Carbopyronine荧光染料中间体的有效合成方法

在非质子路易斯酸的辅助下高收率的合成了Carbopyronine荧光染料中间体2,7-双二甲氨基-9,10-二氢-9,9-二甲基蒽环。反应关键步骤是路易斯酸辅助下的环化反应,考查了几种路易斯酸的效果。确立了环化反应的最佳条件为： 2.5mol的路易斯酸与1mol的叔醇2在0 ˚C反应6 h,再于室温下反应10 h。     

A More Efficient Synthetic Route to Perylene-porphyrin Arrays

We present an efficient synthetic route towards two kinds of perylene-porphyrin arrays. Starting from 5, 10, 15, 20-meso-tetraphenylporphyrin, two novel 9a and 9b were designed and synthesized with 40.3% and 35.1% yield, respectively.     

New Efficient and Flexible Synthetic Route to Emivirine and Its Analogs

A revised synthetic route to Emivirine (MKC‐442) via properly substituted β‐keto ester converted from Meldrum's Acid was developed. This method could be applied to the synthesis of a variety of MKC‐442 analogues and open the way for their systematic biological evaluation.     

Novel Synthetic Route to Fluoxetine

Racemic fluoxetine was synthesized from 3-benzoylpropionic acid in five steps in 54% overall yield.     

Synthetic Route to Ergot Alkaloids

Rye is sometimes infected by a fungus called Claviceps purpurea. The term ergot designates the dark, brown, tuberous bodies which can be collected before or during harvesting and represent one of the most remarkable drugs of our therapeutic arsenal. Actually, the most significant alkaloids are metabolic products of these fungi. We elaborated three alternative total synthetic pathways to construct the ergoline skeleton, one of which – suitable for scaling up – finally resulted in (+)‐lysergic acid ( 32a ) and α‐ergocryptine ( 1 ) (Schemes 5 and 6).     

A Facile Synthetic Route to L-Phosphinothricin

Phosphinothricin, the active ingredient of the well known broad-spectrum herbicideglufosinate-ammonium, is a naturally occurring amino acid possessing the uniquemethylphosphinate moiety, and its strong herbicidal activity has been attributed to anability to inhibit glutamine synthetase in plants and bacteria1. Further research showedthat L-enantiomer of phosphinothricin was the carrier of the activity, whereas the D formonly had a small action2, therefore the stereoselective synthesis of L-pho…     

A Novel Synthetic Route to Furan-Lignans

Three naturally occurring furan–lignans and two analogs have been synthesized by a short and efficient route starting from the corresponding aryl acid. The selective reductive removal of allylic hydroxy by palladium oxide in a mixed solvent of THF–CHCl₃ was employed as the key step.     

New Synthetic Route to Polyhedral Organylsilsesquioxanes

Hydrosilation of methylenecyclohexane and hex-1-ene by octa(hydridosilsesquioxane) catalysed by hexachloroplatinic acid is a new route to polyhedral organylsilsesquioxanes. Quantitative yield of octa(cyclohexylmethylsilsesquioxane) is reached. This reaction opens a vast field of yet unknown polyhedral silsesquioxanes.     

New Synthetic Route to Pummerer's Ketone

Pummerer's ketone 1 is obtained with an overall yield of 55 % by the following sequence: Claisen rearrangement of an arylcyclohexylether 3; allylic oxidation of the methylcycloalkylphenolic derivative 4b, then spontaneous cyclisation during demethylation to give 2. 1 is obtained by dehydrogenation of 2. NMR data agree with a cis stereochemistry at C_4a and C _9b.     

Rapid Access to New Angular Phenothiazine and Phenoxazine Dyes

The synthesis of some new thiophenyl‐derivatized and furanyl‐derivatized phenothiazine and phenoxazine dyestuffs is described. This was achieved by two methods after the synthesis of 6‐chloro‐5H‐benzo[a]phenothiazin‐5‐one, 6‐chloro‐5H‐benzo[a]phenoxazin‐5‐one, and 6‐chloro‐5H‐naphtho[2,1‐b]pyrido[2,3‐e][1,4]oxazin‐5‐one intermediates via anhydrous base condensation reaction of 2,3‐dichloro‐1,4‐naphthoquinone with 2‐aminothiophenol, 2‐aminophenol, and 2‐aminopyridinol, respectively. The first method involved treatment of tributyl(thien‐2‐yl) or tributyl(furan‐2‐yl) stannane with chlorophenothiazine/chlorophenoxazine under mild basic chemical formula (CsF) and 1,4‐dioxane or toluene solvent at 80°C to supply dazzling yellow solid in high yields. In the second method, the catalytic system was pre‐activated in acetonitrile, followed by addition of coupling partners and K₃PO₄ to obtain high melting and variety of highly colored products in moderate to high yields. The reaction conditions were compatible with unprotected N–H and carbonyl functional groups. The intense colors of these dyes and their ease of re‐oxidation of Na₂S₂O₄‐reduced derivatives make them suitable as vat dyes. Also, they were found to be good colorants for textiles, papers, paint, ink, soap, polish, candle, and plastic materials.     

An Unusual and Facile Synthetic Route to Alumoles

Reaction of the aluminum dialkynyl LAl(CCR)₂ (L=N,N‐chelate ligand and R=organic group) with B(C₆F₅)₃ proceeds through an intermediate with Al???η²‐C≡C side‐on coordination to form the alumoles ( 2 , 4 , 6 ). A distinctive reaction pattern indicates a new facile synthetic route to aluminum‐containing heterocycles. The synthetic process is described, and the characterization of compounds and computational calculations were carried out. Furthermore, alumoles 2 and 4 exhibit an aggregation‐induced emission (AIE) of the bright yellow fluorescence.     

An Effective Synthetic Route to Ef5

EF5 (a 2-nitroimidazole containing an N-(pentafluoropropyl) acetamide substituent) is a very sensitive probe for quantifying the amount of hypoxia within cells; a much improved, short step, synthetic procedure is described for EF5, whose X-ray structure is also presented.     

A New Synthetic Route to 5-Isoxazolamines

5-Isoxaz0lamineshavebeenusedasintermediatesforthesynthesis0fderivatives0fantihistaminic,analgetic,antibacterial,insecticidal,herbicidalandfungicidalactivity'.Usuallytheyaresynthesizedbytheintramolecularcondensation0fhydr0xylamineand0-nitrilegr0up'.Otherapproaches,suchasreductivecyclizati0nofZ-a-cyano-6-nitroethylenesandIithiumaIuminumhydridereduction0f3-cyanooxazoleshaveals0beenrepoFted'-'.HerewerepoFtanewsyntheticrouteofthesecompounds.Ohn0andNaruse7havereportedthatthereactionof2-chlorocycl…