Mendeleev
Communications
Mendeleev Commun., 2015, 25, 395–396
Synthesis and molecular properties of formic hydrazides
Liya O. Belova,*a Maria V. Pletneva,a Nataliya A. Golub,a Aleksei D. Kirilin,a
Viktor D. Sheludyakov,b Pavel A. Storozhenkob and Alexander A. Korlyukovc
a M. V. Lomonosov Moscow State University of Fine Chemical Technology, 119571 Moscow, Russian
Federation. E-mail: belova.lya@inbox.ru
b State Researh Institute for Chemistry and Technology of Organoelement Compounds, 105118 Moscow,
Russian Federation
c A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, 119991 Moscow,
Russian Federation
DOI: 10.1016/j.mencom.2015.09.029
The existence of 1,3-silatropic transformation in N',N'-dimethyl-N-(trimethylsilyl)formic hydrazide was discovered. In the crystal, its
molecules form chains due to bifurcated hydrogen bonds.
Formamides are an important class of nitrogen-containing organic
compounds used as anticancer chematherapeutic agents,1 pre-
cursors of fungicides and herbicides2 and starting materials in
the preparation of linear and heterocyclic compounds.3–5 They
are obtained mostly by N-formylation of amines1–4 or their
organosilicon derivatives.5–7
In the case of highly nucleophilic amines, formylation with
alkyl formates proceeds cleanly under heating and completes after
alcohol release stops.8–10 In this manner N-(4-methoxyphenyl)-
formamide was herein obtained.† The process temperature can be
reduced to ambient one with significant raising products yields
on using ‘HEV13’ zeolite as a catalyst.
Scheme 2
1
In the H NMR spectrum of compound 2, formyl protons
resonate as two singlets, and dimethylamino protons also resonate
as two singlets. This indicates the hindrance in rotation of
--
–
N
C(O) bond in the molecule 1.
On moving to less nucleophilic hydrazines or their hydrates,
the process nature is changed and formylhydrazides can be
obtained in quantitative yields only at low temperature (~0°C,
Scheme 1).‡
O(1)
C(2)
N(1)
C(1)
Me2NNH2
Me2NNHC(O)H
EtOC(O)H
– EtOH
1
N(2)
H(2)
H2NNH2·H2O
HC(O)NHNHC(O)H
C(2A)
2
Scheme 1
Figure 1 Molecular structure of N',N'-dimethylformic hydrazide 1. Selected
bond lengths (Å) and angles (°): O(1)–C(1) 1.231(3), N(1)–N(2) 1.420(3),
N(1)–C(2) 1.4691(17), C(1)–N(2) 1.329(3), N(2)–H(2) 0.92; N(2)–N(1)–C(2)
109.33(13), C(2)–N(1)–C(2A) 111.84(18), O(1)–C(1)–N(2) 126.6(2), C(1)–
N(2)–N(1) 120.0(2), C(2)–N(1)–N(2)–C(1) 118.63(13). The C(2A) atom
was obtained from the base one by means of symmetrical transformation of
–x + 1, y, z.
Such an effect can be explained by the increase in hydrogen
acidity at nitrogen in hydrazines due to the influence of a neigh-
boring electronegative substituent resulting in easier deprotona-
tion in comparison with high-basic amines (Scheme 2).
†
IR spectra were recorded on a Specord 75 IR instrument in Nujol.
1H NMR spectra were recorded on Bruker WP-300 (300 MHz) and
Bruker DRX500 (500 MHz) spectrometers in C6D6 or CDCl3.
N,N'-Diformylhydrazine 2. A mixture of hydrazine monohydrate (10.5 g,
0.21 mol) and ethyl formate (31.2 g, 0.42 mol) was kept at 0°C for 48 h.
The crystals formed were filtered to afford 36.54 g (99%) of compound
2, mp 155–156°C. IR (KBr, n/cm–1): 3300 (N–H), 3140 (C–H), 1620
(C=O). 1H NMR (300 MHz, CDCl3) d: 7.91 and 8.14 (d, 1H, CH), 9.95
(br.s, 2H, NH). Found (%): C, 27.32; H, 4.60; N, 31.87. Calc. for
C2H4N2O2 (%): C, 27.28; H, 4.58; N, 31.81.
N',N'-Dimethyl-N-(trimethylsilyl)formic hydrazide 3. A mixture of com-
pound 1 (10.04 g, 0.114 mol), chlorotrimethylsilane (12.38 g, 0.114 mol),
triethylamine (16.19 g, 0.160 mol) and 100 ml of diethyl ether was stirred
at 35°C for 10 h. Then, triethylamine hydrochloride was filtered off. The
filtrate was distilled to give 15.71 g (86%) of product 3, bp 143–144°C,
nD20 1.4305. IR (KBr, n/cm–1): 3160 (C–H), 1650 (C=O). 1H NMR
(300 MHz, CDCl3) d: 0.3 (s, 9H, SiMe), 2.4 (s, 6H, NMe), 7.62 [s, 1H,
C(O)H]. Found (%): C, 44.95; H, 10.03; N, 17.42; Si, 17.56. Calc. for
C6H16N2OSi (%): C, 44.96; H, 10.01; N, 17.48; Si, 17.52.
N-(4-Methoxyphenyl)formamide. A mixture of 4-methoxyaniline (10 g,
0.0812 mol) and ethyl formate (6.02 g, 0.0812 mol) was heated at 100°C
for 1 h until evolution of ethanol ceased. The crystals formed were filtered
giving 11.04 g (90%) of the product, mp 76–78°C. IR (KBr, n/cm–1):
1
3240 (N–H), 3190 (C–H), 1670 (C=O). H NMR (300 MHz, C6D6) d:
3.25 (s, 3H, OMe), 6.22 (br.s, 1H, NH), 6.71 (d, 2H, CH), 7.43 (d, 2H,
CH), 7.82 (1H, CH). Found (%): C, 63.55; H, 5.95; N 9.25. Calc. for
C7H9NO2 (%): C, 63.5; H, 5.95; N, 9.26.
‡
N',N'-Dimethylformic hydrazide 1. A mixture of N',N'-dimethyl-
hydrazine (21.53 g, 0.36 mol) and ethyl formate (26.54 g, 0.36 mol) was
kept at ~0°C for 12 h. The crystals formed were filtered to give 31.06 g
(99%) of compound 1, mp 59–60°C. IR (KBr, n/cm–1): 3320 (N–H), 3160
(C–H), 1640 (C=O). 1H NMR (300 MHz, CDCl3) d: 2.45 and 2.48 (s, 3H,
CMe), 6.51 (br.s, 1H, NCH), 8.17 and 8.19 (s, 1H, CH). Found (%): C, 40.95;
H, 9.19; N, 31.83. Calc. for C3H8N2O (%): C, 40.90; H, 9.15; N, 31.79.
© 2015 Mendeleev Communications. Published by ELSEVIER B.V.
on behalf of the N. D. Zelinsky Institute of Organic Chemistry of the
Russian Academy of Sciences.
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