An expedient synthesis of salviadione

An expedient synthesis of the alkaloid salviadione, the only to date isolated naturally occurring 1H-benzo[def]carbazole is described. The key step in the synthesis is a palladium-catalyzed, carbon monoxide-mediated reductive N-heterocyclization of a nitroarene with an adjacent alkene.     

An expedient synthesis of homophthalimides

The six-membered heterocyclic subunit of homophthalimides can be obtained by a direct, hitherto unprecedented, radical cyclisation onto an aromatic ring starting from a xanthate precursor.     

An expedient synthesis of mellitic triimides

Heating of the solid ammonium salts obtained from treatment of mellitic acid with 3 equiv of a primary amine yields trisubstituted mellitic triimides via dehydration and imide ring closure. This surprisingly simple synthetic approach is amenable to incorporation of alkyl, aryl, and amino acid ester substituents, thereby opening broad access to a family of C(3)-symmetric organic electron acceptors.     

An expedient synthesis of substituted indoles

Condensation of carboxylic acid esters with organodilithium reagents derived from N-trimethylsilyl-o-toluidine or N-trimethylsilyl-o-ethyl aniline affords substituted indoles.     

An expedient asymmetric synthesis of platencin

A short and efficient synthesis of enone 3, a key intermediate in the total synthesis of platencin (2), based on an intramolecular Diels-Alder reaction is described.     

An expedient synthesis of ellipticine via Suzuki-Miyaura coupling

A simple and efficient total synthesis of ellipticine was developed via the Suzuki-Miyaura coupling of sterically sensitive 2-hydroxybenzeneboronic acid with a multifunctional aryl halide using Pd(OAc)₂ as a catalyst and Cu(OAc)₂·H₂O as an additive in DMSO/H₂O as a key step followed by double N-arylation and cyclization.     

An expedient synthesis of (+)-quinolactacin A2

An expedient synthesis of quinolactacin A2 from N-methylisatoic anhydride and N-Boc-(2S,3S)-isoleucine has been achieved. The key step involves the Friedländer-type annulation of isatoic anhydride and β-ketoester derived from isoleucine.     

An expedient synthesis of diversified pyrrolizines and indolizines

A general and rapid synthesis of new families of pyrrolizines and indolizines in good overall yields via an intramolecular [3+2] cycloaddition reaction is described. Diversity of substitutions can be achieved by the appropriate choice of readily available starting materials. The experimental procedures are straightforward and are performed under neutral conditions. New syntheses are also described for the preparation of N-propargylic 2-amino-benzaldehydes and S-propargylic 2-thiobenzaldehydes.     

An expedient synthesis of 2,5-disubstituted-3-oxygenated tetrahydrofurans

Single enantiomer 2,5-disubstituted-3-oxygenated tetrahydrofurans are synthesized in as little as four steps from a commercially available epoxide. The key steps are homoallylic alcohol epoxidation, palladium-catalysed alkoxy-carbonylation-lactonisation and Mitsunobu inversion. The protocol is applied to the formal total syntheses of (+)-kumausallene, (6S,7S,9R,10R)-6,9-epoxynonadec-18-ene-7,10-diol and the core of lytophilippine A.     

An expedient synthesis of tetrakis(cyclopropylmethyl)methane

Synthesis of tetrakis(cyclopropylmethyl)methane, a new symmetric product has been described using the radical mediated gem-diallylation of cyclopropylmethyl xanthate as a key step and its single crystal X-ray analysis established its C2-symmetry.     

An expedient synthesis of (±)-centrolobine

An expedient synthesis of the antibiotic natural product centrolobine is reported, the key step being the one pot, multi-component construction of a tetrahydropyran-4-one via a ‘revisited’ Maitland-Japp reaction.     

An expedient one-pot synthesis of benzophenone Schiff bases from benzene

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An expedient one-pot synthesis of novel 10-substituted 9-aminophenanthrenes

An efficient synthesis of 9,10-disubstituted phenanthrenes is described in this Letter. These novel useful building blocks were obtained in a one-pot reaction including Suzuki-Miyaura cross-coupling followed by a Dieckmann-Thorpe ring closure under microwave irradiation. The selection of the appropriate reagents and the optimal reaction conditions to isolate the intermediate biphenyl compound or the final substituted phenanthrenes in high yields will be discussed in this Letter.     

An expedient synthesis of peptidyl N-alkylamides by "HOPE" strategy

We have developed an expedient approach,"HOPE"(hybrid orthogonal protocol with ease) strategy for the synthesis of peptidyl N-alkylamides.This new strategy was characterized by following points:incorporating Boc and Fmoc protocols together on Merrifield resin,removal of SPG(side-chain protecting groups) without the damage of linker structure on the resin,and the ammonolysis of linker as the last step could achieve the introducing N-alkylamide structure into C-terminal and releasing product from resin-support simultaneously.In present work,eight peptidylamides with different alkylsubstitution at C-terminal were conveniently synthesized by HOPE strategy.     

An expedient synthesis of 5-alkynyl-6-aryl-2,2′-bipyridines

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An expedient one-pot sequential five-component synthesis of highly substituted spiro-pyrrolidine heterocycles

An expedient one-pot sequential five-component synthesis of highly substituted pyrrolidine heterocycles involving [3+2]-cycloaddition of azomethine ylides as the key step is described. The protocol provides a mild reaction condition, high yield of the products, high regioselectivity and operational simplicity to assemble complex structural entity in a single operation. The structure of the product was confirmed by spectroscopic and single crystal X-ray analysis.     

Tandem molybdenum catalyzed hydrosilylations: an expedient synthesis of beta-aryl aldehydes

The synthesis of beta-aryl aldehydes utilizing a tandem molybdenum catalyzed hydrosilylation is described. This new functional group interconversion provides an efficient method for the two-carbon homologation of aryl aldehydes.