1: n-butyl-triphenylphosphonium bromide With potassium tert-butylate in tetrahydrofuran Inert atmosphere; 2: acetic acid 8-oxo-octyl ester in tetrahydrofuran T=-15 - 20°C; Inert atmosphere;

1.1: potassium tert-butylate / tetrahydrofuran / Inert atmosphere 1.2: -15 - 20 °C / Inert atmosphere 2.1: nitric acid; sodium nitrite / water / 1 h / 70 - 75 °C / Inert atmosphere View Scheme

1: n-butyl-triphenylphosphonium bromide With potassium tert-butylate in tetrahydrofuran Inert atmosphere; 2: acetic acid 8-oxo-octyl ester in tetrahydrofuran T=-15 - 20°C; Inert atmosphere;

1.1: potassium tert-butylate / tetrahydrofuran / Inert atmosphere 1.2: -15 - 20 °C / Inert atmosphere 2.1: nitric acid; sodium nitrite / water / 1 h / 70 - 75 °C / Inert atmosphere View Scheme

1: With piperidine; pyridine T=22 - 120°C; Doebner reaction; 24.5 h; 2: With potassium carbonate in methanol T=20°C; 24 h;

1: 69 percent / KF, Ac2O, NaBH4 2: 97 percent / NaOH View Scheme

<b>Multi-step reaction with 2 steps<br /> </b>1: (i) AgOAc, (ii) SOCl₂, benzene<br />2: H₂ / Pd-BaSO₄ / xylene / 150 - 160 &deg;C<br /> <br /> &nbsp;

<b>Multi-step reaction with 4 steps<br /> </b>1.1: 93 percent / pyridine / 24 h / 20 &deg;C<br />2.1: 78 percent / Br₂; HgO / CCl₄ / 4 h / Irradiation<br />3.1: 81 percent / LiBr; Li₂CO₃ / dimethylformamide / 6 h / 120 &deg;C<br />4.1: ozone / CH₂Cl₂ / cooling<br />4.2: 71 percent / zinc; acetic acid / CH₂Cl₂; H₂O<br /> <br /> &nbsp;

<b>Multi-step reaction with 2 steps<br /> </b>1.1: 81 percent / LiBr; Li₂CO₃ / dimethylformamide / 6 h / 120 &deg;C<br />2.1: ozone / CH₂Cl₂ / cooling<br />2.2: 71 percent / zinc; acetic acid / CH₂Cl₂; H₂O<br /> <br /> &nbsp;

<b>Multi-step reaction with 3 steps<br /> </b>1.1: 78 percent / Br₂; HgO / CCl₄ / 4 h / Irradiation<br />2.1: 81 percent / LiBr; Li₂CO₃ / dimethylformamide / 6 h / 120 &deg;C<br />3.1: ozone / CH₂Cl₂ / cooling<br />3.2: 71 percent / zinc; acetic acid / CH₂Cl₂; H₂O<br /> <br /> &nbsp;