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本文报道了一种通过微波辅助合成5-亚甲基-2,3-二苯基-4-噻唑酮类衍生物的新型方法。在以K2CO3 为碱、H2O 为溶剂、四丁基溴化铵(TBAB)为催化剂的条件下,2,3-二苯基-4-噻唑酮与取代醛在微波辅助下发生Knoevenagel 反应,生成5-亚甲基-2,3-二苯基-4-噻唑酮类衍生物,产率最高可达85%。 相似文献
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恶唑酮及其衍生物是合成氨基酸、芳基乙酸及许多天然产物的重要中间体[1] 。一般由马尿酸与芳醛在脱水剂醋酐及催化剂如醋酸钠 [2 ]、碳酸钾[3] 、氯化锌[4 ] 、N-氯乙酰 -苯酰胺 -醋酸钠[5] 、KF-Al2 O3[6 ] 等存在下环化脱水 -缩合而得。但大都反应时间长 ,后处理复杂。1 986年 ,Gedye等人 [7]和 Gignere等人 [8]利用微波辐射有效地加速了有机化学反应 ,从此 ,作为一种新的有机合成方法引起了有机化学工作者的高度重视。本文报道将微波技术用于标题化合物的合成 ,获得了预期的效果。1 实验部分WC-1型熔点测定仪 ,温度计未校正 ;Nicol… 相似文献
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标题化合物C24H29NO4?1/2C2H5OH稨2O)由香兰素、5,5-二甲基-1,3-环己二酮、醋酸铵在微波辐射下干反应并经95%乙醇重结晶而得C24H29NO4穀2(C2H5OH稨2O)晶体。结构通过单晶X-射线衍射法确定,其晶体属单斜晶系,空间群P21/n, a = 9.810(2), b = 14.516(3), c = 17.008(3) ? b = 101.03(2), V = 2377.2(8) ?, Z = 4, Mr = 427.52, Dc = 1.195 g/cm3 , m(MoKa) = 0.082 mm-1, F(000) = 920。晶体结构用直接法解出,经全矩阵最小二乘法对原子参数进行修正,最终的偏离因子为R = 0.0406, wR = 0.0892。X-射线衍射分析结果表明,吡啶环和与之稠合的2个六员环均为信封式构象。 相似文献
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1-苯基-3-甲基-4-(4-羟基-3-甲氧基)-苯甲叉-吡唑啉酮的微波合成和晶体结构 总被引:3,自引:0,他引:3
标题化合物C18H16N2O3是由香草醛和1-苯基-3-甲基-吡唑啉酮用微波辐射反应得到,结构通过单晶X-射线衍射法确定,其晶体属单斜晶系,空间群P21/c,Mr = 308.33, a = 21.101(4), b = 7.984, c = 20.076 ? = 115.81(1)? V = 3044.8(8) ? Z = 8, Dc = 1.345 g/cm3, = 0.093 cm-1, F(000) = 1296, 最终的偏离因子为R = 0.0403, wR = 0.0780, 分子之间存在氢键,形成了网状结构。 相似文献
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标题化合物C18H21NO5是由2-呋喃亚甲叉氰乙酸酯和5,5-二甲基-1,3-环己酮在醋酸铵存在下用微波辐射反应得到,结构通过单晶X-射线衍射法确定,其晶体属三斜晶系,空间群P 睿琈r =332.36,a =11.232(2),b =13.048(2),c =13.274(3),α=105.7(1),β=95.68(2),g =109.56(1)? V=1752.4(6)3,Z=2,Dc=1.276Mg·m-1, =0.093mm-1,F(000)=704, 最终的偏离因子为R=0.0431,wR=0.0973,在分子结构中平面 1 (呋喃环) 与平面2 ((C(5)、 C(6)、C(9)、O(1))之间的二面角为 84.70°, 平面2 与平面 3 (C(1)、C(4)、C(5)、C(6)) 之间的二面角为 2.9°, 平面 1 与平面3 之间的二面角为 85.9°。吡喃环和与吡喃环合的六员环为信封式结构。 相似文献
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Peter Rogl 《Monatshefte für Chemie / Chemical Monthly》1980,111(2):517-527
The crystal structure of LaIr4B4 has been refined from single crystal counter data. LaIr4B4 is tetragonal,P42/n,Z=2, isotypic with NdCo4B4, |F|/|F
o|=0.039 for 312 independent reflections [|F
o|>2 (F
o)]. ThIr4B4 and ThOs4B4 also belong to the NdCo4B4-type structure. URu4B4 and UOs4B4 were found to crystallize with LuRu4B4-type structure. The crystal chemistry of (RE)T
4B4-phases is discussed and simple geometric relations are shown to exist between them.Dedicated to Prof.B. T. Matthias in celebration of his 60th birthday. 相似文献
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Vibrational Spectra of As4S4 and As4Se4 The vibrational spectra of solid α- and β-As4S4 and the Raman spectrum of molten As4S4 have been recorded. The assignments of the frequencies are proposed mainly based on polarization data. The Raman melt spectra suggest that As4S4 molecules (symmetry D2d) are retained in the molten state. A partial decomposition of the melt by prolonged laser irradiation was observed. The Raman spectrum of solid As4Se4 is presented and the frequencies are tentatively assigned to an As4Se4 molecule of the cradle type, possessing D2d symmetry. 相似文献
