Stability of diazocarbonyl compounds under the conditions of gas chromatography and chromatography-mass spectrometry analysis

Article abstract of DOI:10.1134/S1070363212100088

The gas chromatographic analysis of alkyldiazoacetates N ₂CHCO₂R (R = CH₃ - C₄H₉), α-aliphatic diazoketones RCOCHN₂ (R = C₃H ₇, C₅H₁₁, and C₉H₁₉), and aryl-substituted diazoketones Ph (CH₂)_nCOCHN₂ (n = 0-2) is shown to be possible when their retention temperatures are below the boiling points of compounds of this series at atmospheric pressure without decomposition (about 140°C). At higher temperatures occurs partial or complete decomposition of α-diazoketones in chromatographic columns to form ketenes. Among the impurities in the reaction mixtures at the diazotization of corresponding alkyl glycinates were identified for the first time the nitrate esters of glycolic acid O₂NOCH₂CO₂R, as well as the dimeric products. All diazocarbonyl compounds and the impurities were characterized by mass spectra. For the first time their gas chromatographic retention indices were determined. Pleiades Publishing, Ltd., 2012.

Full text of DOI:10.1134/S1070363212100088

ISSN 1070-3632, Russian Journal of General Chemistry, 2012, Vol. 82, No. 10, pp. 1675–1685. © Pleiades Publishing, Ltd., 2012.
Original Russian Text © T.A. Kornilova, A.I. Ukolov, R.R. Kostikov, I.G. Zenkevich, 2012, published in Zhurnal Obshchei Khimii, 2012, Vol. 82, No. 10,
pp. 1663–1674.
Stability of Diazocarbonyl Compounds
under the Conditions of Gas Chromatography
and Chromatography-Mass Spectrometry Analysis
T. A. Kornilova, A. I. Ukolov, R. R. Kostikov, and I. G. Zenkevich
St. Petersburg State University, Universitetskii pr. 26, St. Petersburg, 198504 Russia
e-mail: izenkevich@mail15.com
Received March 22, 2012
Abstract—The gas chromatographic analysis of alkyldiazoacetates N2CHCO2R (R = CH3 – C4H9), α-aliphatic
diazoketones RCOCHN2 (R = C3H7, C5H11, and C9H19), and aryl-substituted diazoketones Ph (CH2)nCOCHN2
(n = 0–2) is shown to be possible when their retention temperatures are below the boiling points of compounds
of this series at atmospheric pressure without decomposition (about 140°C). At higher temperatures occurs
partial or complete decomposition of α-diazoketones in chromatographic columns to form ketenes. Among the
impurities in the reaction mixtures at the diazotization of corresponding alkyl glycinates were identified for the
first time the nitrate esters of glycolic acid O2NOCH2CO2R, as well as the dimeric products. All diazocarbonyl
compounds and the impurities were characterized by mass spectra. For the first time their gas chromatographic
retention indices were determined.
DOI: 10.1134/S1070363212100088
Among the significant limitations of implementa-
tion of gas chromatography for the separation, iden-
tification, and quantification of organic compounds is
the instability of the latter in the course of analysis.
The possible conversion of analytes at the preparation
of samples, for example, their hydrolysis with water
vapor or oxidation with the air oxygen [1] can be
eliminated by a modification of dosing devices and
procedures. It is harder to detect the interaction of the
components of the analyzed mixtures with each other
(for example, the hydrolysis of propylene carbonate by
the water traces at the sample input temperature [2]) or
their thermal decomposition during analysis. A
possible way to overcome the last restriction lies in
estimation of the temperature limits of structural
stability of the analytes and the relevant change of
conditions for their separation, including reduction of
temperature in all the units of a gas chromatographic
system. For example, 4-acyl-1,3,4-oxadiazolines without
substituents in position 2 are stable at the injector
temperature up to ~150ºC, but at higher temperatures
they are transformed into the corresponding monoacyl
hydrazones through decarbonylation [3].
determine the possibility of analysis of the thermally
unstable compounds are absent from the literature [4].
In one of the recent symposia on capillary
chromatography (Italy, 2010) this issue was considered
as relevant for improving capillary columns in the
report of the Restek company [5]. In general, the
modern design of chromatographic equipment allows
its use for the analysis of unstable compounds like
organic peroxides [6]. However, gas chromatographic
analysis is practically not applied yet to many
thermally unstable compounds, e.g., hypohalides,
azides, hydroxylamines, isonitriles, hydroperoxides
etc., including the diazocarbonyl compounds considered
in this paper. One of the latest recommendations for
the determination of trace amounts of ethyl diazo-
acetate considers the use of high-performance liquid
chromatography (HPLC) as a method that does not
require heating of samples [7].
For the same reason, the main analytical method in
the case of diazo compounds has become the mass-
spectrometry, because the transfer of the samples into
the gas phase at pressures less than 0.1–1.0 mm Hg
requires relatively low temperature. The database of
the National Institute of Standards and Technology
(NIST, USA) [8] includes the mass spectra of several
Unfortunately, the criteria of the stability of organic
compounds at the chromatographic analysis that
1675

1676
KORNILOVA et al.
tens of diazo compounds of different classes. The mass
spectrum of diazomethane in comparison with the
mass spectrum of the isomeric diazirine was analyzed
in detail as early as 1963 [9]. The spectra of the
simplest alkyl diazoacetates, including methyl diazo-
acetoacetate, dimethyl diazomalonate, and 3-diazo-
pentane-2,4-dione were considered in detail in [10],
cyclic 2-diazo-1,3-diketones, in [11]. The mass spectra
of many compounds of this class, like several α-
diazoketones [12], 3-diazo-1,4-diphenyl-4-hydroxy-
butan-2-one [13] and others, were not discussed
specifically, but included to the experimental sections
of the respective works on the organic synthesis. The
absence of thermal limitations at the registration of
mass spectra of diazo compound allowed the extension
of this method over the complex multifunctional
compounds of this class [14–17].
tion using standard polydimethyl siloxane stationary
phases was known only for ethyl diazoacetate (843±6).
It was estimated on the ground of the normal boiling
temperature of this compound (140–141ºC, according
to other sources 143ºC) and molar refraction index
using algorithm [18]. Estimation of the RI by additive
scheme [19] considered in the database [8] un-
fortunately turned out to be impossible for diazo com-
pounds.
This paper deals with chromatographic and gas
chromatography-mass spectrometric characterization,
especially with the stability under the conditions of
analysis, of diazocarbonyl compounds of two types:
alkyl diazoacetates Ia–Ig and diazomethylketones IIa–
IIe. As a rule, the samples for the study have not been
preliminarily purified, therefore we identified the
admixtures in the samples of diazo compounds. As the
admixtures, we detected alkyl chloroacetates III,
nitrites IV and nitrates V of glycolic acid alkyl esters,
“dimeric” products VI, and 1-chloroalkan-2-ones VII.
In the process of the chromatographic analysis we also
registered the formation of ketenes VIII as a result of
decomposition of the diazo compounds.
The most informative chromatographic charac-
teristic of organic compounds for their identification
are retention indices (RI), which are inter-laboratory
reproducible. However, such indices have not been
determined even for the simplest aliphatic diazo com-
pounds. Before the beginning of this work the RI evalua-
H
CH2Cl
RO2C CH2Cl
C
N2
R
III
RO2C
H
O
I
VII
CH2ONO
IV
CH2ONO2
V
RO2C
RO2C
R
C
N2
C
C O
R
H
VIII
O
II
X(CH2CO2R)2
VI
Preliminary discussion on the subject was reported
in [20, 21], where the experimentally determined gas
chromatographic RI for the diazo compounds were
first published.
unknown. Thus, the gas chromatographic analysis of
alkylazides is possible at temperatures at least up to
130–135ºC, which is sufficient for the simplest
representatives of this class [22, 23]. In a series like
alkyl hypochlorites ROCl the bp values at the
atmospheric pressure are known only for R = C3H7
(62.9ºC) and t-C4H9 (77–78ºC). Consequently, the
limit of thermal stability of the compounds of this class
is about 80ºC, which is clearly insufficient for their gas
chromatographic analysis. But even in this series the
RI values of ethyl (502) and tert-butyl hypochlorites
(605) have been experimentally determined.
As a criterion of the possibility of gas-chro-
matographic analysis of thermally unstable compounds
it is advisable to take the maximum values of the
boiling points (bp) of homologs of this class under the
atmospheric pressure. When the retention temperatures
exceed these temperatures the gas-chromatographic
analysis is impossible. An example comprises aliphatic
azides RN3 with the bp 20–21ºC (R = CH3), 48–50ºC
(C2H5), 77.5–78ºC (C3H7), 106.5ºC (C4H9) and 130–
135ºC (C5H11). For the azides with alkyl fragments
larger than C5H11 the bp at atmospheric pressure are
Among the aliphatic diazocarbonyl compounds one
of the most commonly used and most thoroughly
characterized by physical and chemical constants is
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STABILITY OF DIAZOCARBONYL COMPOUNDS
1677
ethyl diazoacetate [bp 140–143ºC; nD20 1.460 (1), d420
1.082(10); μ 2.03 D] (we failed to find bp values at the
atmospheric pressure for other alkyldiazoacetates).
Consequently, the gas chromatographic analysis of
diazocarbonyl compounds without their decomposition
is limited by the column temperature of approximately
140ºC.
lead to diffuse chromatographic peaks of individual
components.
(3) Thermal decomposition of the analytes directly
in the chromatographic column. Depending on the
nature of the process, in this case either complete
absence of signals in the chromatograms occurs, or, if
the original compounds and decomposition products
are sufficiently volatile, their peaks are recorded, but
the relative intensities vary widely, and between them
appear additional extensive diffuse peaks. Their
appearance is due to the occurrence of reactions in dif-
ferent parts of the chromatographic column at
components moving through it, and the degradation
products cannot be concentrated in the narrow chro-
matographic zones.
In a general case, at the gas-chromatographic
analysis of thermally unstable compounds at least three
pathways of their decomposition should be taken into
consideration .
(1) Thermal or catalytic decomposition prior to the
analysis, that is, directly in the reaction mixtures
during the isolation of target products, or at the storage
of the samples. It is believed that the main direction of
alkyl diazoacetates transformations is the formation of
diesters of (E)- and (Z)-but-2-enedioic acids [24].
However, the results of gas chromatography–mass
spectrometric analysis of the C1–C4 esters (see below)
has neither revealed the presence of the fumarate and
maleate (their RI are known). Nevertheless, in the
samples of such esters were found impurities with
unknown mass spectra, which could not be interpreted
using the database [8]. A similar conclusion about the
presence of unidentified impurities in the samples of
ethyl diazoacetate was published in [7]. The con-
clusion that these products were formed not during, but
before the chromatographic analysis, is based on the
fact that the ratio of peak areas of different
components remains practically constant despite
varying the analysis temperature.
Both the second and third cases of the thermal
instability were revealed in the analysis of diazo-
carbonyl compounds.
Alkyldiazoacetates Ia–Ig. Table 1 characterizes
seven simple alkyldiazoacetates N2CHCO2R (I) with
R = Me (Ia), Et (Ib), Pr (Ic), i-Pr (Id), Bu (Ie), i-Bu
(If) and t-Bu (Ig). The data include retention tem-
peratures (mode A), the retention indices for the phase
HP-5 with 5% of phenyl groups, evaluation of their RI
on the dimethylsiloxane stationary phases not
containing phenyl groups, as well as standard (70 eV)
mass spectra. The full mass spectra are also given. The
mass spectra of the compounds Ia [8] and Ib [8, 10]
have been pulished earlier.
In the selected conditions of chromatographic
separation of the alkyl diazoacetates C1–C4 the
retention temperature (TR) is as low as 54–87ºC, which
is significantly less than the limit of their estimated
thermal stability (~140ºC). Hence, for all the esters the
thermal decomposition in the analysis can be
neglected. However, for the higher homologues of this
series the retention temperature will naturally be
higher. Relation (1) (experimental part) allows us to
estimate the maximum size of the alkyl radical R
corresponding to the TR comparable with the limit of
thermal stability of the corresponding compound. For
butyl diazoacetate Ie the RI is 1058, hence, the
estimated RI for the ester with R = C8H17 is ~(1058 +
400) = 1458, which corresponds to the retention time
~20.3 min, and the value of TR ~142ºC. For the
analysis of such ester it is necessary to use a shorter
chromatographic column and a “soft” option of tem-
perature programming.
(2) Thermal decomposition or isomerization of the
components of the analyzed samples in the chro-
matograph injector at the dosing. Such processes could
theoretically be detected by varying the temperature of
the injector, but in the optimal case, it is desirable to
suppress them completely. However, if a high degree
of conversion occurs over a wide temperature range,
their identification can be a rather difficult task.
Examples of such instability are the isomerization of
dimethyl
(Z)-4-diazopent-2-enedioate
into
the
corresponding pyrazole and the decomposition of
dimethyl (E)-4-diazo-3-(trifluoromethyl)pent-2-ene-
dioate with the removal of the nitrogen molecule and
the formation of dimethyl cyclopropenedicarboxylate
[20, 21]. For this reason, the gas chromatographic
analysis of diazocarbonyl compounds was carried out
at the injector temperature not higher than 100ºC. The
value of 77ºC, used in [7], is too small, and may
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KORNILOVA et al.
Table 1. Retention temperatures (TR), retention indices (RI), and standard mass spectra (70 eV) of alkyldiazoacetates
N2CHCO2R (I)
Comp.
no.
