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Gas phase ion chemistry :
Tetrahedron printed in
Letters, Vo1.27, Great Britain
No.1,
pp
33-36,
GAS PHASE ION CHEMISTRY
A COMPARATIVE
STUDY OF REACTION
OF FIRST ROW TRANSITION
Helene MESTDAGH, ECOLE NORMALE
Nicole
:
METAL CATIONS
MORIN, Christian
SUPERIEURE,
24, rue Lhomond,
oo40-4039/86 $3.00 + .OO 01986 Pergamon Press Ltd.
1986
LABORATOIRE
WITH Z-METHYL
PROPANE
ROLAND0
DE CHIMIE,
75231 PARIS CEDEX 05 - FRANCE.
ABSTRACT : The gas phase reactivity of first row transition metal cations with Z-methylpropane was investigated using a tripZe quadrupole qapss spfctrometer. This reactivity is very variable depending on the natyre of+the petal : Ti+ and V give mainly the multiple collision (reported to be unreactive under other ~;~$;;o;;;C9&?I ~h~e;;HI;?c; ;9, ;z$, zn.+ Nz cleave C-H and C-C bonds of Z-methylpropane and react further. The subject
of
transform
gas-phase several
mass
reactions
recent
spectrometry
and ion beam techniques Most
of these
company
(25)
were
hydrocarbon
with
hydrocarbons
have
resonance
(l-4),
Fourier
spectroscopy
(14,15)
cyclotron
decomposition
been
the
focus
on group
8 transition
metals,
while Mn+, Cr+ (20) and Cuf
to be unreactive.
have
of
compared
metal
triple the
quadrupole
gas-phase
by
volatilized
the
at a pressure
first
collision
from
mass
reactivity
a salt
quadrupole
on the order of 10
The gas pressure
above-mentioned
multiple
ions,
selected
the analyzer. the
ions
ion
spectrometer
(24)
of
transition
first
row
from
the
NERMAG
metal
ions
2-methylpropane. The
(25),
we
metal
using
collision-activated
(5-13),
Using a prototype
towards
transition
(16-22).
investigations
(23) are reported
of
investigations
and/or
techniques, products.
The
a
of the collision
large
collision
matrix
using
a FAB source
and reacted in the collision chamber with the -3 torr. The resulting ions were then detected in
the length
allowing
in a glycerol
energy
extent
of
chamber
conversion
is low : 0
are larger
than in
and the detection
to 1 eV in the center
of
of mass
frame.
Using (very
small
similar
conditions,
cross-section,
cross-sections with
these
(lo-100 R2). abundances,
and gave results
1 x2)
all
M+
appeared
ions
studied
to react
In all the cases
the reactions
in agreement
the
where
were carried
with the proposed
33
with
several
except
(no reaction)
2-methylpropane, isotopes
out successively
formula.
K+
with
and Ca+
comparable
of the metal are present on all the isotopic
ions
34
From reactivities
Table
it can be seen that
towards
2-methylpropane.
the different
- Ti+ and Vc : the major reaction of
4 10 molecules CH
2
indicate
that
reactive
towards
primary major
the
product
addition
is
Ti(C4H8) +
Mn+,
(3).
under
retains
its
Cr(C4H8)+,
under
ion beam
Mn+
ligand exchange
the formation
(d5 and dl"
products
2-methylpropane
is more
Under
ICR
conditions
(only
: with 2-methylpropane
alkanes
interesting of new
to know
carbon-carbon
unreactive
of Cr+ with
(2).
(20). Although
M(C4HlO)
+
the
whether bonds.
the Their
. Cr(C4
pathway is the neat + HlD) was reported to
: its CAD spectrum suggests
reaction
(27), no Mn (alkane)+
Both
complex
that
2-methylpropane
the C4HlO
under
of Mn(ligand)+
had been reported molecule
unit
ICR conditions
Mn' and Cr+ are unreactive
a variety
of Cr+ and Cu+ a second
In the case
to addition
different
: the main reaction
ions)
ion, giving
2-methylpropane
being
and
itself.
the
investigation.
