1,3-Dipolar Cycloadditions to Bicyclic Olefins. I. 1,3-Dipolar Cycloadditions to Norbornadienes

Enantioselective 1,3-dipolar cycloadditions of diazoacetates with electron-deficient olefins.

[reaction: see text] A general strategy for highly enantioselective 1,3-dipolar cycloaddition of diazoesters to beta-substituted, alpha-substituted, and alpha,beta-disubstituted alpha,beta-unsaturated pyrazolidinone imides is described. Cycloadditions utilizing less reactive alpha,beta-disubstituted dipolarophiles require elevated reaction temperatures, but still provide the corresponding pyraz...

Iridium–catalyzed 1,3–dipolar cycloadditions

1,3–Dipolar cycloaddition reactions (DCR) are atom–economic processes that permit the construction of heterocycles. Their enantioselective versions allow for the creation of up to four adjacent chiral centers in a concerted fashion. In particular, well–defined half–sandwich iridium (III) catalysts have been applied to the DCR between enals or methacrylonitrile with nitrones. Excellent yield and...

Enantioselective copper-catalyzed 1,3-dipolar cycloadditions.

1,3-Dipolar cycloadditions: applications to the synthesis of antiviral agents.

In the present perspective the advances and real possibilities of 1,3-dipolar cycloadditions as key steps in the total synthesis of virus inhibitors are described. Azides, nitrones, and azomethine ylides are the most appropriate 1,3-dipoles for the synthesis of privileged structures with the highest biological responses against viruses.

Access to functionalised silver(I) and gold(I) N-heterocyclic carbenes by [2 + 3] dipolar cycloadditions.

A new strategy was developed for the modification of silver(I) and gold(I) N-heterocyclic carbenes. Azido groups were grafted and used either by copper-catalysed azide-alkyne cycloaddition before metallation or by thermal and "strain-promoted" 1,3-dipolar cycloaddition after metallation to functionalise the metal-NHCs.