Carbamic acid 2,6-di-sec-butylphenyl ester → (r,r,r)-1-Phenylethylcarbamic acid-2,6-di-sec-butylphenyl ester

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Reaction Steps

To an Agilent HPLC system fitted with a diode array detector and a 0.46 cm ID×25 cm long 10 mm KROMASIL Silica Column was charged 714 mg of racemic R-(+)-1-phenyl-ethyl)-carbamic acid-2,6-di-sec-butylphenyl ester dissolved in 10 ml of hexane/ethyl acetate (98:2) to give a 71.4 g/l feed solution. The sample was eluted with hexane/ethyl acetate (98:2) at 2 ml/min at 25° C. Fractions containing (R,R,R)-1-phenylethylcarbamic acid-2,6-di-sec-butylphenyl ester were collected and evaporated under reduced pressure at <55° C. At the highest loading, the (R,R,R)-stereoisomer was collected with a chiral purity of 98.7% diastereomeric excess (de) and a total yield of 53%.

Provenance & Evidence