N
X
C
Hal
O
N
S
P Si
Natural
Products
Solvents
C
C
C
C C
C
8.10 Sulfur Compounds
415
which further lose CS and CO, respectively, to give C 5 H 5
+ (m/z 65):
S
O
S
O
S
+
O
+
C 5 H 5
+
m/z 65
S
[M -29]
+
– SO
– O
– CH O
.
[M -48]
+ .
[M -16]
+ .
– PhS
.
– CS
– CO
– PhO
.
+ .
+ .
+ .
+ .
ESI-MS/MS: Elimination of an aryl radical.
Ion series: Besides the ions described under Fragmentation, mainly fragments of
the aromatic type, i.e., C n H n and C n H n±1 (m/z 39, 51–53, 63–65, 75–77, …), as well
as O- and S-containing ions.
Intensities: Intensive peaks mainly in the high mass range.
Molecular ion: Very strong. Characteristic 34 S isotope peak at [M+2] +· and [frag+2]
for S-containing fragments (4.5% per S atom).
Aliphatic Sulfones [4,5]
Fragmentation: Fragmentation of the S–C bond with the charge remaining on either
side. Single and double H rearrangements to give RS(O)OH +· and RS(OH) 2
+ . The
probability of the double H rearrangement increases with increasing chain length.
If one of the substituents is unsaturated, rearrangement to RS(O)O–alkene followed
by cleavage of the S–O bond yields the ion RSO + .
S C 4 H 9
C 4 H 9
O
O
S
C 4 H 9
O
O H
– OH
.
C
H
+
O
S
C 4 H 9
+
m/z 161
C 4 H 9
+
m/z 57 (100% )
C 4 H 9 SO 2
m/z 121
C 4 H 9 S
O
O H
C 4 H 9 S
O H
O H
+
O
S
O
C 4 H 9
+
m/z 149
m/z 123 (70% )
m/z 122
m/z 178
– C 4 H 9 SO 2
.
– C 4 H 9
.
– CH 2 =CH Et
– C 4 H 7
.
– C 2 H 5
.
+
+ .
+ .
.
Ion series: Dominating aliphatic fragments, C n H 2n+1 (m/z 29, 43, 57, …) and
C n H 2n-1 (m/z 27, 41, 55, …). Usually, one significant fragment corresponding to
alk–S(O)OH +· (from the series of m/z 80, 94, 108, …) or alk–S(OH) 2
+ (from the
series of m/z 81, 95, 109, …) can be observed.
Intensities: Intensive peaks mainly of aliphatic fragments in the lower mass range.
Molecular ion: Weak. Characteristic 34 S isotope peak at [M+2] +· and [frag+2] for
S-containing fragments (4.5% per S atom).