R
M
TR, °C
RI а
Mass-spectrum, m/z ≥ 40 (Irel ≥ 2%)
Me
100
54
784±5a
757±8
101 (4), 100 (100) [M], 72 (2) [M – N2], 70 (2), 69 (78) [N2CHCO], 59 (4), 44 (3),
43 (23), 42 (10), 41 (51) [CHCO], 40 (3)
Ia
Et
Pr
114
128
62
73
867±2а
115 (5), 114 (82) [M], 86 (9) [M – N2], 70 (3), 69 (100) [N2CHCO], 68 (2), 58 (15),
Ib
Ic
840±4
57 (9), 45 (8), 44 (3), 43 (11), 42 (19), 41 (39) [CHCO], 40(2)b
834±6 [8]
959±2а
931±4
128 (14) [M], 100 (2) [M – N2], 99 (2), 87 (24) [N2CHC(OH)2], 86 (5), 70 (2), 69 (58)
[N2CHCO], 59 (4), 58 (6), 57 (3), 56 (3), 55 (5), 54 (2), 44 (4), 43 (100) [C3H7],
42 (18), 41 (80) [CHCO], 40 (3)
i-Pr
128
142
66
87
902±1а
875±4
1058±1а
1031±4
128 (19) [M], 87 (3), 86 (3), 69 (47) [N2CHCO], 59 (5), 55 (2), 45 (2), 44 (4), 43 (100)
Id
Ie
[C3H7], 42 (11), 41 (44) [CHCO], 40 (2)
Bu
142 (3) [M], 114 (4) [M – N2], 113 (2), 101 (6), 99 (3), 87 (26) [N2CHC(OH)2], 86 (4),
73 (3), 72 (2), 71 (2), 70 (2), 69 (47) [N2CHCO], 68 (2), 59 (2), 58 (5), 57 (51) [C4H9],
56 (34), 55 (22), 54 (2), 53 (2), 44 (4), 43 (12), 42 (16), 41 (100) [CHCO], 40 (3)
i-Bu
t-Bu
142
142
81
71
1015±1а
988±4
142 (3) [M], 99 (5), 88 (2), 87 (58) [N2CHC(OH)2], 86 (2), 73 (2), 71 (2), 70 (4),
69 (100) [N2CHCO], 59 (5), 57 (62) [C4H9], 56 (40), 55 (10), 53 (2), 44 (2), 43 (25),
42 (13), 41 (95) [CHCO], 40 (3)
If
940±2а
913±4
142 (0.3) [М], 70 (5), 69 (68) [N2CHCO], 68 (2), 67 (5), 57 (4), 54 (3), 53 (10), 51 (3),
43 (5), 42 (5), 41 (100) [CHCO], 40 (3)
Ig
a
The retention indices determined in the A mode on a column with the phase HP-5, the second value corresponds to the RI estimate on the
polmethylsiloxane phases not containing phenyl groups. The average difference <ΔRI> = 27±4. b At the registration of mass-spectrum of
ethyl diazoacetate , in the region of m/z ≥ 25 the maximum signal (m/z)100 is at 29 units (Et)
Raising the temperature of analysis of the
synthesis. In all alkyl diazoacetates there are the
admixtures of the corresponding alkyl chloroacetates
IIIa, IIIc–IIIf with shorter retention time (mean value
of ΔRI is –25±3). Among the components with high
retention times the compounds should be noted with
the characteristic mass spectra that are not re-
cognizable using the database [8], that is, not
belonging to the class represented in the database. The
mass spectra contain, along with the expected peaks of
alkyl fragments [R]+, rather intense peaks with m/z 46
and 76, typical of alkyl esters of nitric acid and
belonging to the ions [NO2]+, and [CH2ONO2]+,
respectively. As far as their RI also vary in line with
the RI values of alkyl diazoacetates (average ΔRI is
112±8, Table 2), they can be unambiguously identified
as the alkyl esters of glycolic acid nitrate
O2NOCH2CO2R (Va, Vb, Vd, Vf), in a quite notable
amount. For example, the sample If contained the
isobutyl ester of glycolic acid nitrate in an amount
comparable with the isobutyl diazoacetate (Fig. 1).
alkyldiazoacetates leads to a complete absence in the
chromatograms of the peaks of both the esters and the
possible products of their decomposition. However, the
peaks were detected of the degradation products of the
column stationary phase due to its interaction with the
products of decomposition of the analytes.
Mass spectra of the diazo esters are fully consistent
with the known patterns of their fragmentation [8, 10].
In all cases the peaks of molecular ions were recorded
that are visible even in the case of R = t-C4H9, due to
the presence of the conjugated system CO–CH=N+=N–
in the molecules. The characteristic fragment ions are
[M – 28] = [M – N2]+•, [M – RO]+ = [N2CHCO]+ (m/z
69), [M – N2–RO]+ = [CHCO]+ (m/z 41) and, if R ≥
C3H7, then [N2CHC(OH)2]+ (m/z 87, the result of the
so-called “double” hydrogen rearrangement).
Identification of impurities in alkyl diazo-
acetates. At the temperature below 140ºC there are no
indications of the decomposition of diazocarbonyl
compounds in the course of chromatographic analysis,
hence, all the detected components with the mass
spectra and RI listed in Table 2 have formed during the
Formation of such esters is possible due to the
presence of uncontrolled amounts of nitrate in the
sodium nitrite (XN2+ + NO3– → XONO2 + N2), as well
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STABILITY OF DIAZOCARBONYL COMPOUNDS
1679
Table 2. Retenion indices RI and standard mass-spectra (70 eV) of impurities in the reaction mixtures at the synthesis of
alkyl diazoacetates N2CHCO2R
Comp.
no.
RI
R
М
Mass-spectrum, m/z ≥ 40 (Irel ≥ 2%)
Alkyl chloroacetates ClCH2CO2R (III)
(A mode)
Me
Et
108
122
763±2
839±2
110 (3), 108 (9) [M], 79 (9), 78 (2), 77 (27) [M – CH3O], 76 (3), 66 (5), 64 (17), 60 (2),
59 (100) [CO2CH3], 51 (15), 50 (2), 49 (45) [СН2Cl], 48 (4), 47 (2), 45 (3), 42 (11)
IIIa
IIIb
122 (2) [M], 109 (2), 107 (6), 97 (2), 96 (7), 95 (7), 94 (22) [M – C2H4], 79 (33), 78 (4),
77 (100) [M – C2H5O], 76 (4), 73 (5), 60 (4), 51 (17), 50 (3), 49 (51) [СН2Cl], 48 (5), 47 (2),
45 (15), 44 (2), 43 (17), 42 (51), 41 (14)
Pr
136
933±1
136 (0) [M], 109 (3), 107 (9), 97 (7), 95 (23) [M – C3H5], 79 (17), 78 (2), 77 (53) [M –
– C3H7O], 76 (2), 76 (2), 60 (2), 59 (4), 57 (8), 51 (7), 49 (21) [СН2Cl], 43 (100) [C3H7],
42 (42), 41 (39), 40 (2)
IIIc
i-Pr
136
150
880±1a
850±4
136 (0) [М], 123 (7), 121 (23), 97 (2), 95 (5), 85 (2), 79 (20), 78 (2), 77 (62), 59 (8), 51 (5),
49 (16) [СН2Cl], 45 (7), 44 (4), 43 (100), 42 (15), 41 (26)
IIId
IIIe
Bu
1032±2
150 (0) [M], 109 (2), 107 (5), 95 (6), 79 (13), 78 (2), 77 (38) [M – C4H9O], 76 (2), 73 (2),
71 (2), 60 (2), 58 (3), 57 (74), 56 (100), 55 (14), 51 (6), 49 (17) [СН2Cl], 43 (11), 42 (13),
41 (65), 40 (2)
i-Bu
150
988±1a
964±11
150 (0) [М], 110 (4), 109 (5), 108 (13), 107 (8), 79 (17), 78 (2), 77 (54), 76 (3), 72 (3),
71 (6), 59 (4), 58 (3), 57 (56), 56 (100), 55 (7), 51 (6), 49 (16) [СН2Cl], 44 (2), 43 (40),
42 (20), 41 (49), 40 (2)
IIIf
Ethyl nirosooxyacetate ONOCH2CO2Et (IVb) and alkyl nitrooxyacetates (V)
Et
133
135
149
163
177
904±2
