Reduction of dipyrido ureas via 6-alkyloxydipyrido[1,2-c;2′,1′- e]imidazolium salts

Article abstract of DOI:10.1515/znb-2010-0711

Dipyrido uronium salts can readily be synthesized by alkylation of dipyrido ureas with Meerwein's reagent. Compared to the corresponding ureas, the uronium salts are more reactive towards basic or reducing agents like metal hydrides. Reactivity studies show that the uronium salts can react as alkylating agents towards DMSO, DBU and NaOEt along with release of the respective dipyrido ureas. In contrast, reduction of the dipyrido uronium salts with sodium borohydride or sodium trimethoxyborohydride in dry and degassed acetonitrile leads to the imidazolium salts 7a and 7b in moderate yields. Analysis of the by-products reveals an in situ carbene formation which can be reversed by using degassed but wet acetonitrile as solvent. The yield of 7b was increased significantly by these means.

Full text of DOI:10.1515/znb-2010-0711

Z. Kristallogr. NCS 2016; aop
Open Access
Zhi-Qiang Xiong, Xiu-Ying Song and Xu-Liang Nie*
Crystal structure of diaqua-bis(2-methyl-1H-
2
imidazole-4,5-dicarboxylato-κ -O,N)cadmium(II)
tetrahydrate, C H CdN O
12 22
4 14
Table 1: Data collection and handling.
Crystal:
Colourless, blocks
Size 0.22 × 0.20 × 0.16 mm
Wavelength:
µ:
Mo Kα radiation (0.71073 Å)
−
1
11.5 cm
Diꢀractometer, scan mode:
Bruker APEXII, φ and ω
59.0°, >99%
2
θmax, completeness:
N(hkl)measured, N(hkl)unique, Rint: 3874, 1879, 0.023
Criterion for Iobs, N(hkl)gt:
N(param)reꢁned:
Programs:
Iobs > 2 σ(Iobs), 1863
164
SHELX [10], Bruker programs [11]
DOI 10.1515/ncrs-2016-0068
Received March 4, 2016; accepted June 13, 2016; available
online June 25, 2016
Table 2: Fractional atomic coordinates and isotropic or equivalent
2
isotropic displacement parameters (Å ).
Atom
x
y
z
Uiso*/Ueq
Abstract
Cd1
O1
1.0000
0.9506(3)
0.8494(3)
0.6709(3)
0.7244(3)
0.7573
0.6869(3)
0.8578(3)
0.7542(3)
0.8039(4)
0.6999
1.0000
1.2382(2)
1.3403(2)
0.9966(3)
1.2393(3)
1.2755
1.1638(4)
0.9324(2)
0.8366(3)
0.6378(3)
0.6723
0.0000
0.05901(19)
0.2426(2)
0.69875(19)
0.5169(2)
0.4248
−0.1149(3)
0.2449(2)
0.4890(2)
0.3565(3)
0.2909
0.03118(11)
0.0387(4)
0.0408(4)
0.0393(4)
0.0416(4)
0.062*
0.0604(6)
0.0269(4)
0.0284(4)
0.0393(5)
0.059*
¯
C12H22CdN4O14, triclinic, P1 (no. 2), a = 7.188(2) Å, b =
8
.895(3) Å, c = 9.771(3) Å, α = 63.148(3)°, β = 76.750(3)°, O2
3
γ = 66.225(3)°, V = 509.2(3) Å , Z = 1, Rgt(F) = 0.0253, O4
2
O3
H3
O5
N1
N2
wRref(F ) = 0.0676, T = 296(2) K.
CCDC no.: 1484775
The crystal structure is shown in the ꢀgure. Tables 1 and
2
contain details of the measurement method and a list of C1
H1A
H1B
H1C
C2
the atoms including atomic coordinates and displacement
parameters.
0.7753
0.9337
0.5575
0.5787
0.4581
0.3167
0.059*
0.059*
0.8083(3)
0.8322(3)
0.8804(4)
0.7670(3)
0.7169(3)
0.3235(3)
0.3486(5)
0.716(6)
0.251(5)
0.263(5)
0.692(6)
0.577(4)
0.334(7)
0.334(7)
0.7998(3)
1.0586(3)
1.2241(3)
1.0005(3)
1.0797(3)
0.3294(3)
0.4207(4)
0.768(5)
0.270(4)
0.424(3)
1.064(3)
1.218(4)
0.521(3)
0.411(5)
0.3627(3)
0.2981(2)
0.1921(3)
0.4507(2)
0.5653(3)
1.0042(2)
0.2413(3)
0.578(2)
0.0283(4)
0.0259(4)
0.0304(5)
0.0268(4)
0.0298(5)
0.0526(5)
0.0689(7)
0.083*
Source of material
The title compound was synthesized by a hydrothermal
C3
C5
method under autogenous pressure. A mixture of CdCl2·H2O C4
C6
O6
O7
H2
*Corresponding author: Xu-Liang Nie, Key Laboratory of Natural
Product Research and Development/College of Sciences, Jiangxi
Agricultural University, Nanchang 330045, People’s Republic of
China, e-mail: niexuliang1981@163.com
H3W
H4W
H1W
H2W
H5W
H6W
1.056(4)
0.936(4)
0.083*
0.083*
Zhi-Qiang Xiong: Center of Analysis and Testing, Nanchang
Hangkong University, Nanchang 330063, People’s Republic of
China
Xiu-Ying Song: College of Sciences, Jiangxi Agricultural University,
Nanchang 330045, People’s Republic of China
−0.100(5)
−0.081(5)
0.229(4)
0.083*
0.083*
0.083*
0.166(3)
0.083*
©
2016 Zhi-Qiang Xiong et al., published by De Gruyter.
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.
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2
Ë
Xiong et al.: C12H22CdN4O14
(0.029 g, 0.1 mmol), 2-methyl-1H-imidazole-4,5-dicarboxylic molecular O—H· · · O hydrogen bonds link the molecules into
acid (H3MIDA) (0.034 g, 0.2 mmol) and distilled water (15 mL) a three-dimensional hydrogen bonds network.
was sealed in a teꢁon-lined stainless reactor (25 mL) and
heated at 120°C for 72 h, and then cooled to room temper- Acknowledgements: This work was supported by the
ature. The red block crystals were ꢀltered and washed with Research Foundation of Educational Department of Jiangxi
water and ethanol. Yield: 75% (based on H3MIDA). Analysis Province[GJJ13261]. X-ray data were collected at Instrumental
calculated for C12H22CdN4O14: C, 25.80; H, 3.97; N, 10.03%; Analysis Center Nanchang Hangkong University, Nanchang,
found: C, 24.99; H, 4.19; N, 9.71%.
330063, People’s Republic of China.
Experimental details
References
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