<b>Multi-step reaction with 4 steps<br /> </b>1.1: water / 5 h / 80 &deg;C / |Cooling with ice; |Sealed tube<br />2.1: triphenylphosphine; diethylazodicarboxylate / dichloromethane / 6 h / 20 &deg;C / |Cooling with ice<br />3.1: ammonium chloride / water / 5 h / 110 &deg;C / |Sealed tube<br />4.1: L-(+)-tartaric acid / ethanol / 1 h / 20 &deg;C / |Reflux; |Resolution of racemate<br />4.2: 20 &deg;C / pH 9-10 / |Reflux; |Resolution of racemate<br /> <br /> &nbsp;