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The mechanisms involved in the catalytic enantio- and stereoselective radical cyclization process facilitated by a regiodivergent epoxide opening are discussed. The significance of the catalysts in controlling the process is also demonstrated.

A system for coupling catalytic radical cyclization and Ir-catalyzed hydrogen atom transfer (HAT) is described. It is essential that the HAT catalyst activates H2 quickly and is not a hydrogenation catalyst. Vaska's complex was found to fulfill both purposes efficiently. [ABSTRACT FROM AUTHOR]

A catalytic enantio- and diastereoselective radical cyclization using a regiodivergent epoxide opening (REO) for radical generation is described. It is demonstrated for the first time that the diastereoselectivity of cyclizations of acyclic radicals can be controlled catalytically. Building blocks for important applications in stereoselective synthesis are readily accessed. [ABSTRACT FROM AUTHOR]

A system of three coupled catalytic cycles enabling the one-pot transformation of epoxides to amines via Meinwald rearrangement, imine condensation, and imine reduction is described. This assisted tandem catalysis is catalyzed by B(C6F5)3 resulting in the first tandem Meinwald rearrangement-reductive amination protocol. The reaction proceeds in nondried solvents and yields β-functionalized amines. In particular, β-diarylamines are obtained in high yields.

The first shape-persistent macrocycle 1 offering a Brønsted pair functionalized interior is described. Via postcyclization transformation, this heterosequenced compound can be obtained from its corresponding ester 2. The macrocycles differ dramatically in their characteristics such as solubility and appearance. Theoretical investigations suggest that those contrasts might originate from conformational changes due to the formation of a strong O-H-N hydrogen bond in 1.