Staudinger cycloaddition

The Staudinger [2+2] cycloaddition of chiral carbohydrate Schiff base with phthalimidoacetyl chloride has yielded the sugar-based monocyclic (3-lactam as a single isomer [88]. This latter could be transformed in several (3-lactams variously functionalized through ozonolysis, reduction, hydrolysis, and acetylation reactions, (Scheme 26). 

Scheme 26 Synthesis of sugar-based monocyclic [S-lactams by Staudinger [2+2] cycloaddition reaction...

Reaction of D-phenylalanine ethyl ester with cinnamaldehyde has been reported to give a chiral Schiff base, that underwent an asymmetric Staudinger [2+2] cycloaddition reaction with phthalimidoacetyl chloride to give the monocyclic... 

A combined theoretical and experimental study has been reported for the formation of silylated (3-lactams, via Staudinger [2+2] cycloaddition reaction from silylketenes and imines, in the presence or in the absence of a Lewis acid... 

A procedure based on Ru-catalyzed metathesis sequences with oxanorbomene precursors (I, Fig. 20), obtained by the Staudinger [2+2] cycloaddition of related imines, has been reported to lead to spiro-(3-lactams tethered to tetrahydrofuran rings (II, Fig. 20), [292],... 

Ketenes are another type of unsaturated molecules of high electron deficiency and structural strains therefore, they are very reactive for the [2+2] cycloaddition. The most common [2+2] cycloaddition involving ketenes are Staudinger [2+2] Cycloadditions to form fi-lactones, initially reported in 1911, and the dimerization of ketenes." Besides the easy cycloaddition with imine, as shown in the Staudinger [2+2] Cycloaddition, ketenes can also react with aldehydes to afford /3-lactones. It has been found that high diastereoselectivity can... 

This reaction is related to the Diels-Alder Reaction, de Mayo Reaction, Patemo-BUchi Reaction, and Staudinger [2+2] Cycloaddition. 

More recently, Williams and co-workers employed a Staudinger [2+2] cycloaddition of the highly oxygenated benzaldimine 17 to Evans-Sjogren ketene 16 during the... 

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