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1.
An improved and general synthesis of saccharin methylthio and methylsulfone derivatives from chlorosubstituted saccharins is presented. A large‐scale procedure for preparation of chloro‐substituted saccharins was developed. Treatment of the saccharin chlorides with sodium thiomethoxide and t‐BuOK in DMF gave the saccharin methyl sulfides, which upon chromium(VI) oxide catalyzed oxidation with periodic acid afforded the corresponding saccharin methylsulfones in high yields.  相似文献   

2.
An efficient preparation of α‐amino phosphonates by the one‐pot condensation of aldehydes, amines, and dialkyl phosphites using catalytic amounts of lanthanide chloride under mild conditions is successfully developed. Moreover, the catalyst is water‐tolerant and could be recovered and reused. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:389–392, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20219  相似文献   

3.
A new synthetic route to build the [1,2,4]triazino[3,4‐ f]purine nucleus is described. The novel [1,2,4]‐triazino[3,4‐ f]purine‐4,6,8(l H,7 H,9 H)‐trione derivatives were obtained by condensation of 8‐hydrazinotheophylline with appropriate glyoxylic acids via the intermediate hydrazones.  相似文献   

4.
A new method for the preparation of 4‐substituted 3,4‐dihydro‐1H‐2,1,3‐benzothiadiazine 2,2‐dioxides is described. Treatment of t‐butyl N‐phenylsulfamoylcarbamate derivatives ( 1 ) with different aldehydes afforded the corresponding intramolecular cyclized products 2 under trifluoroacetic acid conditions. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:192–197, 2011; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20670  相似文献   

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2‐Aminobenzoic acid reacts readily, in the presence of triethylamine, with hydrazonoyl chlorides ( 5a‐c ) (precursors of the reactive nitrile imine 1,3‐dipolar species) to afford high yields of the corresponding acyclic amidrazone adducts ( 6a‐c ). The latter adducts undergo, in THF in presence of 1,1‐carbonyldiimida‐zole, smooth intramolecular cyclization involving the activated carboxyl and the NH‐ termini to deliver unequivocally the respective dihydro‐1,3,4‐benzotriazepin‐5‐ones ( 7a‐c ).  相似文献   

7.
2‐Alkylthio‐5‐phenylmethylidene‐4H‐imidazol‐4‐ones 4 were synthesized by S‐alkylation of 2‐thioxo‐3‐alkyl(aryl)‐4‐imidazolidinones 3 , which were obtained via cyclization of isothiocyanates 2 with aliphatic(aromatic) primary amines. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:348–351, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10160  相似文献   

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The synthesis of 1,1,1,3‐tetranitro‐3‐azabutane is disclosed and compared with the known method. The structure of 1,1,1,3‐tetranitro‐3‐azabutane is identified by multi‐nuclear NMR spectroscopy and X‐ray single crystal structure determination.  相似文献   

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ν‐Dysprosium borate (ν‐DyBO3) was synthesized under conditions of high temperature and pressure in a Walker‐type multi‐anvil apparatus at 3 GPa and 1323 K. The compound is isotypic with the already known ν‐samarium and ν‐europium orthoborates.  相似文献   

12.
A series of 5‐aryl‐1‐arylaminomethyl‐1,3,5‐triazinane‐2‐thiones has been prepared in a one‐step procedure from condensation of readily available aromatic amines with thiourea and formaldehyde. A mechanism is presented to account for the formation of the products. The overall sequence provides a simple and efficient route to prepare in good to excellent yields and in a short experimental time. J. Heterocyclic Chem., (2012).  相似文献   

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14.
Treatment of 2‐ethynylanilines with P(OPh)3 gives either 2,2‐diphenoxy‐2‐λ5‐phosphaquinolines or 2‐phenoxy‐2‐λ5‐phosphaquinolin‐2‐ones under transition‐metal‐free conditions. This reaction offers access to an underexplored heterocycle, which opens up the study of the fundamental nature of the N?PV double bond and its potential for delocalization within a cyclic π‐electron system. This heterocycle can serve as a carbostyril mimic, with application as a bioisostere for pharmaceuticals based on the 2‐quinolinone scaffold. It also holds promise as a new fluorophore, since initial screening reveals quantum yields upwards of 40 %, Stokes shifts of 50–150 nm, and emission wavelengths of 380–540 nm. The phosphaquinolin‐2‐ones possess one of the strongest solution‐state dimerization constants for a D–A system (130 M ?1) owing to the close proximity of a strong acceptor (P?O) and a strong donor (phosphonamidate N? H), which suggests that they might hold promise as new hydrogen‐bonding hosts for optoelectronic sensing.  相似文献   

15.
An efficient route for the synthesis of 4‐substituted‐2‐quinolinone‐3‐carboxylic acid ethyl esters has been developed through Suzuki or Sonogashira reactions. The advantages of the method include high yields, operational simplicity, and suitability for medicinal modification of 4‐substituted quinolinones and their derivatives.  相似文献   

16.
A well‐defined and monofunctional poly(3‐hexylthiophene)‐based (P3HT) macroinitiator has been obtained through a clean, simple, and an efficient multistep synthesis process. The macroinitiator is obtained via intermolecular radical 1,2‐addition onto an ω‐acrylate‐terminated P3HT macromonomer. In a second step, well‐defined rod‐coil block copolymers were obtained by nitroxide‐mediated radical polymerization (NMRP) using the so‐called Blocbuilder®. The polymerization was found to be controlled with various monomers such as styrene, isoprene, 4‐vinylpyridine, or methyl acrylate. This process constitutes a very promising way to obtain versatile and clean materials for organic electronics. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

17.
A simple and convenient procedure for the preparation of 2‐benzylthiobenzirnidazoles by the reaction of 2‐mercaptobenzimidazole and benzyl bromides in acetone/potassium carbonate condition has been reported and the compounds were screened for their potential antimicrobial activities.  相似文献   

18.
Efficient synthesis of biological important pyrrolo[2,1‐c][1,4]benzodiazepine‐5,11‐dione dimer linked through the C‐2 positions by fumarate group is described.  相似文献   

19.
A racemic cis/trans mixture of 5‐hexyl‐4‐methyl‐γ‐butyrolactone was easily synthesized from 1‐iodoheptane in four steps with inexpensive and readily available reagents. Our new synthesis method can be potentially employed for mass production of the 4‐methyl‐5‐hexyl‐γ‐butyrolactone as well as other poly‐alkyl substituted γ‐butyrolactones.  相似文献   

20.
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