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Ab initio calculations have been performed on B4H4, B4Cl4 and B4F4 in order to aid our understanding of the bonding in these compounds, which is presumably based on a tetrahedral boron cage. This cage has only 8 electrons and so is less than that expected on the basis of the usual framework electron counting rules. Basis sets with polarisation functions were used at the SCF, CI and CPF levels of theory to confirm that the T
d
structures are indeed more stable than the D
4h
ones. Davidson-Roby population analyses were able to show that many factors, including 3-centre 2-electron bonding and backbonding from the ligand to the boron cage, are of importance in determining the relative stability of the three compounds, of which B4Cl4 is the only one that has yet been observed experimentally. 相似文献
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Die erstmals dargestellten isotypen Verbindungen Ba4SiAs4, Ba4GeAs4, Sr4SiAs4 und Sr4GeAs4 kristallisieren kubisch, Raumgruppe P4 3n, mit 8 Formeleinheiten in der Elementarzelle: In den Strukturen liegen isolierte, d.h. nur von Ba-Ionen umgebene SiAs - bzw. GeAs -Tetraeder vor. Die Verbindungen sind die bisher eindrucksvollsten Beispiele für Zintlphasen mit komplexen Anionen. Zintl Phases with Isolated SiAs4 or GeAs4 Anions: Preparation and Structure of Ba4SiAs4, Ba4GeAs4, Sr4SiAs4, and Sr4GeAs4 The new compounds Ba4SiAs4, Ba4GeAs4, Sr4SiAs4, and Sr4GeAs4 have been prepared and their structures determined. They crystallize in the cubic system, P4 3n, with axes: data see “Inhaltsübersicht”. There are isolated SiAs or GeAs tetrahedra in the structures. The compounds can be interpreted as Zintl phases with complex anions. 相似文献
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On K4PbO4 and Rb4PbO4 For the first time single crystals of K4[PbO4] have been prepared by heating K4PbO3 in O2. The structure has been refined [K4[PbO4]: 3029 I0(hkl), four circle diffractometer PW 1100, ω-scan, MoKα, R = 6.73%, Rw = 6.64%, P1 ; a = 658.62(15), b = 658.41(12), c = 986.64(21) pm, α = 79.74(2)°, β = 108.45(2)°, γ = 112.49(2)°, dx = 3.79 g · cm?3, dpyk = 3.78 g · cm?3, Z = 2; Rb4[PbO4]: a = 686.94(18), b = 684.43(18), c = 1020.73(21) pm, α = 79.28(2)°, β = 108.40(2)°, γ = 113.02(2)°, dx = 4.87 g · cm?3, dpyk = 4.85 g · cm?3, Z = 2, (from Rb2PbO3 and Rb2O)]. Both compounds are isotypic with K4SnO4. The Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated. 相似文献
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Energy differences, ΔXS‐t (X = E, H and G) (ΔXS‐t = X(singlet)‐X(triplet)) between singlet (s) and triplet (t) states are calculated at B3LYP/6‐311++G (3df,2p). The DFT calculations show that the triplet state of C4H4C is a ground state with planar conformer respect to its corresponding nonplanar singlet state. Both singlet and triplet states of C4H4M (M = Si, Ge, Sn and Pb) have a planar conformer with the singlet ground state. Four isodesmic reactions are presented for determining the stability energies, SE. NICS calculations are carried out for C4H4M to determine the aromatic character. 相似文献
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