نتایج جستجو برای: 4 dioxane
تعداد نتایج: 1304616 فیلتر نتایج به سال:
In the title mol-ecule, C(16)H(15)FO(4), the fused 1,3-dioxane and cyclo-hexane rings exhibit a bath and a chair conformation, respectively. In the crystal, weak inter-molecular C-H⋯O hydrogen bonds link the mol-ecules into centrosymmetric dimers.
A nickel- and manganese-catalyzed decarboxylative cross coupling of α, β-unsaturated carboxylic acids with cyclic ethers such as tetrahydrofuran and 1, 4-dioxane was developed. Oxyalkylation was achieved when nickel acetate was used as catalyst, while manganese acetate promoted the reaction of alkenylation.
In the title mol-ecule, C(17)H(18)O(5), which was prepared by the reaction of (R)-1,5-dioxaspiro-[5.5]undecane-2,4-dione and 4-meth-oxy-benzaldehyde with ethanol, the 1,3-dioxane ring is in a distorted envelope conformation with the spiro C atom forming the flap. The crystal structure is stabilized by weak inter-molecular C-H⋯O hydrogen bonds.
Solvatochromic shifts of the electronic states of a chromophore can be used as a measure of solute-solvent interactions. The shifts of the electronic states of a model organic chromophore, p-nitroaniline (pNA), embedded in solvents with different polarities (water, 1,4-dioxane, and cyclohexane) are studied using a hybrid quantum mechanics/molecular-mechanics-type technique in which the chromoph...
The asymmetric unit of the title compound, C11H11N5O2S·0.5C4H8O2, contains one 3-(p-tol-yl)sydnone 4-thio-semi-carba-zone mol-ecule and a half mol-ecule of 1,4-dioxane, which lies abount an inversion centre. The sydnone ring is almost planar, with a maximum deviation of 0.002 (1) Å, and forms a dihedral angle of 46.31 (5)° with the benzene ring. In the crystal, the two components are linked int...
In the crystal structure of the title compound, C(17)H(16)N(2)O(3)·0.5C(4)H(8)O(2), pairs of N-H⋯N hydrogen bonds link mol-ecules into dimers with R(2) (2)(12) motifs, which are connected by N-H⋯O hydrogen bonds, forming a supra-molecular array in the ab plane. The 1,4-dioxane ring, which lies about an inversion center, adopts a chair conformation.
The Reduction of Pyridine to 1,4-Dihydropyridine by Lithiumtetrahydroborate in the Presence of Water
In the presence of water lithium tetrahydroborate is capable of reducing pyridine to 1,4dihydropyridine. The product, lithiumtetrakis(pyridine) tetrakis(1,4-hydropyridyl)borate, was isolated and characterized by NMR and IR spectroscopy and single crystal X-ray diffraction. [Li(py)4][B(pyH)4]2(1,4-dioxane) crystallized in space group P42/n, Z = 2. Similarly, NaBH4 can also reduce pyridine in the...
The alkylating potential of beta-propiolactone (BPL), beta-butyrolactone (BBL), gamma-butyrolactone, and delta-valerolactone, which can be formed by the in vivo nitrosation of primary amino acids, was investigated kinetically. The nucleophile NBP, 4-(p-nitrobenzyl)pyridine, a trap for alkylating agents, was used as an alkylation substrate. The alkylation reactions were performed under mimicked ...
1,4-Dioxane (CAS No. 123-91-1) is used primarily as a solvent or as a solvent stabilizer. It can cause lung, liver, and kidney damage at sufficiently high exposure levels. Two physiologically based pharmacokinetic (PBPK) models of 1,4-dioxane and its major metabolite, hydroxyethoxyacetic acid (HEAA), were published in 1990. These models have uncertainties and deficiencies that could be addresse...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید