Stereoselective Synthesis of cis-1, 2-cyclopropane Derivatives

IntroductionNumeroussyntheticmethodsofcyclopropanationhavebeenstudied[l1,butmostofthemarenon-stereoselective,oritsproductisthethermodynamicallystableonewithl,2-transconfiguration.Thestereoselectivesynthesesof1,2-cisisomersofcyclopropanederivativesareseldomseeninliterature.Hereinastere-oselectivecycloporpanationviathereactionofarsenicylidewithe1ectrondefi-cientalkenesisreportedinthispaper.ResultsandDiscussionCarbomethoxymethylenetriphenylarl,oritsarsoniumbromideinthepresenceofK,CO,reactswith2…     

Synthesis and Crystal Structure of 2-Amino-1, 1-diferrocenylethanol

2-Aminoalcohols are useful intermediates in organic chemistry, for example, they serve for the synthesis of various heterocycles1, chelate complexes2, and for the ring expansion of cycloalkanones3. 2-Aminoalcohols containing ferrocene as bidentate ligand may be converted into multinuclear compounds. Several methods for the preparation of 2-aminoalcohols have been developed including reduction of the trimethylsilyl cyanohydrins4 or β-nitromethyl alcohols5 and treatment of the epoxides with a…     

Synthesis and Crystal Structure of 2-Amino-I, 1-diferrocenylethanol

2-Amino-l,l-diferrocenylethanol 2 was prepared by reduction of trimethylsilylcyanohydrin ether of diferrocenyl ketone. The crystal structure of 2 was further defined by X-raydiffraction.     

Facile Synthesis of 1, 2-Diazepine Derivatives under Microwave Irradiation

An efficient and convenient synthesis of 3, 5, 7-triaryl-4H-1, 2-diazepine from 2, 4,6-triarylpyrylium salts and hydrazine in water under microwave irradiation is reported. The same reaction can be conducted using 2, 4, 6-triarylthiopyrylium salts and hydrazine.     

Synthesis of 2-Arylimidazo[1, 2-a]pyrimidines in Ionic Liquids

Room temperature ionic liquids were used as a “green“ recyclable alternative to conventional solvents in the synthesis of pharmaceutically useful compounds 2-arylimidazo[1, 2-a]pyrimidines through Tschotschibabin reaction of a-bromoacetophenones with 2-aminopyrimidine in good yields.     

One-pot Synthesis of 4-Trifluoromethyl-l,2-dihydropyrimidines

4-Trifluoromethyl-1,2-dihydropyrimidines were synthesized in moderate yields by the one-pot reaction of 4-ethoxy-1,1,1-trifluoro-3-buten-2-one, aldehydes and ammonia catalyzed by zinc chloride under mild conditions.     

Grignard Addition to Quinoxalinium Salt： Synthesis of 1, 2-Dihydroquinoxaline and 1, 2, 3, 4-Tetrahydroquinoxaline Derivatives

Nucleophilic addition of organometallics to imines or iminium ion has received greatattention in recent years, especially in the field of asymmetric synthesis1. Addition ofthe nucleophilic reagents to quinoxalines was proved to be a useful method for thes…     

Solid Phase Synthesis of 1, 4-Disubstituted 1, 2, 3-Triazole from Polystyrene-supported Selenium Resin

The preparation of diverse libraries of organic compounds is an important facet of modern drug discovery programs. One of the most commonly employed method in library production is solid phase organic synthesis (SPOS)1. Experience has shown that the compo…     

A New and Efficient Synthesis of 2H-3, 1-Benzoxazine Compounds

2H-3, 1-Benzoxazine heterocyclic compounds are a series of potent nonsteroidal pro- gesterone receptor agonists1-3 and have many other applications such as carbonaceous electrode, plant growth regulating and anti-stress activities4-6, etc.. Comparing to other benzoxazine series, such as 1, 4-benzoxazine, 2H-1, 3-benzoxazine, etc., little attentions have been paid for this series of compounds. There is only one method for the preparation of 2H-3, 1-benzoxazine, e.g. cyclocondensation of o-amin…     

Synthesis of extended, π-conjugated isoindolin-1-ones

The synthesis and characterization of extended, conjugated molecules containing isoindolinone units was explored. Nucleophilic cyclizations between an amide and an alkyne were found to be an efficient method of producing the desired isoindolin-1-ones in high yields. A variety of derivatives were synthesized, demonstrating that a number of structural alterations could be made while maintaining good regio- and stereospecificity in the cyclized product.     

Synthesis and Crystal Structure of 1-Methylsulfinyl-1-methylthio-2-cyano-2-phenylethylene

1　ＩＮＴＲＯＤＵＣＴＩＯＮＤｉｔｈｉｏａｃｅｔａｌｓ[1 3]ｈａｖｅｄｅｍｏｎｓｔｒａｔｅｄｔｈｅｉｒｐｏｔｅｎｔｉａｌｆｏｒｔｈｅｓｙｎｔｈｅｓｉｓｏｆｈｅｔｅｒｏｃｙ ｃｌｅｓ,ｔｈｅｒｅｆｏｒｅ ,ｔｈｅｉｒｓｙｎｔｈｅｓｉｓａｎｄｒｅａｃｔｉｏｎｓｈａｖｅａｔｔｒａｃｔｅｄｍｕｃｈａｔｔｅｎｔｉｏｎ ,ｂｕｔｖｅｒｙｌｉｔｔｌｅｈａｓｂｅｅｎｒｅｐｏｒｔｅｄａｂｏｕｔｔｈｅｏｘｉｄａｔｉｏｎｏｆｄｉｔｈｉｏａｃｅｔａｌｓ[4].Ａｃｃｏｒｄｉｎｇｔｏｔｈｅｐｒｅｖｉ ｏｕｓｒｅｐｏｒｔ,ｔｈｅｏｘｉｄ…     

Improved Electrochemical Synthesis of Nitro-substituted 1-Aryl-2-pyrrolidinecarbonitriles

Anodic cyanation is expected to provide a promising method for synthesis of nitriles by reason of its positional reactivity and simple operation1. Within our ongoing interest in cyano group incorporation into small heterocyclic ring systems2, 3, the elect…     

Synthesis and Catalytic Application of Chiral 1, 1-Binaphthyl Polymers

Polymer-supported reagents and catalysts have attracted considerable attention as they offer alternative methods to separate and reuse expensive and often toxic chemicals1. Traditionally, the polymer-supported chiral catalysts are prepared by anchoring highly enantioselective monomeric catalysts to flexible and sterically irregular polymer supports. Because of the stereo-irregularity and flexibility of the traditional polymeric chiral catalysts, their catalytic sites do not have well-defined…     

Synthesis of 3-Phenyl-6-formyl-3, 4-dihydro-2H-1, 3-benzoxazine

Benzoxazine is a novel class of thermosetting resins, which possesses lots of outstanding properties such as no by-products and near-zero shrinkage during polymerization as well as good molecular design flexibility1-2. Furthermore, polybenzoxazines (PBZs)…     

The Synthesis of 2, 4, 6-Triisopropyl-1, 3, 5-trioxane Catalyzed by Ionic Liquids

The synthesis of 2, 4, 6-triisopropyl- 1, 3, 5-trioxane with high yield and desirable selectivity from solvent-free cyclotrimerization of isobutyraldehyde catalyzed by ionic liquids was reported in this work.     

Synthesis and Conformational Analysis of 1, 2-Anhydro-3, 4-di-O-benzyl-6-deoxy-α-D-glucopyranose

Abstract

The title 1, 2-anhydro sugar (10) was synthesized from methyl 4, 6-O-benzylidene-α-D-glucopyranoside or from 1, 2-O-ethylidene-α-D-glucopyranose. The key intermediate for the synthesis was 2-O-acetyl-3, 4-di-O-benzyl-6-deoxy-β-D-glucopyranosyl fluoride (8)which was transformed into the target compound by ring closure with potassium tert-butoxide. Calculations by the modified Karplus equation from vicinal coupling constants of 10 suggested that the conformation of 10 was almost an ideal ⁴ H ₅ for the pyranose ring. Conformational analysis for the 1, 2-O-(R)-ethylidene intermediates 17 and 20 revealed that their pyranose ring basically adopted a B₂,₅ conformation.     

Synthesis, Crystal Structure, and Biological Activities of 2-Oxo-2-aryl-1 - （ 1,2,4-triazol-1 -yl ） ethyl phenylcarbamodithioate

IntroductionAs an important type of fungicide, compoundscontaining 1,2,4-triazole groups have attracted muchattention because they exhibit a certain fungicidal acti-vity againstPuccinia reconditeand also play a role inroot-growth regulation[1—3]. However…     

Synthesis and cytotoxicity of dinuclear platinum(Ⅱ) complexes of (1S, 3S)-1, 2, 3, 4-tetrahydroisoquinolines

A series of novel dinuclear platinum(Ⅱ) complexes with (1S, 3S)-1,2,3,4-tetrahydroisoquinolines as the ligands were synthesized as potential anticancer agents in several steps starting from commercially available L-DOPA. The cytotoxicities of the series of dinuclear platinum(Ⅱ) complexes of tetrahydroisoquinoline were tested against HCT-8, BEL-7402, A2780, MCF-7, Hela, A549 and BGC-823 cell lines by the MTT test. These complexes showed selective inhibition activity against cisplatin-insensitive cell line Skov3.     

Synthesis of 1, 4-Bis[3-N-propionyl-2-aryl-1, 3, 4- oxadiazoline-5-yl]phenylenes

1, 3, 4-Oxadiazoline derivatives are found to possess significant biological activities such as antifungal1, insecticidal2, CNS depressant3-5, anticonvulsant effects and plant growth accelerator. They are highly important heterocycles, and have been used …