(57) ABSTRACT Micro-cavity resonant sensors have outer surfaces that are functionalized using click chemistry, e.g., involving a cycloaddition reaction of an alkyne functional group and an azide functional group. A first polymer linking element binds to an outer surface of the micro-cavity and has an azide functional group, which bonds to an alkyne functional group of a second polymer linking e...

a series of 1,3-dipolar cycloaddition reactions are carried out using cyclodimers of simple nitrones and various dipolarophiles; substituted isoxazolidines are isolated and identified. it is proved that such cyclodimers, in solution, are in equilibrium with their corresponding nitrones and enamines. it is also concluded that aldocyclodimers are more potent than keto-cyclodimers in establishing ...

A series of functionalised aromatic boronic esters have been prepared via the regioselective cycloaddition of 2-pyrones with alkynylboronates.

The Diels–Alder cycloaddition is arguably the most powerful reaction for the construction of substituted six-membered rings from various 2p and 4p reactants. However, unactivated 2p and 4p systems either require very harsh conditions or fail to undergo cycloadditions. In many cases, transition metal catalysts facilitated chemical transformations that were inaccessible under thermal conditions a...

Phosphine-catalyzed [3+2]cycloaddition reactions of electron-deficient allenes and alkynes with a,b-unsaturated carbonyl compounds can give access to important highly functionalized cyclopentenes. The seminal example of such a transformation was first reported by Lu et al. in 1995, and its asymmetric version in 1997 by the group of Zhang. However, it took another ten years before the potential ...

The [4+2] cycloaddition of 3-alkoxyfurans with N-substituted maleimides provides the first general route for preparing endo-cantharimides. Unlike the corresponding reaction with 3H furans, the reaction can tolerate a broad range of 2-substitued furans including alkyl, aromatic, and heteroaromatic groups. The cycloaddition products were converted into a range of cantharimide products with promis...

A triple cascade was developed using a simple copper catalyst to trans-selectively access bicyclic isoxazolidines in a one-pot synthesis. This strategy features the in situ generation of nitrones and subsequent trapping by [3 + 2] cycloaddition. In this method, copper serves three catalytic functions: as a Lewis acid for the ene reaction, as an organometallic for aerobic oxidation, and as a Lew...

The synthesis and antibacterial activity of the title compounds having an isoxazolidine ring at the C-2 position are described. These derivatives were synthesized by the 1,3-dipolar cycloaddition reaction of nitrone with 2-vinyl carbapenems. This 1,3-dipolar cycloaddition reaction proceeded regioselectively to give diastereomeric isomers of 2(-isoxazolidin-5-yl)carbapenems. It was ascertained t...