Carbonic acid, bis(1,1-dimethylethyl) ester → Ethyl-2-allyl-2-(tert-butoxycarbonylamino)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)hexanoate

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Reaction Steps

A solution of ethyl 2-allyl-2-amino-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)hexanoate (0.0897 g, 0.276 mmol) in ethyl acetate (0.6 mL, 0.5 M) and saturated aqueous NaHCO3 (0.6 mL) was treated with di-tert-butyl carbonate (0.090 g, 0.414 mmol) and stirred at room temperature. After 16 h, the layers were separated and the aqueous layer was extracted with ethyl acetate. The combined organic layers were washed with saturated aqueous NaCl, dried over MgSO4, filtered and concentrated. Purification by MPLC (0-20% ethyl acetate in heptane over 6 CV) gave ethyl 2-allyl-2-(tert-butoxycarbonylamino)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)hexanoate as a colorless oil (0.096 g, 82%). Rf 0.53 (30% ethyl acetate in heptane); ESI-LCMS m/z calcd for C22H40BNO6: 425.3. found 426.3 (M+H)+.

Provenance & Evidence