A convenient formation of aporphine core via benzyne chemistry: conformational analysis and synthesis of (R)-aporphine

Total synthesis of (R)-aporphine has been accomplished by an approach that employs in the key step a sequence of transformations involving a [4+2] cycloaddition reaction followed by a hydrogen migration, leading to aporphine core in good yield, which was subjected to a 1D gradient NOE experiment, conformational analysis, and simple transformations, including a small scale resolution process, to afford enantiomericallyenriched aporphine alkaloid. (C) 2015 Elsevier Ltd. All rights reserved.