Lithium Chloride → (2S,4S)-2-hydroxymethyl-N-(p-nitrobenzyloxycarbonyl)-4-tritylthiopyrrolidine

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Reaction Steps

To a solution of (2S,4S)-4-triphenylmethylthio-2-methoxycarbonyl-1-p-nitrobenzyloxycarbonylpyrrolidine (3: 3.63 g) in tetrahydrofuran (36 ml) under ice cooling are added a solution of sodium borohydride (371 mg) in ethanol (15 ml) and a solution of lithium chloride (554 mg) in tetra-hydrofuran (15 ml), and the mixture is warmed to room temperature and stirred for 110 minutes. The reaction mixture is diluted with ethyl acetate under ice cooling, neutralized with 1N-hydrochloric acid (10 ml) to decompose remaining reagent. The organic layer is taken, washed with water and saturated brine, dried over sodium sulfate, and concentrated in vacuo. The residue is purified by silica gel chromatography to give (2S,4S)-4-triphenylmethylthio-2-hydroxymethyl-1-p-nitrobenzyloxycarbonylpyrrolidine (4: 3.02 g) as colorless foam. Yield: 88%. IR ν (CHCl3) cm-1 : 3400, 1679, 1603. 1HNMR δ (CDCl3) ppm: 1.3 to 2.13(2H, m), 1.6(1H, brs), 2.65 to 4.3(6H, m), 5.03 to 5.2(2H, m), 7.07 to 7.55(17H, m), 8.15 to 8.3(2H, m).

Provenance & Evidence