tert-Butyl (Mesitylsulfonyl)oxycarbaMate

Tert-Butyl (Mesitylsulfonyl)oxycarbaMate is a useful reagent for the enantioselective aziridination of α,β-unsaturated aldehydes.

2-Mesitylenesufonylchloride (2.00 g, 9.17 mmol) was added to a flame dried and argon purged round-bottom flask and dissolved in ether (18 mL), followed by the addition of N-Boc-hydroxylamine (1.47 g, 1100 mmol) The flask was cooled to 0° C and then TEA was added dropwise (1.3 mL). The reaction stirred for 2 hours at 0° C, at which all starting material had been converted as seen by TLC. The TEA-Cl, white solid, was filtered, and washed with ether. The filtrate was concentrated in vacuo, and purified via flash chromatography in 25/75 EtOAc/hexane gradient. Yield was quantitative, 2.16 g, white solid.

Separation of 1,1-Dimethylethyl (((2,4,6-trimethylphenyl)sulphonyl)oxy)carbamate on Newcrom R1 HPLC column:1,1-Dimethylethyl (((2,4,6-trimethylphenyl)sulphonyl)oxy)carbamate can be analyzed by this reverse phase (RP) HPLC method with simple conditions. The mobile phase contains an acetonitrile (MeCN), water, and phosphoric acid. For Mass-Spec (MS) compatible applications the phosphoric acid needs to be replaced with formic acid. Smaller 3 μm particles columns available for fast UPLC applications. This liquid chromatography method is scalable and can be used for isolation impurities in preparative separation. It also suitable for pharmacokinetics.