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Updated: May 10, 2026

Chemoselective Preparation of 1-Iodoalkynes, 1,2-Diiodoalkenes, and 1,1,2-Triiodoalkenes Based on the Oxidative Iodination of Terminal Alkynes
Published on: September 12, 2018
Enantioselective synthesis of (R)-tolterodine using lithiation/borylation-protodeboronation methodology
Stefan Roesner1, Varinder K Aggarwal
1School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
Abstract:
The synthesis of the pharmaceutical (R)-tolterodine is reported using lithiation/borylation-protodeboronation of a homoallyl carbamate as the key step. This step was tested with two permutations: an electron-neutral aryl Li-carbamate reacting with an electron-rich boronic ester and an electron-rich aryl Li-carbamate reacting with an electron-neutral boronic ester. It was found that the latter arrangement was considerably better than the former. Further improvements were achieved using magnesium bromide in methanol leading to a process that gave high yield and high enantioselectivity in the lithiation/borylation reaction. The key step was used in an efficient synthesis of (R)-tolterodine in a total of eight steps in a 30% overall yield and 90% ee.
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