Rh -catalyzed synthesis

Several new syntheses of oxazolidinones as well as the application of these procedures for the synthesis of natural products were published. The Rh-catalyzed synthesis of... 

Nakaura and Ukita devised a simple indole synthesis from the Rh-catalyzed condensation of a-diazophospho-nates and o-acylanilines (Scheme 6, equation 1) [58]. Moody and colleagues combined diethyl diazomalonate and Af-alkylanilines in a Rh-catalyzed synthesis of indox-ylic acid esters (equation 2) [59], This chemistry represents a simple synthesis of these rare indoxyl-2-carboxylates. 

Scheme 63 Rh-catalyzed synthesis of isoquinoline and pyridine W-oxides.

Scheme 2.8 Rh-catalyzed synthesis of pyridines from a-alkynyl-vinyl oximes.

A Rh-catalyzed synthesis of pyridines from aldehydes, alkynes, and NH4OAC via hydroacylation and A-annulation was reported by Jun and CO workers in 2012 [90]. More in detail, the reaction consisted of Rh(I)-catalyzed chelation-assisted hydroacylation of alkynes with aldehydes followed by Rh(III)-promoted A-annulation of the resulting a,(3-enones with another alkyne and NH3. Moderate to good yields of the desired pyridines were produced (Scheme 3.42). 

Scheme 3.43 Rh-catalyzed synthesis ofpyridines from alkynes.

Scheme 3.50 Rh-catalyzed synthesis of pyrid sfrom a -unsaturated N-bmzyl eddimmes and ketimines.

SCHEME 14 Rh-catalyzed synthesis of the natural furo[3,2-c]coumarin pterophyUin 2. 

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