(2). Direct
conditions
ion
b e particularly
involve
to the metal
and
integrity
gives
It would
Cu+ and Zn+
Cr(CO)+
metal
M+
of
different
:
corresponding
abundances
between
clearly
in three groups
is M(C8H14)+,
relative
the reaction the
ions exhibit
divided
1s known to dehydrogenate
products
of the hydrocarbon from
of
product
The
3 H2.
than
Ti+
collision
are currently
formed
of
product
products),
- Cr+,
be
primary
multiple
structures
loss
2-methylpropane
reaction
observed
and
metal
They can be roughly
towards
alkanes
ions have been prepared
by
yet.
of 2-methylpropane
may react
to give
M(C~H~~)~+. Formation Preliminary
of
studies
indicate
from a secondary
reactive,
Fe+, giving
Co+,
under
ion
obtained
by
Fe(C4H8) + in similar Several being
M(C7H16)+
nickel,
Another from
a
collision
important
energy
under
and
(C,H9+)/ at
C4H9+
similar
of
FeCO+
arises
and/or CU(C~H~O)~+.
literature, M(C3H6)+
group
8 metal
(l-3,7,14,16,
collision
energy
19-21).
(20,Zl).
2-methylpropane
with
ions
also
are The
the
most
abundance
with those reported The
CAD
affords
spectrum Fe(C3H6)+
of
fragment, by
collisions
iron,
or an hydride especially Ni+
or
are observed
M(C8H18)+.
Co+
ion beam conditions
M(C4H12)+,
in addition, important
of and
the major ones in the
Ar+, generated
case
of
structure. with
nickel,
is C4Hgt.
is an endothermic
Since
reaction
direct
observed
(16, 20), C4H9+ might be a secondary
product.
For comparison,
least
(14).
case
2-methylpropane
from
of ion abundances that
from Fe to Ni, are in good agreement
from multiple
in the
suggesting
pressure,
of Cu(C4HlO)'
might have either a M(CH3)4+
abstraction high
reaction
proportions
case of Cu+ the ratio
the with
M(C4H8)+
with
products and,
in
decreasing
conditions
: for Mn+ and Zn+ it is the major product.
observed
: as expected
particular
in
M(C,H,+)/M(C,H,)+,
Fe(C4H10)+
that
reaction
Nif
ratios
beam
is also
increases
(Cu(C4HlO) + + CU(C~H~O)~+) partially
+
C4H9
from non-neutralized
Ar in the FAB beam, was
hydride only
at
reaction
35
TABLE : reecting relative value is
("y_!of the main ionic reactjon Relative abundance products between different ions !.!+and 2-methylpropane under the same pressure conditions. All the ions whose abundance was found larger than 10% in at least one case are mentioned. When no' indicated the corresponding relative abundance is less than 1%.
Reacking
ion (biO Ca
Product ions (mass)
48 Ti
5: v
52 (a) Cl?
55 (a)
56
59
58
63
64 (a)
40
Mn
Fe
Co
Ni
Cu
Zn
Ar
100
39
100
100
100
51
90
86
30
--
--
1
--
--
--
6
11
7
4
3
3
--
2
1
1
1
16
26
18
15
10
2
10
32
15
30
66
71
100
34
100
100
---
--
74
100
50
--
--
--
M+(m)
100
C3i15t(41) C3H7+(43) c4h9+(57)
4
C3Uc?l'(n+12)
--
--
--
C H M'(m-1-56) 48
..
