1.1: diisopropylamine; n-BuLi / tetrahydrofuran; petroleum ether / 1 h / -78 °C 1.2: tetrahydrofuran; petroleum ether / 12 h / 22 °C 2.1: 93 mg / aq. AcOH / CH2Cl2 / 0.75 h / 22 °C View Scheme

in not given

sodium ethanolate

1: 1-(tetrahydropyran-2-yloxy)-4-pentyne With n-butyllithium in tetrahydrofuran; hexane T=-78°C; 2 h; 2: dimethyl (iodomethyl)-phenylsilane in tetrahydrofuran; hexane 16 h; Heating; Further stages.;