133 (0) [M], 105 (6), 104 (6), 88 (2), 87 (57) [M – NO2], 76 (4), 73 (2), 61 (7), 60 (100)
IVb
Va
Vb
Vd
Vf
[ONOCH2], 59 (26), 58 (2), 57 (2), 45 (19), 44 (2), 43 (9), 42 (2), 41 (2)
Me
Et
908±2
135 (0) [М], 77 (4), 76 (38) [O2NOCH2], 60 (3), 59 (92) [CO2CH3], 46 (100) [NO2], 45 (23),
44 (6), 43 (2), 42 (4)
977±2
149 (0) [М], 106 (2), 90 (4), 76 (51) [O2NOCH2], 61 (2), 60 (2), 59 (2), 57 (4), 46 (100)
[NO2], 45 (15), 44 (8), 43 (10), 42 (6)
i-Pr
i-Bu
1010±2
1120±2
163 (0) [M], 148 (2), 104 (2), 90 (25), 76 (13) [O2NOCH2], 59 (2), 46 (56) [NO2], 45 (7),
44 (5), 43 (100) [C3H7], 42 (5), 41 (24)
177 (0) [M], 116 (1), 104 (2), 76 (32) [O2NOCH2], 61 (7), 59 (3), 58 (6), 57 (100) [C4H9],
56 (51), 55 (7), 46 (53) [NO2], 44 (5), 43 (50), 42 (11), 41 (74), 40 (2)
Dimeric compounds X(CH2CO2R)2 (VI)
Pr
245
245
271
271
1696±3
1586±4
1869±5
1573±4
172 (2), 159 (14), 141 (2), 130 (11), 100 (2), 97 (2), 84 (2), 73 (2), 70 (2), 59 (4), 57 (2),
55 (3), 54 (12), 53 (5), 44 (15), 43 (100), 42 (37), 41 (33), 40 (2)
VIc
VId
VIe
VIg
i-Pr
Bu
172 (4), 157 (3), 155 (2), 130 (16), 100 (2), 69 (2), 59 (3), 53 (3), 45 (7), 44 (5), 43 (100),
42 (3), 41 (16)
186 (1), 159 (14), 130 (6), 98 (2), 73 (4), 70 (2), 58 (4), 57 (100), 56 (71), 55 (16), 54 (10),
53 (5), 52 (2), 45 (2), 44 (15), 43 (24), 42 (7), 41 (75), 40 (3)
t-Bu
130 (4), 58 (4), 57 (100), 56 (6), 55 (3), 53 (3), 439 (7), 42 (2), 41 (29)
a
The retention indices determined in the A mode on a column with the phase HP-5, the second value corresponds to the RI estimate on the
polyvinylsiloxane phases not containing phenyl groups. The average difference <ΔRI> = 27±4.
as more complex processes involving the inter-
mediately forming diazonium cations. It was found for
example that reaction of diazo compounds YCHN2
with N2O5 results not only in nitro compounds
YC(NO2)N2, but also in the formation of the
corresponding nitrates YCH2ONO2 [25].
If the main impurities in alkyl diazoacetates ob-
tained from the corresponding amine hydrochloride
and sodium nitrite are the esters of nitric acid, it is
natural to expect the presence in some amount of the
esters of nitrous acid XONO. However, such ester IVb
was found only in the sample Ib, whose mass
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KORNILOVA et al.
This scheme can be transformed to estimate the RI
of compound XMe2 (for ethane, RI = 200):
XMe2 = X(CH2CO2R)2 – ROCOCH2CH2CO2R + C2H6.
Then, according to the data for the impurities in
various alkyldiazoacetats, we get the average RI value
537±4 for XMe2.
R
X(CH2CO2R)2 ROCOCH2CH2CO2R
MeXMe
540
Pr
1696±3
1586±4
1869±5
1573±4
1356±12
1248±8
1531±4
1242±4
i-Pr
Bu
538
538
t-Bu
531
Retention time, min
Fig. 1. The chromatogram of the reaction mixture contain-
ing isobutyl diazoacetate If (A mode). The peak with the
retention time 7.41 min corresonds to isobutyl chloroacetate,
8.19 min, to isobutyl diazoacetate, 11.18 min, to isobutul
ester of glycolic acid nitrate O2NOCH2CH2CH(CH3)2.
Based on literature data and additive ratios, we
calculated RI for the following compounds with the
formula XMe2: X = O (327±8), N=N (396±4), N(O)=N
(615±19), >N–NO (708±5) and NH–N=N (529±11).
Thus, the best correspondence with the experimental
value of RI was observed for 1,3-dimethyltriazene
MeNHN=NMe. An estimate of the RI for it is made on
the basis of bp (50.8°C) and the molar refraction using
the algorithm [18].
The structural fragment –CO–CH=N+=N– of diazo-
carbonyl compounds is polar, therefore their RI, deter-
mined on a polydimethylsiloxane phases containing
5% of phenyl groups and without the latter are
noticeably different. The average value of difference of
the indices is 27±4, so the Table 1 comprises two sets
of data.
spectrum contains the peaks characteristic of alkyl
nitrite ion [CH2ONO]+ with m/z 60.
In the samples of alkyl diazoacetates Ic–Ie, Ig
besides the above considered impurities more complex
components VIc–VIe, VIg were detected in varied
amounts, which are not esters of (E)- or (Z)-but-2-
enedioic acids. Their mass spectra and RI are given in
Table 2. Their mass spectra do not contain the peaks of
molecular ions, but include the peaks of the ions with
the m/z 130, and the maximum peaks confirm the
presence of alkyl fragments R.
The RI values of compounds IV allows to assume
the presence in the molecule of two structural
fragments CH2CO2R, that is, they have the general
formula X(CH2CO2R)2. This follows from the fact that
commonly in going from propyl to butyl esters (R = Pr
and Bu, respectively) the RI values of alkyl
diazoacetates I, chloroacetates III, and nitroglycolates
increase approximately by 100 index units, while for
the component under consideration, by about 200
index units (Table 2). A more detailed analysis of RI,
given a similarity of the mass spectra, suggests that
they belong to the same series (X = const). To reveal
the nature of the X fragment the additive scheme of RI
evaluation can be used, based on a hypothetical
“assembling” structures of complex molecules from
simpler ones. In this case a structural analogy of
diesters X(CH2CO2R)2 and the known diesters of
butandioic acid ROCOCH2CH2CO2R is of interest:
α-Diazoketones. Table 3 shows the mass spectra
and retention indices of aliphatic α-diazoketones
RCOCHN2, R = Pr (IIa), i-Pr (IIb), n-C5H11 (IIc), i-
C5H11 (IId) and n- C9H19 (IIe), and three phenyl-
substituted diazoketones Ph(CH2)nCOCHN2 with n = 0
(IIf), 1 (IIg) and 2 (IIh). The retention temperatures of
aliphatic diazoketones (IIa–IIf) in D mode are in the
range of 59–137°C. However, even the last of these
values (for R = n-C9H19) does not exceed the limit of
thermal stability of diazocarbonyl compounds (~140°C),
since there are no indications of the decomposition of
diazoketones in the course of chromatographic
separation. If the temperature rise is programmed with
a higher rate (Mode C: 70°C, 10°C min–1), the diazo-
ketones are decomposed in the chromatographic
column completely (aliphatic) or partially (aromatic).
