A facile synthetic route to new pyrazoloisoindolones

A facile method for the synthesis of new pyrazoloisoindolones via a Suzuki cross-coupling reaction using a pyrazolylboronic ester is described.     

A facile route to isoflavone quinones via the direct cross-coupling of chromones and quinones

A straightforward and efficient method for the palladium-catalyzed direct cross-coupling of chromones with various quinones has been developed to rapidly construct isoflavone quinone structural motifs.     

A facile Horner-Wadsworth-Emmons route to 2-quinolones

2-Quinolones are prepared from o-aminophenylketones by N-acylation with phosphonoalkanoylchlorides, followed by an intramolecular Horner-Wadsworth-Emmons olefination. The transformation proceeds under mild conditions, is generally applicable, gives good yields and can be performed either in two steps or as a one-pot reaction.     

A facile synthetic route for antineoplastic drug GDC-0449

In the current study a facile synthetic route for preparing antineoplastic drug GDC-0449 is investigated. Starting with pyridine-1-oxide and 1-iodo-3-nitrobenzene, the intermediate product 2-(2-chloro-5-nitrophenyl) pyridine was prepared by cross-coupling, deoxidation and halogenation. The final compound was then synthesised by reduction of the nitro group followed by amidation. This synthetic route avoids the use of unstable organometallic or organic boride compounds; it employs relatively inexpensive and bench-stable reagents, involves readily controllable reaction conditions, and achieves a relatively high yield.     

A facile route to phenyl, phenylsulfanyl and phenylselanyl substituted pyrano[3,2-c]chromenes

The synthesis of phenyl, phenylsulfanyl and phenylselanyl substituted pyrano[3,2-c]chromenes 4 is accomplished via cyclocondensation of 4-oxo-4H-chromen-3-carbaldehydes 1 with appropriately substituted acetic acids 2 under mild conditions. Further treatment of 4 with alcohol or water led to 5-alkoxy- and 5-hydroxy-2H,5H-pyrano[3,2-c]chromen-2-ones 5 and 6, respectively. Acid and thermal catalysed rearrangement of 4-6 gave 5-hydroxypyrano[2,3-b]chromen-2(10aH)-ones 7 and their subsequent substitution led to 5-alkoxyderivatives 8. Reaction of 4 with amides led to 5-acylamino or 5-phenylsulfonamino substituted 2H,5H-pyrano[3,2-c]chromen-2-ones 9. Reactions were performed under heating or microwave irradiation.     

A facile route to perylenequinone

Two-stage Ullmann and phenol coupling were effected in a singleoperation on methyl 5-bromo-1,2-dihydroxy-6,8-dimethoxynaphthalene-3-acetate to give dimethyl 5,8-dihydroxy-1,3,10,12-tetramethoxy-4,9-perylenequinone-6,7-diacetatewith ferric chloride as oxidant.     

A facile synthesis of 3-alkylchromanones and chromones

A simple and high yielding route to 3-alkylchromanones and 3-alkylchromones has been achieved from 3-alkyl-3-phenyl-sulphonyl-4-chromanones.

A simple and high yielding route to 3-alkylchromanones and 3-alkylchromones has been achieved from 3-alkyl, 3-phenylsulphonyl-4-chromanones.     

A facile synthetic route to (+)-allosedamine via hydrolytic kinetic resolution and olefin metathesis

A concise synthesis of (+)-allosedamine has been achieved using cobalt-catalyzed hydrolytic kinetic resolution (HKR) and ruthenium-catalyzed ring closing metathesis (RCM) as two key steps, in which HKR was used to introduce both stereogenic centers in the natural compound with a high degree of diastereomeric ratio and cyclization was carried out with the well developed RCM procedure.     

A facile and general route to 4-substituted-2 butenolides

Grignard reagents react with 7-oxabicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic anhydride and produce in high yields the corresponding substituted bicyclo-γ-butanolides. These lactones produce the title compounds by retro Diels-Alder reaction during distillation.     