10
5
1
--
62
21
3
7
--
--
CqH10M+(m+5&;
-.-
--
3
98
16
4
3
2
100
59
--
C4:+IlM+[m+59: L
2
--
--
5
6
17
4
10
4
3
--
--
--
--
--
--
35
47
81
--
--
--
)
--
23
i
--
--
2
--
--
--
--
--
C5H,3M+(m+'/3j I
--
2
2
_-
--
18
--
--
--
--
--
C5H14M+(m+74)
--
5
5
--
--
34
6
5
--
-_
--
C5H15M+(m+75j
--
--
--
--
--
16
1
__
--
--
--
C7H,2M+(m+96)
--
29
--
--
--
--
--
2
-_
--
--
C7H16M+(m+100)
--
2
--
--
--
70
58
70
--
--
--
C8!!14M+(m+110)
--
92
100
--
--
--
--
__
--
--
--
C4H12M'(m+60)
c
c’
‘I
12?t+ ( ;,,-i-72
!a! K(H,3)i(n+:8)
(!Y!
ions are also observed, since H,C) 'was present as an impurity. 40 ctker isotopes studied : T1, "Cr, 3dFe, "Ni, o'Cu, bbZn, "Zn.
36
reacted
with
indicating observed
2-methylpropane
a much
: hydride
ethane giving
source
chemistry multiple formation never
abstraction
conclusion, allowed
collisions
reported high
compare specific
appears
of M(C4H10)+
relatively
the same conditions.
section
than
affording
to
complexes to
occur
pressure.
The
the
the
transfer
phase
mass
chemistry
on the nature this
probably
structures
of
Only
the
of
reaction
one reaction
of
Another
requires
with
metal
a FAB
ions.
This
and the possibility
important
feature
to a metal
both
different
coupled
different
an alkane
low
reaction
is
to react with
(28).
spectrometry
of the metal,
specificity.
: such an addition directly,
Ar + could be detected,
cases.
At low energy Ar+ was reported
quadrupole
gas
No unreacted
preceding
and no charge
depending enhance
in
C4H9+.
the use of triple
to
is extremely
been
under
cross
C2H5 + among other products
In ion
larger
is the
ion, which
collision
energy
products
are
of
had and
under
investigation. We are re,
Laboratoire
for their data
indebted
to the Ministbre
de
Chimie)
and the CNRS
financial
support
of this work.
system
for MS/MS
and for the generous
and the NERMAG
de 1'Education (UA 1110, We thank
Nationale
Laboratoire Daniel
(Ecole Normale
de 1'Activation
JAOUEN who modified
staff for their kind and efficient
Superieu-
Moleculaire) the SIDAR 150
technical
assistance
loan of a FAB source.
REFERENCES (1)
(2) (3) (4) (5) (6) (7) (8) (9) (IO) (11) (12) (13) (14) (15) (16) (17) (18) (19)
(20) (21) (22) (23) (24) (25) (26) (27) (28)
J. Allison, R.B. Freas and D.P. Ridge, J. Am. Chem. Sot., 1979, 101, 1332. R.B. Freas and D.P. Ridge,J. Am. Chem. Sot., 1980, 102, 7129. G.D. Byrd, R.C. Burnier and B.S. Freiser, J. Am. Chem. Sot., 1982, 104, 3565. M.M. Kappes and R.H. Staley, J. Am. Chem. Sot., 1982, 2, 1813. G.D. Byrd and B.S. Freiser, J. Am. Chem. Sot., 1982, 104, 5944. Chem. Sot., 1983, 105, 736. D.B. Jacobson and B.S. Freiser, J. Am. Chem. Sot., 1983, 105, 5197. D.B. Jacobson and B.S. Freiser, J. Am. D.B. Jacobson and B.S. Freiser, J. Am. Chem. Sot., 1983, 105, 7484. D.B. Jacobson and B.S. Freiser, J. Am. Chem. Sot., 1983, 105, 7492. 