In all cases, the products are substituted ketenes VIII,
formed through the Wolf rearrangement [26]. The first
recorded mass spectra of ketenes are shown in Table 3,
ROCOCH2XCH±2CO2R = ROCOCH2CH2CO2R
+ MeXMe – C2H6.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 82 No. 10 2012

STABILITY OF DIAZOCARBONYL COMPOUNDS
1681
Table 3. Retention temperatures (TR), retention indices (RI), and standard mass spectra (70 eV) of diazomethyl ketones
RCOCHN2 (II) as well as the impurities in the reaction mixtures
TR, °C
Compound
М
RI
Mass-spectrum, m/z ≥ 39 (Irel ≥ 2%)
(mode)
59 (D)
54 (D)
84 (D)
Diazoketones II
1-Diazopentan-2-one,
112
112
140
957±2а 113 (2), 112 (22) [М], 85 (3), 84 (79) [М – N2], 71 (24), 70 (2), 69 (46) [M –
930±4 C3H7=N2CHCO], 57 (2), 56 (15), 55 (100), 54 (2), 53 (6), 51 (2), 50 (2),
44 (3), 43 (75), 42 (26), 41 (66) [CHCO], 40 (6), 39 (32)
918±2а 113 (2), 112 (40) [M], 84 (28) [М – N2], 83 (8), 71 (7), 70 (4), 69 (66) [M –
889±4 C3H7], 68 (2), 56 (12), 55 (16), 53 (5), 51 (3), 50 (2), 44 (2), 43 (81),
42 (24), 41 (100) [M – C3H7 – N2=СНСО], 40 (6), 39 (41)
1157±2а 140 (0.6) [М], 112 (11) [M – N2], 99 (3), 97 (5), 94 (3), 85 (2), 84 (47) [M –
1130±4 C4H8], 83 (16), 79 (3), 71 (11), 70 (9), 69 (36) [M – C5H11=N2CHCO],
67 (5), 58 (4), 57 (4), 56 (23), 55 (100), 54 (2), 53 (4), 44 (2), 43 (55),
42 (26), 41 (51) [M – C5H11 – N2=СНСО], 40 (4), 39 (20)
IIa
1-Diazo-3-
methylbutan-2-one,
IIb
1-Diazoheptan-2-one,
IIc
1-Diazo-5-
methyldеcan-2-one,
IId
140
196
75 (D)
1083±2а 140 (0.1) [М], 112 (47) [M – N2], 84 (14), 83 (100) [M – C4H9], 81 (5),
1056±4 71 (27), 70 (10), 69 (15), 65 (6), 59 (2), 55 (97), 54 (6), 53 (13), 51 (7),
43 (49), 42 (23), 41 (44) [M – C5H11 – N2=СНСО], 40 (9), 39 (29)
1564±3а 196 (0.1) [М], 139 (2), 125 (3), 112 (9), 111 (9), 99 (4), 98 (58), 97 (40),
1537±5 96 (3), 95 (7), 94 (2), 93 (3), 85 (5), 84 (48) [M – C8H16], 83 (61), 82 (18),
81 (10), 80 (2), 79 (5), 71 (11), 70 (28), 69 (32) [M – C9H19=N2CHCO],
68 (13), 67 (13), 59 (2), 58 (6), 57 (17), 56 (24), 55 (100), 54 (12), 53 (5),
44 (2), 43 (53), 42 (17), 41 (55) [M – C9H19 – N2=СНСО], 40 (3), 39 (14)
1-Diazoundecan-2-
one, IIe
137 (D)
Diazoacetophenone,
146
160
174
84 (B)
170 (C)
112 (D)
1359±1а 147 (4), 146 (43) [М], 119 (2), 118 (21) [M – N2], 106 (4), 105 (53)
1304±1 [C6H5CO], 91 (7), 90 (100) [M – N2 – CO], 89 (74) [M – N2 – CHO], 78 (3),
77 (47) [C6H5], 76 (2), 75 (3), 74 (4), 73 (2), 64 (11), 63 (25), 62 (8), 61 (3),
59 (3), 52 (2), 51 (25), 50 (13), 49 (2), 45 (6), 43 (2), 41 (2), 40 (3), 39 (13)
1407±1а 160 (<0.1) [М], 133 (3), 132 (31) [M – N2], 105 (10), 104 (100) [M – N2 –
1350±1 CO], 103 (43) [M – N2 – CHO], 102 (6), 92 (9), 91 (99) [C6H5CH2], 90 (2),
89 (7), 79 (2), 78 (36), 77 (29), 76 (4), 75 (3), 74 (4), 69 (19), 66 (3), 65 (28),
64 (2), 63 (12), 62 (4), 55 (6), 52 (8), 51 (30), 50 (11), 41 (6), 39 (19)
1516±1а 174 (0.4) [М], 147 (4), 146 (32) [M – N2], 145 (13), 131 (9), 129 (3), 128 (4),
1453±1 127 (12), 119 (6), 118 (64) [M – N2 – CO], 117 (46) [M – N2 – CHO],
116 (7), 115 (20), 105 (17), 104 (73) [C6H5CHCH2], 103 (19), 102 (3),
92 (8), 91 (100) [C6H5CH2], 90 (11), 89 (9), 79 (8), 78 (19), 77 (22), 76 (3),
75 (2), 74 (2), 69 (6), 66 (2), 65 (38), 64 (3), 63 (11), 62 (3), 57 (5), 56 (2),
55 (77), 53 (2), 52 (5), 51 (21), 50 (7), 41 (7), 40 (2), 39 (21)
IIf
1-Diazo-3-
phenylpropan-2-one,
IIg
90 (B)
– (>175) (C)
118 (D)
1-Diazo-4-
phenylbutan-2-one,
IIh
102 (B)
– (>181) (C)
145 (D)c
1-Chloroalkane-2-ones VII
1-Chloropentan-2-
120
148
(D)
(D)
878±3а 120 (2) [М], 79 (2), 77 (5), 72 (3), 71 (54) [M – CH2Cl], 51 (2), 49 (7)
one, VIIa
851±5 [CH2Cl], 44 (3), 43 (100) [C3H7], 42 (9), 41 (32), 39 (8)
1-Chloroheptan-2-
one, VIIc
1077±1а 148 (1) [М], 100 (4), 99 (48) [M – CH2Cl], 94 (4), 93 (2), 92 (11) [M –
1050±4 C4H8], 81 (2), 79 (2), 77 (5), 72 (4), 71 (66) [C5H11], 65 (2), 60 (2), 58 (2), 57
(4), 56 (4), 55 (9), 51 (2), 49 (6) [CH2Cl], 44 (4), 43 (100) [C3H7], 42 (8), 41
(18), 39 (8)
1-Chloroundecan-2-
204
154
(D)
1483±2а 204 (1) [М], 174 (2), 156 (9), 155 (64) [M – CH2Cl], 153 (2), 150 (2), 138
1456±4 (2), 137 (5), 129 (2), 124 (2), 110 (2), 105 (3), 100 (2), 99 (2), 98 (2), 97 (4),
96 (2), 95 (30), 94 (5), 93 (6), 92 (13) [M – C8H16], 85 (35), 84 (5), 83 (7),
82 (2), 81 (26), 79 (4), 77 (5), 72 (5), 71 (68), 70 (10), 69 (18), 68 (6),
67 (13), 59 (5), 58 (18), 57 (53), 56 (4), 55 (25), 54 (2), 53 (3), 49 (5),
44 (11), 43 (100) [C3H7], 42 (12), 41 (47), 39 (8)
one, VIIe
2-Chloro-
acetophenone, VIIf
(B), (C), (D)
1274±2а 154 (1) [M], 106 (6), 105 (100) [M – CH2Cl], 91 (4), 78 (4), 77 (54), 75 (2),
1222±1 74 (3), 65 (3), 63 (2), 52 (2), 51 (28), 50 (12), 49 (3)
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 82 No. 10 2012

1682
KORNILOVA et al.
