JMS Letter
O
O
R2
R1
- 7
R
R1
R2
O
Ph
Ph
Ph
5
a: m/z 91; R =H, R =Ph
5b: m/z 117; R =H, R =CH=CH-Ph
5d: m/z 105; R =H, R =CH Ph
1
2
MS/MS
1 2
Ph
Ph
or
1
2
2
5
5
a m/z 297
H
OH
R3
5
b m/z 323
c m/z 319
d m/z 311
R3
OH
H-transfer
5
5
Ph R1
Ph
Ph
7•H+
m/z 207
Ph
Ph R1
Ion-Neutral
complexes
5
d: R =H, R =Ph
1 3
5
c: R =CH , R =n-Pent
1 3 3
Scheme 2. The proposed fragmentation pathways of 5a–5d by ESI-MS/MS.
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J. Mass. Spectrom. 2011, 46, 856–858