1984, 513. D.B. Jacobson and B.S. Freiser, Organometallics, D.B. Jacobson, G.D. Byrd and B.S. Freiser, Inorg. Chem., 1984, 553. D.B. Jacobson and B.S. Freiser, J. Am. Chem. Sot., 1985, 107, 72. D.B. Jacobson and B.S. Freiser, J. Am. Chem. Sot., 1985, 107, 1581. B.S. Larsen and D.P. Ridge, J. Am. Chem. Sot., 1984, 106, 1912. D.A. Peake, M.L. Gross and D.P. Ridge, J. Am. Chem. Sot., 1984, 106, 4307. P.B. Armentrout and J.L. Beauchamp, J. Am. Chem. Sot., 1981, 103, 784. Chem. Sot., 1981, 103, 6624. P.B. Armentrout, L.F. Halle and J.L. Beauchamp, J. Am. P.B. Armentrout and J.L. Beauchamp, J. Am. Chem. Sot., 1981, 103, 6628. L.F. Halle, R. Houriet, M.M. Kappes, R.H. Staley and J.L. Beauchamp, J. Am. Chem. sot., 1982, 104, 6293. L.F. Halle, P.B. Armentrout and J.L. Beauchamp, Organometallics, 1982, 963. R. Houriet, L.F. Halle and J.L. Beauchamp, Organometallics, 1983, 1818. M.A. Tolbert and J.L. Beauchamp, J. Am. Chem. Sot., 1984, 106, 8117. C.J. Cassady and B.S. Freiser, J. Am. Chem. Sot., 1985, 107, 1566. R.A. Yost and C.G. Enke, J. Am. Chem. Sot., 1970, 100, 2274. C. Beaugrand, G. Devant, C. Rolando, "Up-grading a large size quadrupole GC/MS to Abstracts of the 31st Annual Conference on Mass a triple quadrupole GC/MS/MS, Spectrometry and Allied Topics, Boston, 1983. C. Javanaud and D. Eagles, Org. Mass. Spectrom., 1983, g, 93. J.S. Uppal and R.M. Staley, J. Am. Chem. Sot., 1982, 104, 1238. H. Chatham, D. Hils, R. Robertson and A.C. Gallagher, J. Chem. Phys., 1983, 79, 1301.
(Received in France 25 October 1985)
Letters, Vo1.27, Great Britain
No.1,
pp
33-36,
GAS PHASE ION CHEMISTRY
A COMPARATIVE
STUDY OF REACTION
OF FIRST ROW TRANSITION
Helene MESTDAGH, ECOLE NORMALE
Nicole
:
METAL CATIONS
MORIN, Christian
SUPERIEURE,
24, rue Lhomond,
oo40-4039/86 $3.00 + .OO 01986 Pergamon Press Ltd.
1986
LABORATOIRE
WITH Z-METHYL
PROPANE
ROLAND0
DE CHIMIE,
75231 PARIS CEDEX 05 - FRANCE.
ABSTRACT : The gas phase reactivity of first row transition metal cations with Z-methylpropane was investigated using a tripZe quadrupole qapss spfctrometer. This reactivity is very variable depending on the natyre of+the petal : Ti+ and V give mainly the multiple collision (reported to be unreactive under other ~;~$;;o;;;C9&?I ~h~e;;HI;?c; ;9, ;z$, zn.+ Nz cleave C-H and C-C bonds of Z-methylpropane and react further. The subject
of
transform
gas-phase several
mass
reactions
recent
spectrometry
and ion beam techniques Most
of these
company
(25)
were
hydrocarbon
with
hydrocarbons
have
resonance
(l-4),
Fourier
spectroscopy
(14,15)
cyclotron
decomposition
been
the
focus
on group
8 transition
metals,
while Mn+, Cr+ (20) and Cuf
to be unreactive.
have
of
compared
metal
triple the
quadrupole
gas-phase
by
volatilized
the
at a pressure
first
collision
from
mass
reactivity
a salt
quadrupole
on the order of 10
The gas pressure
above-mentioned
multiple
ions,
selected
the analyzer. the
ions
ion
spectrometer
(24)
of
transition
first
row
from
the
NERMAG
metal
ions
2-methylpropane. The
(25),
we
metal
using
collision-activated
(5-13),
Using a prototype
towards
transition
(16-22).
investigations
(23) are reported
of
investigations
and/or
techniques, products.
The
a
of the collision
large
collision
matrix
using
a FAB source
and reacted in the collision chamber with the -3 torr. The resulting ions were then detected in
the length
allowing
in a glycerol
energy
extent
of
chamber
conversion
is low : 0
are larger
than in
and the detection
to 1 eV in the center
of
of mass
frame.
