p-Toluenesulfonic acid monohydrate → (R)-tert-Butyl (1-hydroxybut-3-yn-2-yl)carbamate

Participants

Reaction Steps

A solution of (R)-N-Boc-2,2-dimethyl-4-ethynyl-oxazolidine (200 mg, 0.89 mmol) (Example 91A above) in a mixture of MeOH (10 mL) and water (1 mL) was treated with p-toluenesulfonic acid monohydrate (16 mg, 0.09 mmol). After stirring at reflux overnight a thermodynamic mixture of starting material and product was obtained (appr. 1:1). The solvent was concentrated and the product was separated from the starting material via silica gel column chromatography with a 0-60-100% EtOAc in hexanes gradient. The recovered starting material was subjected to the above process for two more times yielding (R)-N-Boc-2-amino-but-3-yn-1-ol. (Yield 150 mg, 91%).

Provenance & Evidence