A facile tandem carbene-ylide route to 2-fluoropyrrole derivatives

2-Fluoropyrroles were synthesised via 1,3-dipolar cycloaddition of iminiodifluoromethanides derived from corresponding imines and difluorocarbene to dimethyl acetylenedicarboxylate.     

A facile synthetic route to a third-generation dendrimer with generation-specific functional aryl bromides

The synthesis of three third-generation dendrimers that selectively carry one aryl bromide functional group in the first, second, or third generation, respectively, is described. These functions, regardless of their location, can be chemically modified by Suzuki cross-coupling chemistry with p-tert-butylbenzene boronic ester.     

A facile route to polysubstitutedN-benzyl pyroglutamates

[reaction: see text] Base-induced coupling/cyclization reactions of alpha-sulfonylacetamide with various ethyl (Z)-2-bromo-2-propenoates have been carried out. The polysubstituted pyroglutamate carbon skeleton, with three contiguous asymmetric centers, was built up in one step. A ring-closure mechanism is proposed for the reactions.     

A facile synthetic route to bimetallic ReI complexes containing two dppz DNA intercalating ligands

The synthesis of, and preliminary DNA binding studies on, bimetallic complexes containing two tethered DNA intercalating [(CO)3Re(dppz)]+ metal centres is reported.     

Studies on organophosphorus compounds 101. A facile synthetic route to trifluoromethylated aminophosphonic acids and phosphonopeptides

A series of dialkyl 1-(N-substituted amino)-2,2,2-trifluoroethylphosphonates was synthesized by Arbuzov-type reactions involving an N-substituted trifluoromethylimidoyl chloride and the appropriate trialkyl phosphite. The resulting C=N bond was successfully hydrogenated by NaBH₄CN treatment. The subsequent deprotection of the amino group was conducted either by hydrogenolysis with Pd black or by use of cerium ammonium nitrate, depending on the structure of the substituent on the amino function. The free amino group thus obtained underwent a coupling reaction with an aminoacyl chloride in the usual manner. © 1998 John Wiley & Sons, Inc. Heteroatom Chem 9:139–146, 1998     

A facile route to 4,5,6,7-tetrahydrothiophenes and benzothiophenes

2-Substituted tetrahydro- and cyclopentathiophenes 2 were produced in high yields by treatment of the semi-cyclic trisubstituted 1,4-diketones 1 such as 2-phenacylcyclohexan-1-one, 2-acetonylcyclohexan-1-one, and 2-phenacylcyclopentan-1-one, with Lawesson's reagent.     

A facile route to difunctionalized monosubstituted octasilsesquioxanes

A series of difunctionalized monosubstituted octasilsesquioxanes have been synthesized that bear ester, amino acid, alcohol, haloalkyl, or azido functional groups. These units are suitable nanobuilding blocks for the preparation of new organic-inorganic hybrid materials.     

A facile route to highly functionalized ketenimines

Summary A one-pot synthesis of highly functionalized ketenimines by reaction of alkyl isocyanides with dialkyl acetylenedicarboxylates in presence of 1,3-diphenylpropan-1,3-dione is reported.

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Ein einfacher Weg zu hochfunktionalisierten Keteniminen

Zusammenfassung Es wird eine Eintopfsynthese hochfunktionalisierter Ketenimine durch Reaktion von Isocyaniden mit Dialkylacetylendicarboxylaten in Gegenwart von 1,3-Diphenylpropan-1,2-dion beschrieben.

     

A facile convergent route to dendritic polyols

The synthesis of monodisperse dendrimers triggers a great challenge to the synthetic chemistry. Here, we reported a facile convergent approach to the synthesis of the first generation, six-directional ether-bond polyols with better controlled structures and ease of purification.     

A facile tetrahydrothiophene-catalyzed ylide route to vinyloxiranes

Access to vinyloxiranes using aldehydes and allylic bromides in the presence of 1-5 mol% tetrahydrothiophene is reported. Both aliphatic and aromatic aldehydes work well in this reaction and the catalyst loading could be reduced as low as 0.5 mol%.