Using (very
small
similar
conditions,
cross-section,
cross-sections with
these
(lo-100 R2). abundances,
and gave results
1 x2)
all
M+
appeared
ions
studied
to react
In all the cases
the reactions
in agreement
the
where
were carried
with the proposed
33
with
several
except
(no reaction)
2-methylpropane, isotopes
out successively
formula.
K+
with
and Ca+
comparable
of the metal are present on all the isotopic
ions
34
From reactivities
Table
it can be seen that
towards
2-methylpropane.
the different
- Ti+ and Vc : the major reaction of
4 10 molecules CH
2
indicate
that
reactive
towards
primary major
the
product
addition
is
Ti(C4H8) +
Mn+,
(3).
under
retains
its
Cr(C4H8)+,
under
ion beam
Mn+
ligand exchange
the formation
(d5 and dl"
products
2-methylpropane
is more
Under
ICR
conditions
(only
: with 2-methylpropane
alkanes
interesting of new
to know
carbon-carbon
unreactive
of Cr+ with
(2).
(20). Although
M(C4HlO)
+
the
whether bonds.
the Their
. Cr(C4
pathway is the neat + HlD) was reported to
: its CAD spectrum suggests
reaction
(27), no Mn (alkane)+
Both
complex
that
2-methylpropane
the C4HlO
under
of Mn(ligand)+
had been reported molecule
unit
ICR conditions
Mn' and Cr+ are unreactive
a variety
of Cr+ and Cu+ a second
In the case
to addition
different
: the main reaction
ions)
ion, giving
2-methylpropane
being
and
itself.
the
investigation.
(2). Direct
conditions
ion
b e particularly
involve
to the metal
and
integrity
gives
It would
Cu+ and Zn+
Cr(CO)+
metal
M+
of
different
:
corresponding
abundances
between
clearly
in three groups
is M(C8H14)+,
relative
the reaction the
ions exhibit
divided
1s known to dehydrogenate
products
of the hydrocarbon from
of
product
The
3 H2.
than
Ti+
collision
are currently
formed
of
product
products),
- Cr+,
be
primary
multiple
structures
loss
2-methylpropane
reaction
observed
and
metal
They can be roughly
towards
alkanes
ions have been prepared
by
yet.
of 2-methylpropane
may react
to give
M(C~H~~)~+. Formation Preliminary
of
studies
indicate
from a secondary
reactive,
Fe+, giving
Co+,
under
ion
obtained
by
Fe(C4H8) + in similar Several being
M(C7H16)+
nickel,
Another from
a
collision
important
energy
under
and
(C,H9+)/ at
C4H9+
similar
of
FeCO+
arises
and/or CU(C~H~O)~+.
literature, M(C3H6)+
group
8 metal
(l-3,7,14,16,
collision
energy
19-21).
(20,Zl).
2-methylpropane
with
ions
also
are The
the
most
abundance
with those reported The
CAD
affords
spectrum Fe(C3H6)+
of
fragment, by
collisions
iron,
or an hydride especially Ni+
or
are observed
M(C8H18)+.
Co+
ion beam conditions
M(C4H12)+,
in addition, important
of and
the major ones in the
Ar+, generated
case
of
structure. with
nickel,
is C4Hgt.
is an endothermic
Since
reaction
direct
observed
(16, 20), C4H9+ might be a secondary
product.
