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991.
Aromatic nitro compounds were reduced to respective amines in high yields by using 5% platinum on carbon with ammonium formate or formic acid as hydrogen donor. It was observed that the former was more efficient donor than the later. Further we have found that reduction of nitro groups occurs without hydrogenolysis of halogens and the reducible substituents which remains unchanged under the reaction conditions. 相似文献
992.
A simple and efficient procedure for the synthesis of symmetrical bis-Schiff bases has been described that employs a condensation reaction of symmetrical primary bis-amine of 5,5′-methylenebis(2-aminothiazole) with a series of aromatic aldehyde derivatives under solvent-free conditions at elevated temperature. The advantages of these reactions are simplicity of the reaction procedure, short reaction times, simple workup, catalyst-free conditions, and pure products in good to excellent yields. Details of the reaction conditions are discussed. 相似文献
993.
Functionalised α, β-unsaturated aldehydes were exclusively reduced to allylic alcohols with sodium-triacetoxyborohydride. Neither saturated alcohol nor saturated aldehydes are obtained. Conjugated ketones are not reduced. 相似文献
994.
Şaban Uysal 《合成通讯》2013,43(1):84-92
2,4,6-Tris(4-hydroxybenzimino)-1,3,5-triazine (II) has been synthesized by the reaction of 1 equiv. melamine (I) and 3 equiv. 4-hydroxybenzaldehyde and characterized by means of elemental analysis, 1H NMR, Fourier transform–infrared spectroscopy, and liquid chromatography–mass spectrometry (LC-MS). 2,4,6-tris(4-(2-phenyl-2-keto-hydroxyiminoyloxy)benzimino)-1,3,5-triazine L (III) has been synthesized by the reaction of 1 equiv. II and 3 equiv. chloroisonitrozoacetophenone and characterized by means of the same methods. Four novel trinuclear Fe(III) and Cr(III) complexes involving tetradentate Schiff bases N,N′-bis(salicylidene)ethylenediamine-(salenH2) or bis(salicylidene)-o-phenylenediamine-(salophen H2) with L (III) have been synthesized and characterized by means of elemental analysis, Fourier transform–infrared spectroscopy, LC-MS (ESI+), and thermal analyses. The metal ratios of the prepared complexes have been determined using atomic absorption spectroscopy. The aim of the present study is to synthesize novel tridirectional-trinuclear systems and to present their effects on magnetic behavior of [salen or salophenFe(III)/Cr(III)] capped complexes. The complexes have also been characterized as low-spin distorted octahedral Fe(III) and as distorted octahedral Cr(III) bridged by keton-oxime group. 相似文献
995.
Gunnar Aksnes 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):227-238
Abstract The 1,2,3-trithiolan of endo-dicyclopentadiene, C10H12S3 (1) can be polymerized to give low molecular weight polymers (C10H12S3)n, n = 3–6, by heating or by exposure to UV irradiation. The polymers differ according to the method of polymerization as revealed by their n.m.r. spectra. Depolymerization of both types of polymer can be achieved by heating with amines, and especially with R3N. Desulphurization of (1) by Na2SO3 or triphenylphosphine produces a polymer of composition (C10H12S2)n, n= ca 18–19. The depolymerization of this material by Et3N regenerated some (1). 相似文献
996.
Kiran Singh Dharampal Vipin Parkash 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2784-2794
The Schiff bases derived from condensation of s-triazole with heterocyclic aldehydes and their 1:1 and 1:2 complexes have been synthesized. These complexes have been characterized by elemental analyses, molar conductance and spectroscopic studies, including UV, IR, 1H, 13C, 29Si, and 119Sn NMR spectroscopy. On the basis of these studies, the resulting complexes have been proposed to have trigonal bipyramidal and octahedral geometries. The biological activity of these complexes against various fungi has been investigated. 相似文献
997.