Table 3. (Contd.)
Compound
TR, °C
(mode)
М
RI
Mass-spectrum, m/z ≥ 39 (Irel ≥ 2%)
1-Chloroalkane-2-ones VII
3-Phenyl-1-
chloropropan-2-one,
VIIg
168
182
(B), (C), (D)
(B), (C), (D)
1314±2а 170 (3), 168 (9) [М], 131 (2), 119 (12) [M – CH2Cl], 92 (7), 91 (100)
1260±1
[C6H5CH2], 77 (4), 65 (14), 63 (5), 52 (2), 51 (7), 50 (3), 49 (3), 46 (2),
44 (4), 41 (2)
4-Phenyl-1-
chlorobutan-2-one,
VIIh
1432±2а 184 (6), 183 (2), 182 (18) [М], 147 (2), 146 (4), 134 (4), 133 (47) [M –
1377±1
CH2Cl], 129 (5), 127 (2), 125 (3), 115 (2), 106 (9), 105 (98) [M – CH2Cl –
CO], 104 (12), 103 (11), 102 (2), 92 (7), 91 (100) [C6H5CH2], 89 (2), 79 (14),
78 (8), 77 (21), 66 (2), 65 (12), 63 (3), 55 (5), 52 (2), 51 (13), 50 (3),
48 (4), 43 (3), 41 (2), 39 (6)
1-Phenyl-3-
chlorobutan-2-one,
VIIi
182
(B), (C)
1370±1а 184 (4), 183 (2), 182 (13) [М], 148 (4), 147 (48) [M – Cl], 146 (2), 133 (8),
1314±4
131 (4), 129 (5), 128 (2), 126 (2), 119 (2), 118 (3), 117 (15), 116 (9), 115
(22), 106 (5), 105 (33), 104 (5), 103 (9), 102 (2), 92 (7), 91 (100) [C6H5CH2],
89 (4), 79 (4), 78 (3), 77 (7), 75 (2), 73 (2), 65 (16), 64 (2), 63 (5), 55 (2),
53 (2), 52 (2), 51 (8), 50 (3), 49 (2), 43 (2), 41 (2), 39 (9), 38 (2)
Ketenes VIIIb
Pent-1-en-1-one,
84
112
132
(C)
(C), (D)
(C)
–
–
–
84 (21) [М], 56 (7), 55 (100) [M – C2H5], 53 (3), 51 (2), 50 (3), 42 (3),
41 (13)
VIIIa
Hept-1-en-1-one,
VIIIb
112 (8) [М], 94 (3), 84 (5), 83 (5), 70 (4), 69 (11), 68 (18), 67 (3), 57 (3),
56 (19), 55 (100) [M – C4H9], 53 (2), 43 (7), 42 (14), 41 (33)
3-Phenylprop-1-en-
1-one, VIIIg
133 (13), 132 (100) [М], 131 (85) [M – H], 105 (10), 104 (53) [M – CO],
103 (90) [M – CHO], 102 (11), 98 (2), 92 (2), 91 (27), 89 (5), 81 (5), 79 (4),
78 (46), 77 (38), 76 (11), 75 (5), 74 (7), 66 (2), 65 (10), 63 (12), 62 (5), 61
(5), 57 (3), 56 (2), 55 (21), 52 (22), 51 (63), 50 (30), 49 (3), 44 (18), 41 (9)
4-Phenylbut-2-en-1-
one, VIIIh
146
(C)
–
147 (3), 146 (26) [М], 118 (10), 115 (5), 92 (3), 91 (36) [C6H5CH2], 89 (2), 77
(2), 65 (11), 63 (4), 57 (3), 56 (3), 55 (100) [M – C6H5CH2], 51 (7), 50 (3), 41
(2)
a
Retention indices, determined in modes А, C, D on the columns for the phase with 5% of phenyl groups, second value RI is for the
dimethylsiloxane stationary phases not containing phenyl groups (mode B); average value <ΔRI>: 27±4 (aliphatic compounds), 56±4
b
(phenyl-substituted compounds). Substituted ketenes formed at relative high temperatures as the decomposition products of
c
diazocompounds in chromatographic column and registered as diffuse peaks, the calculation of retention indices is impossible. Partial
decomposition is observed at TR = 145°С (see a fragment of the chromatogram, Fig. 2).
but their RI cannot be determined, because these
products are formed during the separation and provide
a broad diffuse peaks.
bonds) is stable, while the other two decompose com-
pletely. In this case in none of the modes even traces of
phenylketene could be detected.
Retention temperature (TR) of phenyl-substituted
diazoketones IIe–IIh are 84–102°C in B mode and
112–145°C in D mode, so that in the B mode the
thermal decomposition is not observed. In the case of
4-phenyl-1-diazobutan-2-one IIIh at TR = 145°C indica-
tions appear of the partial decomposition, as illustrates
the chromatogram fragment shown in Fig. 2. This fact
once again confirms the correctness of the assessment
of thermal stability of the diazocarbonyl compounds in
gas chromatograpic analysis (~140°C). As to the
“hardest” C mode with TR of aryldiazoketones 170–
180°C, only the simplest of them (diazoacetophenone
PhCOCHN2 IIe, which has a system of conjugated
The expected impurities in all of diazoketones, like
in the diazoesters, are 1-chloro-substituted alkane-2-
ones VIIa–VIIh formed in the synthesis of diazo-
ketones, which were detected only in the sereies of
IIe–IIh. For instance, in a sample of 1-diazo-3-
phenylpropan-2-one there is a component with a mole-
cular mass of 182 and RI 1370 (Mode C), containing
one chlorine atom in the molecule (the relative
intensity of the peaks at m/z 182 and 184 is ~3:1) and a
fragment of PhCH2 (maximum signal with m/z 91),
which is the formal homolog of “normal” 3-phenyl-1-
chloropropan-2-one. As a result of a joint inter-
pretation of mass spectrometric and chromatographic
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 82 No. 10 2012

STABILITY OF DIAZOCARBONYL COMPOUNDS
information, among several alleged versions of its
1683
structure could be selected only one, the 1-phenyl-3-
chlorobutane-2-one. Estimates of its RI by different
independent ways are close to the experimental value.
The retention index of 1-phenyl-3-chlorobutane-2-
one VIIk can be estimated on the basis of reference
values of RI of 1-phenylbutan-2-one (1228±11) and
the increment of the of H → Cl substitution in the α-
position to the carbonyl group (117±8 ) [27]:
C6H5CH2COCH2CH3 → C6H5CH2COCH(Cl)CH3,
(1228±11) + (117±8) = (1345±14).