For comparison,
least
(14).
case
2-methylpropane
from
of ion abundances that
from Fe to Ni, are in good agreement
from multiple
in the
suggesting
pressure,
of Cu(C4HlO)'
might have either a M(CH3)4+
abstraction high
reaction
proportions
case of Cu+ the ratio
the with
M(C4H8)+
with
products and,
in
decreasing
conditions
: for Mn+ and Zn+ it is the major product.
observed
: as expected
particular
in
M(C,H,+)/M(C,H,)+,
Fe(C4H10)+
that
reaction
Nif
ratios
beam
is also
increases
(Cu(C4HlO) + + CU(C~H~O)~+) partially
+
C4H9
from non-neutralized
Ar in the FAB beam, was
hydride only
at
reaction
35
TABLE : reecting relative value is
("y_!of the main ionic reactjon Relative abundance products between different ions !.!+and 2-methylpropane under the same pressure conditions. All the ions whose abundance was found larger than 10% in at least one case are mentioned. When no' indicated the corresponding relative abundance is less than 1%.
Reacking
ion (biO Ca
Product ions (mass)
48 Ti
5: v
52 (a) Cl?
55 (a)
56
59
58
63
64 (a)
40
Mn
Fe
Co
Ni
Cu
Zn
Ar
100
39
100
100
100
51
90
86
30
--
--
1
--
--
--
6
11
7
4
3
3
--
2
1
1
1
16
26
18
15
10
2
10
32
15
30
66
71
100
34
100
100
---
--
74
100
50
--
--
--
M+(m)
100
C3i15t(41) C3H7+(43) c4h9+(57)
4
C3Uc?l'(n+12)
--
--
--
C H M'(m-1-56) 48
..
10
5
1
--
62
21
3
7
--
--
CqH10M+(m+5&;
-.-
--
3
98
16
4
3
2
100
59
--
C4:+IlM+[m+59: L
2
--
--
5
6
17
4
10
4
3
--
--
--
--
--
--
35
47
81
--
--
--
)
--
23
i
--
--
2
--
--
--
--
--
C5H,3M+(m+'/3j I
--
2
2
_-
--
18
--
--
--
--
--
C5H14M+(m+74)
--
5
5
--
--
34
6
5
--
-_
--
C5H15M+(m+75j
--
--
--
--
--
16
1
__
--
--
--
C7H,2M+(m+96)
--
29
--
--
--
--
--
2
-_
--
--
C7H16M+(m+100)
--
2
--
--
--
70
58
70
--
--
--
C8!!14M+(m+110)
--
92
100
--
--
--
--
__
--
--
--
C4H12M'(m+60)
c
c’
‘I
12?t+ ( ;,,-i-72
!a! K(H,3)i(n+:8)
(!Y!
ions are also observed, since H,C) 'was present as an impurity. 40 ctker isotopes studied : T1, "Cr, 3dFe, "Ni, o'Cu, bbZn, "Zn.
36
reacted
with
indicating observed
2-methylpropane
a much
: hydride
ethane giving
source
chemistry multiple formation never
abstraction
conclusion, allowed
collisions
reported high
compare specific
appears
of M(C4H10)+
relatively
the same conditions.
section
than
affording
to
complexes to
occur
pressure.
The
the
the
transfer
phase
mass
chemistry
on the nature this
probably
structures
of
Only
the
of
reaction
one reaction
of
Another
requires
with
metal
a FAB
ions.
This
and the possibility
important
feature
to a metal
both
different
coupled
different
an alkane
low
reaction
is
to react with
(28).
spectrometry
of the metal,
specificity.
: such an addition directly,
Ar + could be detected,
cases.
At low energy Ar+ was reported
quadrupole
gas
No unreacted
preceding
and no charge
depending enhance
in
C4H9+.
the use of triple
to
is extremely
been
under
cross
C2H5 + among other products
In ion
larger
is the
ion, which
collision
energy
products
are
of
had and
under
investigation. We are re,
Laboratoire
for their data
indebted
to the Ministbre
de
Chimie)
and the CNRS
financial
support
of this work.
system
for MS/MS
and for the generous
and the NERMAG
de 1'Education (UA 1110, We thank
Nationale
Laboratoire Daniel
(Ecole Normale
de 1'Activation
JAOUEN who modified
staff for their kind and efficient
Superieu-
Moleculaire) the SIDAR 150
technical
assistance
loan of a FAB source.
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(20) (21) (22) (23) (24) (25) (26) (27) (28)
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(Received in France 25 October 1985)