Asymmetric Synthesis of (S)-(-)-Xylopinine. Use of the Sulfinyl Group as an Ipso Director in Aromatic S-E

作者：Mastranzo Virginia M; Yuste Francisco^*; Ortiz Benjamin; Sanchez Obregon Ruben; Toscano Ruben A; Garcia Ruano Jose L

来源：Journal of Organic Chemistry, 2011, 76(12): 5036-5041.

DOI：10.1021/jo2007237

Optically pure (S)-(-)-xylopinine 2 was prepared in three steps in 52% overall yield. Thus, condensation of the carbanion derived from (S)-4 with the (S)-(E)-sulfinylimine 5 gave a 2:1 mixture of tetrahydroisoquinolines 6a and 6b, differing only in configuration at sulfur. N-Desulfinylation of this mixture gave the diastereomeric sulfoxides which, without separation, were converted into (S)-(-)-xylopinine (2) with loss of the sulfinyl moieties under Pictet-Spengler conditions. This unprecedented ipso electrophilic substitution of a sulfinyl group may have synthetic implications beyond that described in this work.

• 出版日期2011-6-17