Easily accessible non-aromatic heterocycles with handles: 4-bromo-2,3-dihydrofurans from 1,2-dibromohomoallylic
Jason An1, Jose Intano1, Alissa Richard1
1Department of Chemistry, University of Connecticut Storrs CT 06269 USA amy.howell@uconn.edu jose.gascon@uconn.edu.
Abstract:
The first general preparation of 4-bromo-2,3-dihydrofurans is reported. These non-aromatic heterocycles containing a useful coupling handle are accessed via Cu-catalyzed intramolecular cyclization of 1,2-dibromohomoallylic alcohols, which are themselves available in just two steps from aromatic and aliphatic aldehydes and ketones. Molecular dynamics simulations using the simple substrates and key geometric parameters provide a rationale for the selectivities observed. The synthetic utility of the 4-bromodihydrofurans is also demonstrated.
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