The strategic use of a sequential Sonogashira coupling/intramolecular alkyne-carbonyl metathesis process for the synthesis of a pyridine ring from 1-(2-haloaryl)-1H-pyrrole-2-carbaldehydes allowed ready access to diverse novel benzo-fused indolizines, pyrrolo[1,2-a]quinolines, in good to excellent yields. As a hybrid structure of indolizine and quinoline, the resulting scaffold has an acyl substituent at the C5 position, which is difficult to make by any other known approaches.

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A new approach for the synthesis of novel annulated-pyrazoles is presented. This protocol includes an intermolecular condensation followed by a copper-mediated intramolecular C À N or C À O coupling reaction. The method is applied to a range of substituted 4-iodopyrazolecarbaldehydes which react with 1,2-phenylenediamines or 2-

An efficient copper‐catalyzed cascade reaction of 4‐iodopyrazolecarbaldehydes and 4‐iodopyrazolecarboxamides with substituted amidines for the preparation of substituted pyrazolo[4,3‐d]pyrimidines and pyrazolo[4,3‐d]pyrimidin‐7(6H)‐ones, respectively, is described.

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An unprecedented copper-catalyzed intramolecular amidation of substituted 4-iodopyrazoles generated either via Baylis-Hillman or Horner-Wadsworth-Emmons chemistry for the synthesis of pyrazoloA C H T U N G T R E N N U N G [4,3-b]pyridine-5-ones is described. In addition, the effect of the stereochemistry of the acrylamide on the cross-coupling reaction has been investigated and it is demonstrated that only the Z-isomer is favoured to undergo the intramolecular cyclization.

A highly convergent synthetic approach to rotenoid natural products is described. Successful pairing of two building blocks for Sonogashira cross-coupling and intramolecular alkyne carbonyl metathesis allows ready access to 4-acylchromene, a key substructure of these natural products, leading to syntheses of (±)-deguelin and (±)-munduserone in high overall yields.