The second way of estimating the RI is based on the
transformation of the methyl group in the structure of
3-chlorobutane-2-one in the group C6H5CH2 (ΔRI =
643±13 [28]):
CH3COCH(Cl)CH3 → C6H5CH2COCH(Cl)CH3,
Retention time, min
(704±3) [27] + (643±13) = (1347±13).
Adding to these two values the result of applying
the algorithm of RI prediction based on an assessment
of its boiling point (255.3±20°C, ACD software) and
molar refraction [18], which gives a value of 1345±15,
we obtain the overall average value 1346±14
satisfactorily corresponding to the experimental value
of RI 1370±1 (Table 2). In addition, differences in the
mass spectra of ion series [29] of 1-phenyl-3-
chlorobutan-2-one and isomeric 4-phenyl-1-chloro-
butan-2-one (an impurity in 4-phenyl-1-diazobutan-2-
one) are quite acceptable (D = 31) to recognize these
compounds as belonging to the same homologous
series of chloro-substituted nonconjugated arylal-
kanones. The origin of the appearance of this
component in the reaction mixture remains unknown.
Fig. 2. A fragment of the chromatogram of 1-diazo-4-
phenylbutan-2-one (D mode, TR 145°C): retention time
46.3 min corresponds to 1-chloro-4-phenylbutan-2-one, the
main peak (51.5–52.3 min) to 1-diazo-4-phenylbutan-2-
one, 58.7 relates to a nonidentified component. The tail
before the main peak is due to the partial decomposition of
the diazo compound in the column with the formation of 4-
phenylbut-1-en-1-one (its mass spectrum is listed in Table 3).
(m/z 91). The common pathway in the fragmentation,
regardless of the presence or absence of the system of
conjugation, is a sequence M+• → [M – N2]+• → [M – N2 –
CO]+• and [M – N2 – CHO]+.
EXPERIMENTAL
Alkyl diazoacetates (I) were synthesized according
to general procedure [30]. To an aqueous solution of
alkyl (C1–C4) aminoacetate hydrochloride (20–40 mmol)
was added 10–15 ml of methylene chloride and the
mixture was cooled to –5°C. In an argon atmosphere at
stirring was added aqueous solution of NaNO2
(~1.2 molar excess). The mixture was then cooled to
approx. –10°C, 5% solution of sulfuric acid was added
dropwise to it, and the stirring was continued for
another 10–15 min. The organic layer was separated,
washed three times with saturated solution of sodium
bicarbonate and water, and dried over anhydrous
Na2SO4.
As in the case of alkyl diazoacetates, Table 3 shows
for each compound two RI values, for nonpolar
polydimethylsiloxane phase and the phase containing
5% of phenyl groups. For the diazoketones the average
difference <ΔRI> can be taken the same as for alkyl
diazoacetates (27±4), but for the aryl-substituted
ketones it is larger (56±4).
In the mass spectra of aliphatic diazoketones there
are strong peaks of molecular ions. Characteristic
fragmentation ions are [M – 28] = [M – N2]+•, [M – R]+ =
[N2CHCO]+ (m/z 69), [M – N2 – R]+ = [CHCO]+
(m/z 41) and, if R ≥ C5H11, then [M – CnH2n]+•`
(McLafferty rearrangement). Characteristic feature of
the nonconjugated phenyl-substituted diazoketones is
low intensity of the peaks of molecular ions (< 0.1–
0.4%) and a high intensity of the ions [C6H5CH2]+
Diazomethyl ketones (II) were synthesized
according to general procedure [31] from acyl
chlorides, synthesized in turn from the corresponding
carboxylic acids and thionyl chloride [32]. Ether
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 82 No. 10 2012

1684
KORNILOVA et al.
solution of an acid chloride (0.3–0.7 mmol) was added
dropwise with stirring to ether solution of diazo-
methane (molar excess 20 to 30%), and the mixture
was cooled in ice bath. The stirring was continued for
another 20–30 min, and then the diazomethane excess
was removed by a flow of argon.
C. On a Shimadzu QP 5000 chromatograph–mass
spectrometer using WCOT quartz column with a phase
HP-5 MSI (polydimethylsiloxane, 5% of phenyl
groups), length 25 m, internal diameter 0.20 mm (film
thickness of stationary phase 0.25 μm) in the mode of
temperature programming from 70°C to 280°C at a
rate 10°C min–1. The carrier gas (helium) linear
velocity 40 cm s–1, the evaporator temperature 100°C,
split ratio 1:180.
The 1-diazopentan-2-one (IIa) and 1-diazoheptan-
2-one (IIc) preparations contained a little (2–3%) of
isomeric 1-diazo-3-methylbutan-2-one (IIb) and 1-di-
azo-3-methylhexan-2-one (IId), respectively, with
respective lower RI values. The chromatographic
analysis (B mode) of the source carboxylic acids in the
form of butyl esters obtained from the corresponding
acid chlorides with 1-butanol (chemically pure for
chromatography grade) showed the presence of 2–3%
of the impurities of isomeric acids. The butyl butyrate
sample (RI 987±2, reference value 976±9) contained a
component with RI 945±2 (corresponds to the
reference value for butyl isobutyrate, 936±7). In the
sample of butyl caproate (1178±2, 1166±7) butyl
isocaproate (1149±2, 1138±7) was detected. Mass
spectra of these isomers are practically identical.
D. On a Shimadzu QP 2010 plus gas chro-
matograph–mass spectrometer using WCOT quartz
column with a phase HP-5 MSI (polydimethylsiloxane,
5% phenyl groups), length 30 m, internal diameter
0.25 mm (film thickness of stationary phase 0.25 μm)
in the mode of temperature programming from 40°C to
200°C at a rate 2°C min–1. The carrier gas (helium)
linear rate 51 cm s–1, the evaporator temperature 100°C,
split ratio 1:200.
The samples (1 μl of solution) were dosed with
appropriate split ratio, evaporator temperature did not
exceed 100°C. Since the analysis was performed with
temperature programming, the retention temperature
(TR) of different diazo compounds determined by the
relation (1) were different in the A–D modes:
Solutions of diazo compounds in methylene chlo-
ride or diethyl ether were analyzed without an
additional treatment, but after approximately 100 times
dilution with the same solvent. To characterize the
stability of diazo compounds in the conditions of gas
chromatographic separation, their analysis was
performed on different instruments, different columns
and at different temperatures:
TR ≈ T0 + r (tR – tT0),
(1)
where T0 is initial temperature of the analysis, °C, r is
the rate of temperature rise, °C min–1, tR retention time,
min, tT0 is duration of the initial isothermal section,
min.
To calculate the retention indices, in parallel with
each sample in the same conditions the retention times
of the reference n-alkanes C8–C20 were measured.
Calculations were performed using the QBasic
software [33]. The values of normal boiling points of
organic compounds necessary for the evaluation of the
retention indices were determined along the algorithm
[18] using the ACD software (version 1994–1996).
