Novel Convenient Synthesis of Rivastigmine

A novel and convenient synthesis of rivastigmine has been reported. This procedure provides high yield and excellent enantiomeric excess (100% ee) starting from the diastereromerically pure (S)-1-(3-methoxyphenyl)-N-[(S)-1-phenylethyl] ethanamine.     

A Convenient Method for the Asymmetric Synthesis of KAD-1229

A new method for preparation of the potent hypoglycemic KAD-1229 was developed.The key step of this method is diasteroselective alkylation in high optical purity and good yield by using easily available Oppolzer‘s camphor sultam as chiral auxiliary.     

Convenient Synthesis of 7-Bromo-tetrahydro-1,5-benzodiazepin-2-ones

Treatment of 5-acyl-2,3,4,5-tetrahydro-1H-1,5-benzodiazepin-2-ones with bromine in the presence of the sulfuric acid afforded products to be brominated exclusively in the aromatic ring at position 7.     

A Convenient Synthesis of Novel Meldrum＇s Acid C60 Fullerene Derivatives

A series of novel Meldrum＇s acid C60 derivatives were prepared in moderate yields from a convenient one-pot reaction of C60, the Meldrum＇s acid derivatives, 12 and 1,8-diazabicyclo-[5,4,0]-undec-7-ene （DBU） in toluene at room temperature under nitrogen atmosphere. All the new compounds were fully characterized by the spectral data and elemental analysis. A carbene intermediate mechanism was proposed for this reaction.     

Convenient One-Pot Synthesis of 1,2,3,4-Thiatriazoles Towards a Novel Electron Acceptor for Highly-Efficient Thermally-Activated Delayed-Fluorescence Emitters

A novel and unexpected convenient one-pot synthesis of 1,2,3,4-thiatriazoles has been discovered while investigating the classical tetrazine “Pinner synthesis”. The synthetic route starts from commercially-available nitrile derivatives and gives good to high yields (51–80 %) with no need to isolate any thioacylating agents. The crucial impact of the solvent on the outcome of the modified “Pinner synthesis” is moreover examined and discussed. Using this new synthetic route, a novel donor-acceptor thiatriazole derivative has been prepared, which exhibits prominent thermally-activated delayed fluorescence (TADF) in both solution and film. The photoluminescence quantum yield (PLQY) in methylcyclohexane (MCH) and Zeonex (a cyclo olefin polymer) in oxygen-free conditions were determined to be 76 and 99 %, respectively. This work provides an efficient and practical synthetic approach to functionalized 1,2,3,4-thiatriazole derivatives, and will noticeably facilitate the application of 1,2,3,4-thiatriazole as an electron acceptor in organic electronics.     

Convenient Synthesis of Dicyclohexyldithiophosphinic Acid

Dicyclohexyldithiophosphinic acid was synthesized by a three-step strategy through the Grignard reaction of PSCl₃ with cyclo-C₆H₁₁MgBr and the P-P bond-cleavage reaction of the intermediate. The ¹H NMR data of ammonium dicyclohexyldithiophosphinate 4 and dicyclohexyldithiophosphinic acid 5 were characterized by ¹H-¹H correlation spectra.     

Simple, Mild and Convenient Synthesis of Two Novel N-Dichloro-acetyl Oxazolidines and their Biological Activities

Two N-dichloroacetyl oxazolidines were synthesized with a simple, mild and convenient method. All the compounds were characterized by IR, ^1HNMR and elemental analysis. The preliminary biological test showed that the compounds protected maize against injury by some herbicides to some extent.     

Convenient, Efficient One-Pot Synthesis of Ferrocenylcyanide

In asymmetric catalysis, chiral (central chiral, planar chiral, axial chiral) ferrocenylligands is one of the most successful class of auxiliaries in recent years, and some ofthem have reached the stage of industrial applications'. But many challenges remain forthe synthesis of the intermediate. One of them is how to get ferrocenylcyanide I directlyfrom ferrocenecarboxyaldehyde 2, which can be easily prepared according to thecorresponding literature2. As far as known, I is an important interm…     

简便合成二酰基二硒醚

芳基硒代酰胺与酰氯以1∶1的摩尔比在氯仿溶液中作用, 可以较高的产率得到二酰基二硒醚, 而芳基硒代酰胺与酰氯以1∶2的摩尔比反应时则生成二酰基硒醚. 提出了反应可能的机理.     

Novel and Convenient Synthesis of Benzofurans from Dihydrocoumarins

7‐Hydroxy‐3,4‐dihydrocoumarin‐4‐carboxylic acid ( 7 ), conveniently prepared from m‐resorcinol and maleic anhydride, was surprisingly transformed by acid anhydride and pyridine into the corresponding ketone, 4‐alkanoyl analog 11 . The latter reacted in turn with acidic alcohol yielding benzofuran‐3‐yl‐acetic ester 16.     

