From Cycloalkanols to Heterocycles via Nitrogen Insertion
Alexander Sandvoß1, Johannes M Wahl1
1Department Chemie, Johannes Gutenberg-Universität, Duesbergweg 10-14, 55128 Mainz, Germany.
Abstract:
A variety of cyclic alcohols are found to undergo nitrogen insertion by subjection to O-mesitylsulfonylhydroxylamine. Critical to a successful process is the use of fluorinated alcoholic solvents, which ensures sufficient substrate activation to allow engagement with the ambiphilic aminating agent. This transition-metal-free nitrogen insertion provides access to a variety of medicinally relevant heterocycles such as pyrrolidenes, quinolines, and benzazepines (24 examples). Furthermore, combination with a photochemical Norrish-Yang-type cyclization allows an unprecedented access to indoles from ortho-substituted acetophenones.
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