Fatma El-Mariah 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2795-2806
Thieno[2,3-c]pyridazine 2 was selected as the starting material for the synthesis of some novel 5-arylidene amino and 5-thiazolidine derivatives. The structures of the synthesized compounds were elucidated by elemental analyses and spectral data. The antimicrobial and antifungal activities of the newly synthesized products were measured against some microorganisms. 相似文献
998.
Shobhana Sharma Asha Jain Sanjiv Saxena 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1676-1688
Titanium(IV) complexes of the general formula TiL(OPr i )2 [where LH2 = R CH3 where R = ─C6H5, ─C6H4Cl(p)] were prepared by the interaction of titanium isopropoxide with sterically hindered Schiff bases derived from heterocyclic β -diketones in 1:1 molar ratio in dry benzene. The complexes TiL(OPr i )2 were used as versatile precursors for the synthesis of other titanium(IV) complexes. Titanium(IV) complexes of the type TiLL'(OPr i ) (where L'H═R1R2C═NOH, R1 = R2 = ─CH3; R1 = ─CH3,R2 = ─C6H5; R1 = ─COC6H5, R2 = ─C6H5) were synthesized by the reaction of TiL(OPr i )2 with ketooximes (L'H) in equimolar ratio in dry benzene. Another type of titanium(IV) complexes having the general formula TiLGH(OPr i ) (where GH2═HO─G─OH, G = ─CH2─CH2─) have been prepared by the reaction of TiL(OPr i )2 with glycol in 1:1 molar ratio in dry benzene. Plausible structures of these new titanium(IV) complexes have been proposed on the basis of analytical data, molecular weight measurements, and spectral studies. 相似文献
999.
Shobhana Sharma Asha Jain Sanjiv Saxena 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1689-1701
Zirconium(IV) Schiff base chelates having the general formula ZrL(OPr i )2 [where LH 2 = R CH 3 , R = –C 6 H 5 , –C 6 H 4 Cl(p)] were synthesized by the reaction of Zr(OPr i )4.Pr i OH with sterically constrained sulfur-containing Schiff bases of heterocyclic β -diketones in a 1:1 molar ratio in dry refluxing benzene. The complexes ZrL(OPr i ) 2 were used as important precursors for the synthesis of the complexes of the type Zr(L) 2 . The complexes, Zr(L) 2 , were prepared by the interaction of precursor ZrL(OPr i ) 2 with sterically constrained sulfur-containing Schiff bases of heterocyclic β -diketones in a 1:1 molar ratio in dry benzene. The structures of these zirconium(IV) chelates have been discerned with the help of elemental analyses, physicochemical studies, and spectral [IR and NMR ( 1 H and 13 C)] data. A distorted trigonal bipyramidal and a distorted octahedral geometry may be assigned to zirconium(IV) chelates of the types ZrL(OPr i ) 2 and Zr(L) 2 , respectively. 相似文献
1000.
Nurşen Sari 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10):1609-1618
A novel polymeric‐Schiff base derived from the condensation reaction poly(acryl amid) and indole‐3‐carboxaldehyde has been synthesized and their Co(II) and Ni(II) complexes have been prepared. Mol ratio of acrylamid group and Schiff bases group was estimated by means of height of ‐CH multiple peaks and –CH=N‐ peak in 1H‐NMR spectrum. The studied substances were characterized by molar conductance, magnetic susceptibility, electronic and IR spectral studies. In addition, main units have been suggested with elemental analysis for these substances, and than the weight average molecular weight (Mw) has been suggested. The number average molecular weight (Mn) was determined with a vapor pressure osmometer. Polydispersity index (PDI) found to be ca 1.7 from Mw/Mn for poly‐Schiff bases and their Co(II) and Ni(II) complexes. PAA‐Schiff bases were found to have the highest thermal stablility compared to that of the Co(II) and Ni(II) complexes. The conductivities of the PAA‐Schiff bases and their complexes were measured by the four‐probe technique and were found in the range 10?5?10?6 S cm?1. 相似文献