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101.
Umesh C. Pant A. Dandia Hem Chandra Shweta Goyal Seema Pant 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):559-571
Abstract Two flavindogenides, 3-(2-chlorobenzylidene)-flavanone and 3-(2,4-dichloro- benzylidene)-flavanone reacted with six 5-substituted-2-aminobenzenethiols, the substituents being fluoro, chloro, bromo, methyl, methoxyl, and ethoxyl, to give respective 12 new compounds, 10-substituted-7-(2-chlorophenyl/2,4-dichlorophenyl)- 6H-6a,7-dihydro-6-phenyl[1]benzopyrano[3,4?c][1,5]benzothiazepines (5a–l) in 60–70% yields. The products were characterized on the basis of microanalytical data for elements and IR, 1 H, and 13 C NMR and mass spectral studies. All the synthesized compounds were evaluated for their antimicrobial activity against the bacteria,Escherichia coli and GFC,and the fungi,Aspergillus niger, Aspergillus flavus,and Curvularia lunata. 相似文献
102.
Ian W. J. Still Wang Daoquan 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):83-89
Abstract The reactions of a series of O-silylated α-ketols with trimethylsilyl cyanide have been investigated. Formation of the expected 0-trimethylsilyl cyanohydrins as major products has been shown to be accompanied by the hitherto unsuspected formation of a disiloxane by a proposed intramolecular SN2 displacement mechanism. The latter reaction is, surprisingly, independent of the substitution pattern in the silylated ketol. Formation of the side-product, however, increases in all cases with increasing dilution. The α,β-epoxynitrile 9, a second side-product expected, along with the observed disiloxane, by our proposed mechanism was synthesized by an unambiguous route. A control experiment showed the epoxynitrile to be completely destroyed under the usual conditions of reaction with trimethylsilyl cyanide. 13C NMR data have been obtained for most of the compounds in this study. 相似文献
103.
Toru Minami Ryoji Kouno Tatsuo Okauchi Mitsuharu Nakamura Junji Ichikawa 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):689-692
The α-phosphonovinyl anions, generated in situ from treatment of β-hetero-substituted vinyl-phosphonates 1a-c with LDA (or LTMP), were trapped with various electrophiles such as chlorotriorganosilanes, chlorotrimethylgermane, chlorotriorganotins, dimethyl disulfide, and halogen to afford the corresponding β-hetero-substituted α-functionalized vinylphosphonates 2–14 in good to excellent yields. The Friedel-Crafts reaction of α-(silyl) or α-(germyl)phosphonoketene dithioacetals 2, 9 or 4 with acid chlorides gave α-acylated phosphonoketene dithioacetals 15–19 in 53–91 % yields. The palladium-catalyzed cross-coupling reaction of β-ethoxy-α-(tributylstannyl)vinylphosphonate 13 with a variety of organic halides (R = acyl, allyl, aryl etc.) provided β-ethoxy-α-substituted vinylphosphonates 20–25 in good to moderate yields. The palladium-mediated cross-coupling reaction of α-(iodo)-vinyl-phosphonates 7, 14 with terminal acetylenes afforded α-alkynylated vinylphosphonates 26–29 in 69–83 % yields. 相似文献
104.
Samuel O. Grim Anthony W. Yankowsky 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):191-195
Abstract The 31P chemical shifts of eleven (4-ZC6H4)3P compounds show a slight correlation with the Hammet [sgrave]para constant of Z. The unusually large upfield chemical shifts of (2-ZC6H4)3P compounds are attributed to an extreme “gamma” effect caused by the restricted conformations due to the steric influence of the ortho substituents. Chemical shifts are given for about thirty triarylphosphines, and group contributions to phosphine chemical shifts are listed for twenty-one aryl groups. 相似文献
105.
Jeffrey Trautmann Alirica I. Suarez Pakamas Tongcharoensirikul Gregory W. Muth Charles M. Thompson 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):471-477
Dimethyl thiophosphite reacts with aliphatic aldehydes and ketones, Michael acceptors, and N-benzyl imines to afford excellent yields of f -hydroxy phosphonothionates, g -substituted phosphonothionates and f -amino phosphonothionates, respectively. Dealkylation of f -amino phosphonothionates affords N-benzyl f -amino phosphonothioic acids. Dimethyl thiophosphite reacts with electrophiles at a significantly greater rate than dimethyl phosphite. 相似文献
106.
M. El-borai M. F. Abdel-megeed 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):165-173
Abstract The mass spectral fragmentation of thiophenotropone, thiophenotropilidene derivatives and their iron and chromium tricarbonyl complexes are fully reported and discussed. The fragmentation patterns of the complexes are characterised by successive loss of three carbonyl groups. In general, the resulting ions after elimination of the metal behave in the same manner as the organic ligand. The iron complexes behave differently from their corresponding chromium complexes. The thiopheno[b]tropilidene iron tricarbonyl complex and its isomer thiopheno[c]tropilidene iron tricarbonyl complex could not be differentiated by mass spectrometry, such differentiation was achieved by proton magnetic resonance. 相似文献
107.
A. A. F. Wasfy M. S. Amine M. M. H. Arief S. G. Donia A. A. Aly 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):1359-1368
4-(5,5-Dioxodibenzothiophen-2-yl)-4-oxo-2-butenoic acid ( 1 ) was condensed with compounds containing active methylene groups under Michael reaction conditions to form the Michael adducts 2a-c , 3a-c , and 4a-b . The behavior of Michael adduct towards the action of hydrazine hydrate was investigated. The compounds were tested for biological properties. 相似文献
108.
Bin Wang Zhi-Wei Miao Ru-Yu Chen 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2739-2748
A series of naphthoquinone-fused phosphorus heterocycles was synthesized via a three-component Mannich-type reaction. 2-Chloroethoxylphosphorodichloridite was used as a phosphorus substrate to explore the structure–activity relationships of the 2-position of the heterocycles. One spiral heterocycle compound was structurally characterized by a single-crystal X-ray diffraction analysis. 相似文献
109.
110.