A Facile Synthesis of 3,4‐Benzo‐β‐carbolines

Abstract

A convenient method for the synthesis 3,4‐benzo‐β‐carbolines (10) from the corresponding N‐phenylsulfonyl‐3‐bromo‐N′‐arylisogramines (5) via radical mediated cyclization methodology has been reported.     

Gallium Triiodide–Catalyzed Organic Reaction: A Convenient Procedure for the Synthesis of Coumarins

Abstract

Gallium triiodide, which was generated in situ by the reaction of gallium metal and iodine, was used as an efficient catalyst in the Pechmann condensation of phenols with ethyl acetoacetate, leading to the formation of coumarins. The reaction proceeded in dichloromethane at room temperature with good to excellent yields.     

A Convenient Method for the Synthesis of Distamycin Analogue

A novel distamycin analogue was synthesized by chloroform reaction and DCC/HOBT coupling reaction without using amino protection and deprotection.     

A Convenient Synthesis of β-Ketosulfoxides

β-Ketosulfoxideshaveattractedmanyorganicchemistsbecauseoftheirwideuseinsynthesisofketones,a-ketols,glyoxals,a-ketoacids,glycols,a-hydroxyacidsandsoculGenerally,6-ketosulfoxidescanbepreparedbythereactionofesterwithsulfoxidel',acylchloridewithsulfoxi...     

Cerium(IV) Ammonium Nitrate–Mediated Oxidation of Mono-aryl-substituted Methylenecyclobutanes: A Convenient Method for the Synthesis of Spirocyclobutyl-1,2-dioxethanes

Cerium(IV) ammonium nitrate (CAN)-mediated oxidation of methylenecyclobutanes was investigated. Compared with the similar reactions of methylenecyclopropanes, the reaction products were quite different. Instead of the desired ring-enlarged product cyclopentanones, a cyclobutyl ring-intact product, spirocyclobutyl-1,2-dioxethane, was obtained. The structures of these spiroheterocycle-containing compounds are interesting, and the reactions are potentially valuable in both organic synthesis and mechanism research.

A Facile Synthesis of Tetracycles of the γ-Lycorane Type

When an attempted application of the general scheme of alkaloid synthesis, based on the partial hydrogenation of 1 -alkyl-3-acylpyridinium salts and acid-induced cyclization of the resultant 2-piperideines,² to the construction of an Amaryllidaceae alkaloid system failed in the cyclization step, i.e. the transformation of dihydroisoquinoline 4a (prepared by the treatment of ester 2a ³ with 5-bromo-2 -pentanone ethylene ketal, followed by hydrogenation of the salt over palladium-charcoal) into a tricyclic ketal ester,⁴ an alternate, route of synthesis still utilizing a previously prepared isoquinoline precursor (3b) was investigated. The initial observation of the easy conversion of 3b into N-methyl (1a) and O-ethyl products (2b) was helpful in this connection.     

A New Convenient Synthesis of Pyridine-N-oxides

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A Facile Synthesis of Benzoxazolyl Cyclopropanes

2′-Benzoxazolyl substituted cyclopropane derivatives were synthesized in the yield of 73-89% from the reaction of telluronium ylides with chalcones.     

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.     

Facile Synthesis of Poly(hydridocarbyne): A Precursor to Diamond and Diamond‐like Ceramics

Polycarbynes have previously been shown to be polymeric precursors to diamond and diamond‐like carbon. Here, we report an incredibly simple method for producing one of these polymers, poly(hydridocarbyne). The method simply requires chloroform, electricity, a solvent and an electrolyte. Since the polymer is soluble, the production of diamond objects of any shape is feasible. It is hoped that the ease of the synthesis will make these types of polymers accessible to scientists from all disciplines and that the potential applications for this material, which range from electrical to biomedical, are finally realized.     

Room‐Temperature Ionic Liquid–Promoted Williamson's Synthesis of Ethers: A Facile Synthesis of Diaryloxymethanes

A simple and efficient method has been developed for the synthesis of phenolic ethers using room‐temperature ionic liquid, not only as solvent but also as promoter. Ionic liquid was recycled and subsequently reused without any loss of the product.     

A Convenient Synthesis of Protected α-Hydroxyacetaldehydes

Starting from 2, 3-O-isopropylideneglycerol (1), a general procedure for the preparation of protected α-hydroxyacetaldehydes has been developed.     

A Convenient Method of Synthesis of Ferrocenylethynyl Ketones

It is well known that molecules possessing extensive conjugated π-electron systems exhibit large non-linear optical properties,[1,2] but the compounds of ferrocenylethynyl ketones have not been reported so far. We now reported preparation of some ferrocenylethyl ketones. These new ethynylketones containing ferrocenyl were prepared conveniently via coupling reaction catalyzed by PdCl2(PPh3)2/PdBzCl(PPh3)2-CuI from ferrocenylethyne and acyl chlorides. This coupling reaction proceeded smoothly in argon and free-water atmosphere at room temperature and gave coupling products in satisfactory yields. All products were characterized by 1H NMR, MS, IR and UV spectra.     

A Convenient Synthesis of β-Amino Acid

We have reported the reductive cleavage of azlactones¹ and phenylhydrazones² of carbonyl compounds in the presence of a suitable catalyst. In this paper a general method involving a one step synthesis of β-amino acid^3,4, in good yield, through catalytic reduction of oximes of α-β-unsaturated acid is reported. This method involves the reaction of α, β-unsaturated acid with hydroxylamine hydrochloride in the presence of sodium acetate. Markovnikov's rule is followed in the synthesis of oximes of α, β-unsaturated acids.     

Synthesis of the Precursor of Tetrasaccharide from Laminin

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A Concise and Stereoselective Synthesis of the Cathasterone''''s Side Chain

A concise and stereoselective synthesis of cathasterone's side chain using methyl isopropyl ketone 3 as the fragment is described.     

A Facile and Green Synthesis of Sulforaphane

Sulforaphane (1, SFN), 4-methylsulfinylbutyl isothiocyanate, was considered as the most potent inducer of phase II enzymes proteins [glutathione transferases (GSTs) and NAD(P)H: quinone reductase (QR)] selectively, and strong inhibitor of phase I enzymes …     

Facile Synthesis of Isoamericanol and Isoamericanin A

A number of benzodioxane compounds were synthesized using the palladium-catalyzed etherification of aryl halides by employing triphenylphosphane ligands. This method was used as key step in the synthesis of isoamericanol A and isoamericanin A.     

A Convenient Procedure for the Synthesis of 6-O-Mono-Phosphate β-Cyclodextrins

Abstract

The synthesis of β-cyclodextrin derivatives bearing one phosphate group on the primary rim is reported. These compounds were prepared in good to excellent yields, by reacting β-cyclodextrin with dialkyl chlorophosphates in the presence of 4-dimethyl amino pyridine (DMAP) catalyst and dimethylformamide (DMF) as solvent. The methodology described is highly selective and the purification of the title compounds is simple, because difficulties due to phosphate regioisomers mixture are avoided.