Novel Methoxymethyl 3‐Bromoboldine Derivatives with Improved Capabilities as Precursors for Organic Synthesis

Abstract

Ortho‐directed metalation of boldine (1) is a possible route to new compounds with pharmacological potential. Three new methoxymethyl (MOM) derivatives of 3‐bromoboldine were prepared and fully characterized: 2‐O‐methoxymethyl‐3‐bromoboldine (5), 9‐O‐methoxymethyl‐3‐bromoboldine (6), and 2,9‐O,O′‐dimethoxymethyl‐3‐bromoboldine (7). Compound (7) proved to be superior in yield and selectivity to 2,9‐ O,O′‐dimethoxymethylboldine (3) as a reaction precursor for the preparation of novel 3‐substituted boldine derivatives.

Keywords:

• boldine
• methoxymethyl derivatives
• ortho‐directed metalation
• synthesis

Acknowledgments

The authors are grateful to the Universidad Técnica Federico Santa María (Proy. D.G.I.P. 13.04.24) for financial support. We thank Bruce K. Cassels (Universidad de Chile) for reading the manuscript and for his helpful comments.