A. Using a gas chromatography–mass spectrometer
Shimadzu QP 2010 with a silica WCOT column, phase
HP-5 MS (polydimethylsiloxane, 5% of phenyl
groups), length 25 m, internal diameter 0.20 mm
(thickness of stationary phase film 0.33 mm) in the
mode of temperature programming from 45°C (initial
isothermal section 1 min) to 280°C (isotherm 2 min) at
a rate 5°C min–1. The linear velocity of carrier gas
(helium) 40 cm s–1, injector temperature 100°C, split
ratio 1:200.
REFERNCES
B. On the Agilent 5975 gas chromatograph with
mass spectrometric detector Agilent 7000 using a
WCOT quartz column with the polydimethylsiloxane
stationary phase HP Ultra-1, length 17 m, internal
diameter 0.20 mm (thickness of stationary phase film
0.11 mm) using temperature programming from 40°C
to 200°C (isotherm 2 min) at a rate of 2 deg min–1. The
linear velocity of carrier gas (helium) 48 cm s–1, the
evaporator temperature 100°C, split ratio 1:200.
1. Ivanova, N.T. and Frangulyan, L.A., Gazo-
khromatograficheskii analiz nestabil'nykh
i
re-
aktsionnosposobnykh soedinenii (Gas Chromatography
Analysis of Instable and Reactive Compounds),
Moscow: Khimiya, 1979.
2. Zenkevich, I.G. and Bystrova, G.I., Zh. Analit. Khim.,
1985, vol. 40, no. 9, p. 1686.
3. Zenkevich, I.G. and Yandovskii, V.N., Khim.
Geterotsikl. Soed., 1984, no. 5, p. 623.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 82 No. 10 2012

STABILITY OF DIAZOCARBONYL COMPOUNDS
1685
4. Zenkevich, I.G., Makarov, E.D., and Makarov, A.A.,
J. Chem. Inf. Model., 2007, vol. 47, p. 975.
and Klimova, I.O., Analitika i kontrol’, 2006, vol. 10.
20. Kornilova, T.A., Ukolov, A.I., Kostikov, R.R., and
Zenkevich, I.G., Abstract of Papers, 5th Int.. Symp.
“Chemistry of Aliphatic Diazocompounds,” St.
Petersburg, Russia, 2011, p. 55.
21. Kornilova, T.A., Ukolov, A.I., Kostikov, R.R., and
Zenkevich, I.G., Abstract of Papers, Int. Conf. “Mass
Spectrometry and Its Practical Problems,” Moscow:
2011, OU-7, p. 104.
no. 2, p. 175.
5. de Zeeuw, J., Strohm, V., Studsen, G., and English, C.,
Abstract of Papers, 34th Int. Symp. on Capillary
Chromatogr. Riva del Garda, Italy., 2010, p. 137.
6. Barreto, G.P., Canizo, A.I., and Eyler, G.N.,
Chromatographia, 2006, vol. 63, nos. 5–6, p. 261.
7. Axe, B.P., J. Pharm. Biomed. Anal., 2006, vol. 41, p. 804.
22. Akhlaghinia, B. and Samiei, S., J. Braz. Chem. Soc.,
8. NIST/EPA/NIH Mass Spectral Library. Software/Data
Version (NIST08); NIST Standard Reference Database,
Number 69, August 2008, National Institute of
Standards and Technology, Gaithersburg, MD 20899;
http://webbook.nist.gov.
2007, vol. 18, no. 7, p. 1311.
23. Zarchi, M.A.K. and Escandari, Z., J. Appl. Polymer Sci.,
2011, vol. 121, no. 4, p. 1916.
24. Nefedov, O.M., Ioffe, A.I., and Menchikov, L.G.,
Khimiya karbenov (Chemistry of Carbenes), Moscow:
Khimiya, 1990.
9. Paulett, G. and Ettinger, R., J. Chem. Phys., 1963,
vol. 39, no. 3, p. 825.
10. Wulfman, D.S., Roberts, J., Henderson, D.K., Romine, J.C.,
McDaniel, R.S., Carver, L., and Beistel, D.W., Canad.
J. Chem., 1984, vol. 62., P. 554.
11. Kuruc, J., Kardosova, E., Rodina, L.L., and Nikola-
ev, V.A., Abstract of Papers, 9th Czechoslovak Spec-
troscopic Conf., Ceske Budejovice, 1992, Rep. S13.
25. Schollkopf, U., Tonne, P., Schafer, H., and Narkusch, P.,
Ann. Chem., 1968, vol. 722, p. 45.
26. Rodina, L.L. and Korobitsyna, I.K., Usp. Khim., 1967,
vol. 36, no. 4, p. 611.
27. Zenkevich, I.G., Eliseenkov, E.V., Kasatochkin, A.N.,
Zhakovskaya, Z.A., and Khoroshko, L.O., J. Chro-
matogr. A, 2011, vol. 1218, p. 3291.
12. Danheiser, R.L., Miller, R.F., Brisbois, R.G., and Park, S.Z.,
J. Org. Chem., 1990, vol. 55, no. 6, p. 1959.
28. Zenkevich, I.G., Chemom. Intel. Lab. Syst., 2004,
13. Woolsey, N.F. and Khalil, M.H., J. Org. Chem., 1972,
vol. 72, p. 233.
vol. 37, no. 15, p. 2405.
29. Zenkevich, I.G. and Ioffe, B.V., Interpretatsiya mass-
spektrov organicheskikh soedinenii (Interpretation of
Mass Spectra of Organic Compounds), Leningrad:
Khimiya, 1986.
14. Lebedev, A.T., Sharbatyan, P.A., Sipyagin, A.M.,
Kartsev, V.G., and Petrosyan, V.S., Khim. Geterotsikl.
Soed., 1982, no. 8, p. 1056.
15. Lebedev, A.T., Sharbatyan, P.A., Sipyagin, A.M.,
Kartsev, V.G., and Petrosyan, V.S., Khim. Geterotsikl.
Soed., 1982, no. 10, p. 1332.
16. Lebedev, A.T., Samguina, T.Yu., Petrosyan, V.S.,
Blumenthal, T., Sipyaguin, A.M., and Kartsev, V.G.,
Org. Mass Spectrom., 1992, vol. 27, no. 6, p. 730.
30. Weigand-Hilgetag, Methods of Experiment in Organic
Chemistry, Moscow: Khimiya, 1968.
31. Organic Syntheses. Diazoacetophenone, 1973, vol. 53,
p. 35; 1988, Coll. vol. 6, p. 368.
32. Organic Syntheses. Butyryl Chloride, 1929, vol. 9, p. 32;
1947, Coll. vol. 1, p. 147.
17. Lebedev, A.T., Mass Spectrom. Rev., 1991, vol. 10,
33. Stolyarov, B.V., Savinov, I.M., Vitenberg, A.G.,
Kartsova, L.A., Zenkevich, I.G., Kalmanovskii, V.I.,
and Kalambet, Yu.A., Prakticheskaya gazovaya i
zhidkostnaya khromatografiya (Practical Gas and
Liquid Chromatography), St. Petersburg: S.-Peterburg.
Gos. Univ., 2002.
no. 2, p. 91.
18. Zenkevich, I.G., Abstract of Papers, 23rd Int. Symp. on
Capillary Chromatogr., Riva del Garda, Italy, 2000,
Rep. A.17.
19. Stein, S.E., Babushok, V.I., Brown, R.L., and Linstrom, P.J.,
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 82 No. 10 2012