i d a t i o n of --but-Z-enol
by hydrogen peroxide. suggests t h a t
[71
L. Carlton.
Read. J . H a l . Catal
G.
o x i d a t i o n occurs w i t h i n t h e c o o r d i n a t i o n sphere. u n l i k e t h e p l a t i n u m [ol
Pure A w l . Chem
c a t a l y s e d o x i d a t i o n o f PPh
1101.
lo
(1981) 133;
H. Mimoun
(1981) 2389. and e a r l i e r papers by these
An a t t r a c t i v e mechanism i s shown i n
authors;
Figure 3 and i n v o l v e s a 11.21 peroxide s h i f t .
M.T.
Altay. H. Preece. G. S t r u k u i . B.R.
f a l l o w e d b y fragmentation
J.
t o g i v e t h e epoxide.
53
Chem. Sac. Chem. Commun. (1982) 406.
The o v e r a l l r e a c t i o n . i n v o l v i n g s t o i c h i o m e t r i c
[81
- 6 -
B.U.
Erickson. Organic Syntheses 54 (1974) 19.
- 8 -
Jones
[91
Employing Runge-Kutta i n t e g r a t i o n s of the possible r a t e
beschreiben/2/. Wir berichten nun uber den neuen Tellur-
equations f o r the d i f f e r e n t mechanisms programmed on a
komplex U3Te[Mn(C0)2 (q5-CsH5)1,
Heulett-Packard HP
1101
A.
85 microcomputer.
Sen. J. Halpern. J. Am.
Chem. SOC.
99
(1977) 8337;
6
in
(1967) 92.
c.f.
A.
der nach der Rontgen-
kann daher angenommen werden, da8 das zentrale Telluratom
G . U i L k e . H. Schott, P. Heimbach. Angeu Chem. I n t . Ed.
[111
($1,
strukturanalyse ein fast ebenes MnsTe-Gerust besitzt. Es
4 als Sechselektronendonor fungiert und drei sternformiy
anqeordnete Mn-Te-Doppelbindungen zu den [Mn(C0)z(n5-CsHa)
Heumann.
F. Chauvet.
0 . Waegell. Tetrahedron L e t t e r s
1-
Fragmenten ausbildet, denen jeweils 2 Elektronen zur Errei-
(1982) 2767.
chung der Edelyaskonfiguration fehlen.
Tabelle 1.
Received August 18. 1982
/Z
Strukturdaten von Mehrkernkomplexen mit substituentenfreien Hauptyruppenelementen.
134 S /
Mn,Ge
nahezu planar
IWmkelsumme am Ge 360.0°)
d(Mn=Ge)
d(Mn-Ge1
dlMn-Mn)
226.0
235.9
238.0
298.2
pm
pm
pm
pm
Mn3Te nahezu planar
(Winkelsumme am Te 359.9O)
246.9
247.4
251.2
d(Mn...Mn) >425
d(Mn=Te)
pm
pm
~m
pm
Als kovalente Einfachbindunysradien werden a~~gegeben'~':
S 104,
Se 117, Te 137 pm; Cr 117.6,
- 9 -
-
Mn
117.1 pm.
11 -
4 entstand bei der Einwirkung von uberschiissigem Tellurwas-
to be cited as
Angew. Chem. Suppl.
1983,10-22
zu zitieren als
Angew. Chem. Suppl.
1983,10-22
serstoff, TeH2, auf eine Lssuny des THF-stabilisierten Komplexfragments [Mn(CO)2(~~-CaH5)],das bei der Photolyse von
Mn(C0)3(nS-C,Hs),
Cyclopentadienyl-tricarbonylmangan,
D Verlag Chernie GrnbH. D-6940Weinhem, 1983
0721 422118310101 0010802 5010
Te2[Mn(C0)2(qS-CsH.)
Tellur als Sechselektronendonor
-
in THF
erhalten wird. Als Nebenprodukt lieL3 sich in yeringer Menge
Synthese und Struktur von
(-5 ) isolieren. ES handelt sich urn die
1,
ersten Komplexe eines Metalls der VII. Nebengruppe mit substituentenfreiem Tellur.
Tabelle 2 . Spektroskopische Daten der Komplexe
4
und
Von Max Herberhold, Dietmar Reiner und Dietmar Neugebauer
Komplex
T e [ M n ( C O ) a (qs-CsHs)
13
5
T e z [ M n ( C O ) z lrl"-CsHs)
13
Bei der Verbriickung koordinativ ungesattiyter Uberqanysme-
[a-'1
tall-Komplexfraqmente durch substituentenfreie Hauptyruppen-
IR: VICO)
elemente konnen - unter Einbeziehung sXmtlicher Valenzelek-
zn Etherl6,sung
tronen des Bmckenatoms
werden (Tabelle 1).
-
f
d Mehrfachbindungen ausgebildet
So werden fur den Sechselektronendonor
Schwefel in der nahezu linearen CrSCr-Brucke von
Crs-Dreifachbindungen formuliert'".
1 zwei
2
mit zwei Mn=Ge-Doppelbindunyen, im nahezu planaren Mn,GeGeriist von
3
[ppml
mit einer Doppel- und zwei Einfachbindungen
1928"s.
1909m. 1 8 8 6 ~
blC.Hsl
5.23(s)
6(CsHs)
87.8(5)
1994s. 1982m.sh.
1935vs
1919~s. 1901s. 1886m.sh
6(CsHs)
5.23(s)
in [Ds]AcetOn, 25 OC
"c-NMR
Der Vierelektronendo-
nor Germanium la8t sich in der linearen MnGeMn-Briicke von
'H-NMR
1998m. 1992m.sh. 1940s
[ppml
i n [Ds]Aceton, -80 "C
MS
6 ~ 0 ) 232.0(s)
Idel
658 [ M I +
658 [M-Tel+
(bez. auf "OTe)
612 [M-MnlC011(CsHs)
Die IR- und NMR-Spektren Yon
4
und
I+
2 stimmen fast volliq
iiberein (Tabelle 2 ) ; nur einiye IR-Absorptionen zeigen qe-
* Prof.
Or. M. Herberhold, Dr. 0. Reiner
Laboratorium fur Anorganische Chemie der Universitat
Bayreuth, Universitatsstr. 30. D-8580 Bayreuth
D r . D. Neugebauer
Anorqanisch-chemisches Institut der Technischen Universitlt Miinchen, Lichtenbergstr. 4 . D-8046 Garchiny
** Diese Arbeit wurde von der Deutschen Forschunqsgemeinschaft und dem Fonds der Chemischen Industrie unterstiitzt.
-
10 -
rinye Intensitatsunterschiede. Im v(C0)-Bereich treten jeweils 6 Absorptionen auf. Die 1H-NMR-Spektren lassen nur
1 Singulett fur die drei Cyclopentadienylringe erkennen. Im
"C-NMR-Spektrum
von
4 wird ebenfalls nur jeweils ein Singu-
lett far den Funfring und fiir die CO-Liganden erhalten. Im
- 12
-
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