copper(l) iodide; methyllithium in diethyl ether T=-40 - 0°C; 3 h; Inert atmosphere; regioselective reaction;

1.1: titanium (IV) isopropoxide; D-(-)-diisopropyl tartrate / dichloromethane / 0.5 h / -24 °C / |Inert atmosphere; |Molecular sieve 1.2: 24 h / -24 °C / |Inert atmosphere; |Molecular sieve 2.1: copper(l) iodide; methyllithium / diethyl ether / 3 h / -40 - 0 °C / |Inert atmosphere View Scheme

Multistep reaction. Title compound not separated from byproducts;

Multistep reaction. Title compound not separated from byproducts;