A Convenient Synthesis of Novel Mercapto-Ended Azobenzene Derivatives

Treatment of the product from the Diazo-Coupling reaction of p-alkylaniline with 1,3-dibromopropane in THF affords intermediate compounds n-C_nH_2n+1AzoO(CH₂)_mBr. Subsequent treatment of these intermediate with thiourea in ethanol at reflux temperature leads to the desired azobenzene derivatives, n-C_nH_2n+1AzoO(CH₂)_mSH (n=4,6,8,10,12; m=3,5), in good yield. The structure data of these new compounds was presented in detail.     

A Convenient One-Pot Synthesis of Di-t-butylphosphinic Chloride

A convenient one-pot synthesis of (t-Bu)₂P(O)Cl (1) from m-chloroperbenzoic acid and (t-Bu)₂PCl is described. The byproduct m-chlorobenzoic acid is neutralized by addition of Et₃N. Complex 1 crystallizes in the monoclinic space group P2₁/c (No. 14), with a = 5.9637(2) Å, b = 11.4734(4) Å, c = 16.2400(5) Å and β = 107.7160(14).     

氧杂三螺环化合物的简便合成

以环酮和季戊四醇为原料,磷钨酸为催化剂,在甲苯中回流分水反应合成了系列氧杂三螺环化合物（3a~3h）,其中5,9,14,17-四氧杂三螺［3.2.2.3¹⁰.2⁷.2⁴］十七烷（3a）和7,11,18,21-氧杂-3,15-二硫杂三螺［5.2.2.5¹².2⁹.2⁶］二十一烷（3f）为新化合物,其结构经¹H NMR, ¹³C NMR和HR-MS(ESI)表征。并以3c的合成为模板反应,对反应条件进行了优化。     

Convenient Synthesis of D-Talose from D-Galactose

The rare and expensive D‐talose was conveniently synthesized from readily available D‐galactose in four steps with an overall yield of 58%. The key step was the inversion of equatorial 2‐OH of galactose to the axial one by S_N2 reaction under the modified Lattrell‐Dax reaction conditions.     

A Novel and Convenient Synthesis of Coenzyme Q1

Abstract

A convenient and efficient synthetic route to Coenzyme Q₁ (6) starting from 3,4,5‐trimethoxytoluene (1) is described. The key features of this synthesis include the Diels–Alder reaction of 2,3‐dimethoxy‐l,4‐benzoquinone (3) with cyclopentadiene and the introduction of a C₅ side chain to 4,5‐dimethoxy‐2‐methyltricyclo[6.2.1.0^2,7]undeca‐4,9‐diene‐3,6‐dione (4) under mild conditions, (6) was obtained in overall 60% yield.     

An Efficient Large Scale Synthesis of 2-Methoxytetrahydrophenanthridine.

A practical and high yielding synthesis of 2-methoxy-7,8,9,10-tetrahydrophenanthridine suitable for large-scale preparation is described.     

A Convenient and Stereospecific Synthesis of (Z)-Benzylidenephthalides

Several 3-benzylidenephthalides have been isolated from natural sources1-2. Some of them are known to possess useful biological activity1 and are also valuable intermediates3 for the synthesis of naturally occurring biologically active compound. Most of the natural 3-benzylidenephthalides exist in the (Z)-configuration. Synthe-tic methods for construction of a 3-benzylidene-phthalide skeleton have been developed4. Some of these methods for synthesizing highly oxygen-functionalized compound…     

Efficient and Convenient One-Pot Synthesis of Dioxadiazaphophepines

The reaction of vicinal dioxime with sodium hydride in dry THF followed by addition of dichlorophosphates or dichlorothiophosphates yields 2-oxo-1,3,4,7-dioxadiazaphosphepines and 2-thioxo-1,3,4,7-dioxodiazaphosphepines in moderate to good overall yields. The products are characterized by elemental analyses, molecular weights and spectral (IR, ¹H, ¹³C and ³¹P NMR) studies. A salt elimination route is used for the synthesis of titled heterocycles.     

An Efficient and Convenient Cyclization Method for the Synthesis of Flavans

Flavansrefertoalargegroupofnaturallyoccurringcompoundspossessinga2-phenyl-chromannucleus.Naturallyoccurringflavansexhibitanumberofimportantbiologicalactivitieswhichifexploitedproperly,mayleadtovaluablenewdrugsoragrochemicals'.Inflavansynthesis,thekeystepistoconstructthe3,4-dihydrobenzopyranring-Variousmethodshavebeendevelopedfortheringformation,butmostoftheminvolvemultiplestepsandgivelowoverallyields2.Inthispaper,BF3wasusedforthefirsttimeasanefficientcatalysttoformthepyranringfroml,3-diaryIp…     

Convenient,Efficient Synthesis of Amide-Thioethers in Ionic Liquids

An improved method for the synthesis of carboxamide ligands containing thioether donor sites is described. This replaces the pyridine as the reaction medium used in the classical method by tetrabutylammonium bromide. The desired products, 1,4-bis[o-(R-2-carboxamidophenyl)]-1,4-dithiobutane, R = quinoline (1), furan (2), thiophene (3), pyridine (4), and pyrazine (5), were obtained in good yields and shorter reaction times.