Rhodium oxygen containing heterocycles

The transition-metal-catalyzed reaction of diazo compounds 702, which have a N—H or O—H bond at an appropriate position, gives nitrogen- and oxygen-containing heterocycles 703 (Scheme 2 1 8).293 Wang and Zhu demonstrated a convenient synthesis of the polyfunctionalized /Tfluoropyrroles by the rhodium-catalyzed intramolecular N—H insertion reaction.2933 The reaction of d-amino-y,y-difluoro-a-diazo-/Tketo esters 704 in the presence of Rh2(OAc)4 gave the... 

Elgafi S, Field LD, Messerle BA (2000) Cyclization of acetylenic carboxylic acids and acetylenic alcohols to oxygen-containing heterocycles using cationic rhodium(I) complexes. J Organomet Chem 607 97-104... 

Abstract Carbon d ylide dipoles are important intermediates with great application in heterocyclic chemistry. Here, we show how the rhodium-catalyzed a-diazocarbonyl compounds are employed in the generation of carbonyl ylides and their effective use for the synthesis, as well as functionalization, of heterocycles. Herein we discuss recent advancements in this field mainly describing the synthesis and importance of various oxygen-and nitrogen-containing heterocyclic systems and natural products from a-diazocarbonyl compounds. 

Herein rhodium-catalyzed inter- and intramolecular cycloadditions of carbonyl ylides derived from a range of diazocarbonyl compounds leading to oxygen- and nitrogen-containing heterocyclic systems and natural products are discussed. We have focussed on the last five years for the most significant developments of the reactions of carbonyl ylides derived from diazocarbonyl compounds. 

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