<b>Multi-step reaction with 5 steps<br /> </b>1.1: triethylamine / N,N-dimethyl-formamide / 20 - 50 &deg;C<br />1.2: 6 h / 100 &deg;C<br />2.1: trichlorophosphate / 0.67 h / cooling with ice<br />2.2: 3 h / 20 &deg;C<br />2.3: 0.5 h<br />3.1: ammonium acetate / 1 h / Reflux<br />4.1: ethanol; sodium tetrahydroborate / tetrahydrofuran / 1.5 h / 20 &deg;C / cooling with ice<br />4.2: 1 h / pH 4<br />5.1: trichlorophosphate / 0.83 h / cooling with ice<br />5.2: 2.58 h / 50 &deg;C<br /> <br /> &nbsp;