Selected Applications and Extensions of Azomethine Cycloadditions

This cycloaddition takes place to give the exo cycloadduct, rather than the more common endo cycloadduct, as the major product. Presumably this is a consequence of the intermediate munchnone 131 being locked in an anti orientation as compared to the commonly favored syn orientation (as in 24). 

2- naphthylmethyliminoglycyl ester 103 to give the product in only 42% yield and 2 1 endo exo diastereoselectivity. Low diastereoselectivity also resulted from the cycloaddition of these nitroolefins with homoserine-lactone-derived imines.61 

The incorporation of fluorine is one of the most commonly employed strategies in lead optimization in medicinal chemistry. Franchini has reported that trans methyl 

R3 = 9-anthracyl, 3-indolyl, 4-HO-3-MeOC6H3, 2-furyl, 2-thienyl, 3-pyridyl 

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