Supplementary material (ESI) for Chemical Communications
This journal is © The Royal Society of Chemistry 2004
Reduction of Nitroaromatics into Arylnitrenium Ions
by Vinyl Halide Cation
Hao Chen, Xubin Zheng, Pengxiang Yang and R. G. Cooks*
Department of Chemistry,`
560 Oval Drive, Purdue University, West Lafayette, IN 47907, USA
Supporting Information
Supplementary material (ESI) for Chemical Communications
This journal is © The Royal Society of Chemistry 2004
CH2=CHCl+.
62
[PhNO2+H]+
124
~
100
Relative Abundance
CH2ClCH2+
63
[PhNO2-d5+H]+
129
PhNH+ Ph(d5 )NH+
92
97
50
[PhNO2+C2H3]+
[PhNO2-d5 +C2 H3]+
107
112
C2H3+
27
150
155
186
191
0
50
100
150
200
m/z
Figure 1S Chemical ionization mass spectrum of a mixture of nitrobenzene and
nitrobenzene-d5 (ca. 1:1 by volume) using 1,2-dichloroethane as the reagent gas. The
phenylnitreium ion (m/z 92) and its benzene-ring-deuterated ion (m/z 97) are produced as
well as the vinylated nitrobenzene ion [PhNO2 + C2H3]+ (m/z 150) and its benzene-ringdeuterated isotopomeric ion (m/z 155).
Supplementary material (ESI) for Chemical Communications
This journal is © The Royal Society of Chemistry 2004
150 [PhN O 2 +C 2 H 3 ]+
a)
PhN H +
92
-CO
-HC HO
10
30
50
70
b)
90
110
130
Ph(d5 )N H +
97
150
170
190
155
[PhN O 2 -d5 +C 2 H 3 ]+
-CO
-HC HO
10
30
50
70
90
110
130
170
190
153
[PhN O 2 +C 2 D 3 ]+
PhN D +
93
c)
150
-CO
-D CD O
10
30
50
70
90
110
130
150
170
190
m/z
Fig 2S CID product ion MS/MS spectra of: a) [PhNO2 + C2H3]+ (m/z 150), b) [PhNO2-d5
+ C2H3]+ (m/z 155) and c) [PhNO2 + C2D3]+ (m/z 153) using argon as target at nominally
10 eV collision energy.
Supplementary material (ESI) for Chemical Communications
This journal is © The Royal Society of Chemistry 2004
NO2
+ CH2
1
+.
CH Cl
2a
O
N
+ O CH CH2 + Cl .
3a
E(kcal/ mol)
4
+
NH
+ CO + HCHO + Cl .
6
+
N
H
O
O
7
8
+ Cl .
5
Reaction Coordinate
Figure 3S Energy diagram for the nitro reduction reaction between nitrobenzene and
CH2=CH-Cl+. . There might be energy barriers for the conversions of the ion 4 into 5 and
of the ion 5 into 6.
Supplementary material (ESI) for Chemical Communications
This journal is © The Royal Society of Chemistry 2004
106
CH2
=CHBr+.
PhNH+
92
[PhNO2 +H]+
124
50
m/z
100
[PhNO2 +C2 H3 ]+
150
150
Figure 4S Product ion mass spectrum showing ion/molecule reaction of nitrobenzene
with CH2=CH-79Br+. (m/z 106) at nominally zero kinetic energy; the phenylnitrenium ion
PhNH+ (m/z 92) is the main product ion.
Supplementary material (ESI) for Chemical Communications
This journal is © The Royal Society of Chemistry 2004
92
PhNH+
a)
+
NH
118
C5 H5 +
65
50
100
+
NH
150
118
b)
C7 H7 +
91
C3 H3 +
C H + C2 H2
C2 H2 5 5
65
39
40
80
-HCN
120
+
NH 118
c) authentic sample
C7 H7 +
91
-HCN
C3 H3 +C H C5 H5 + C2 H2
2 2
65
39
40
m/z
80
120
Figure 5S a) Product ion mass spectrum showing ion/molecule reactions of the
phenylnitrenium ion PhNH+ (m/z 92) with ethyl vinyl ether. The protonated indole ion
(m/z 118) is produced as the main product. Note that the protonation occurs at C3 atom to
form the stable indolenium ion. b) CID product ion MS/MS spectrum of the product ion
at m/z 118 generated from the ionization of a mixture of nitrobenzene, vinyl bromide and
ethyl vinyl ether and c) CID product ion MS/MS spectrum of protonated indole (m/z 118)
generated by CI of authentic indole using isobutane as the reagent gas. Spectra b and c
are identical.
Supplementary material (ESI) for Chemical Communications
This journal is © The Royal Society of Chemistry 2004
Table 1S B3LYP/6-31G(d) Calculated Energies for Molecules and Cations
Species
E (Hartreesa)
ZPEb
Corrected Energiesc
E (kcal/mol)
PhNO2 (1)
CH2=CH-Cl+. (2a)
CH2=CH-Br+.(2b)
Cl. (3a)
Br. (3b)
PhN+(O)OCH=CH2 (4)
PhN+OCH2CH=O (5)
PhNH+ (6)
CO (7)
HCHO (8)
C2H3+ (9)
4–5
(6 +7+ 8+3a) – (1 + 2a)
(6 +7+ 8+3b) – (1 + 2b)
(6 +7+ 8) – (1 + 9)
-436.750585
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-514.5096219
-286.6702715
-113.3094543
-114.5004725
-77.5860437
-
0.103586
0.042114
0.041575
0.000000
0.000000
0.147803
0.147992
0.105611
0.005032
0.026840
0.035076
-
-436.65114
-537.7907221
-2649.307321
-460.1362422
-2571.6569182
-514.33111
-514.36755
-286.56888
-113.30462
-114.47471
-77.55237
-
-d
+ 22.9
-26.7
-29.3
-90.8
a1Hartree=627.51
kcal/mol; bUncorrected; cCalculated as E + ZPE  0.96; dNot Applied.
Table 2S Reductive Chemical Ionization of Substituted Nitrobenzenes
Compounds
Reagent gases
nitrobenzene
1,2-dichloroethane
1,2-dichloroethane-d4
vinyl bromide
1,2-dichloroethane
1,2-dichloroethane
1,2-dichloroethane
1,2-dichloroethane
1,2-dichloroethane
4-nitrotoluene
4-bromo-1-nitrobenzene
1,3-dinitrobenzene
2,4-dinitrotoluene
2,4,6-trinitrotoluene (TNT)
aContaining 79Br.
m/z of the generated arylnitrenium ions
(m/z of its CID fragment ions)
92(39,65)
93(39,65)
92(39,65)
106(39,51,65,79)
170a(91,143a)
137(52,54,79,91)
151(93,104,105)
196(66,80,91,92,121,138,150)
m/z of the generated vinylated ions
(m/z of its CID fragment ions)
150(92)
153(93)
150(92)
164(106)
228a(170a)
195(137)
209(151)
254(196)