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A variety of biaryl-2-carbaldehydes (III) is readily prepared by reaction of dienes (I) with cinnamaldehydes in the presence of allylamine and TFA.

A simple strategy for the synthesis of β-C-galactosyl ceramide and its new aza-variant analogue is described using the Horner–Wadsworth–Emmons reaction as the key step in combining the sugar and aglycone portions.

A metal-free one-pot protocol for the synthesis of different substituted 1,2-dihydropyridines is developed.

The attempt to produce an azasugar structure from substrate (I) under basic conditions causes a three-step sequence involving NH3-mediated ring opening, followed by spontaneous cyclization and unexpected double elimination.

The Cu-catalyzed N-arylation of phenylurea (I) or urea (IV) with arylboronic acids proceeds under mild reaction conditions and avoids the use of an expensive palladium catalyst or toxic phosphine ligands.

The simple procedure allows the selective oxidation of alkyl groups in aniline derivatives and methylcarbazole.

Review: synthesis, ring opening, reduction, substitution reactions, biological activities; 187 refs.

2,5-Dinitrofuran which can be easily prepared by nitration of 2-nitrofuran, on phase transfer catalysed SNAr reaction with phenol gave good yield of 2-aryloxy-5-nitrofuran. J. Heterocyclic Chem., (2011).

Optimized reaction conditions are developed which avoid the use of toxic phosphine ligands.

The ligand free coupling reaction of phenyl urea with different functionalized aryl halides in the presence of air stable Cu 2 O and t -BuOK as a base gives symmetrical and unsymmetrical diarylureas in relatively high yields. This method is milder than the palladium catalyzed arylation and avoids the use of toxic phosphine ligand.

The products are obtained in good to excellent yields with high purity and without detectable racemization.

via a multicomponent reaction using triethylammonium acetate as catalyst and reaction medium

A convenient protocol is presented for the cyclization of dipeptidyl thiosemicarbazides (III).

A convenient method has been developed for direct conversion of nitriles to amidines in high yields. The method can also be applied to the preparation of guanidines from N-alkyl cyanamides.

[reaction: see text] Highly substituted bicyclo[3.2.1]octadiene building blocks are easily prepared from tetrachloro- or tetrabromocyclopropene through reaction with cyclic dienes. These polyhalogenated derivatives can serve as precursors to a variety of functionalized bridged bicyclic compounds. Herein, we report on the generation and reaction of electrophilic species with silver ion.

This article reviews recent developments in the design of polyvalent ligands for in vivo applications. Topics discussed include the design of polyvalent inhibitors of toxins and viruses, the use of polyvalency for targeted drug delivery and imaging, and applications of polyvalency for enhancing or suppressing immune responses.

We have been interested in exploiting the highly functionalized oxabicyclo[3.2.1]octadienes that are produced by the cycloaddition of furan and tetrabromocyclopropene as synthetic building blocks. As part of this program, we have prepared non-racemic derivatives of these adducts containing an α,β-dibromoenone moiety embedded in the bicyclic framework. Elaboration of this unit has been realized through substitution and palladium-catalyzed cross-coupling reactions. Formation of bicyclodecenes has also been accomplished by a chromium-nickel-mediated ring closure. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

It has been known for several decades that a highly functionalized family of tetrahalobicyclo[3.2.1]octadienes are readily available through the cycloaddition of furan or cyclopentadiene with either tetrachloro- or tetrabromocyclopropene. However, the application of these highly functionalized building blocks in synthesis has remained relatively unexplored in relation to their better-known counterparts derived through oxyallyl cation additions. As a first step toward utilizing these highly versatile intermediates in synthesis, a study of the addition of various nucleophiles to the halogenated nucleus has been conducted. It has been found that these halogenated systems are amenable to a wide range of functionalizations in high yields and with good selectivities.