The invention provides a preparing method of (S)-3-hydroxy
tetrahydrofuran, which comprises the following steps: (1) adding (S)-4-Cl-3-hydroxy
ethyl butyrate,
potassium carbonate,
benzyl chloride and DMF into a tri-opening
bottle, stirring, refluxing, reducing pressure, standing,
drying after washing, and recrystallizing; (2) adding
tetrahydrofuran and
sodium borohydride into a
tetra-opening
bottle; stirring and dropwise adding (S)-4-Cl-3-benzyloxy
ethyl butyrate, continuing to stir, performing rotary
evaporation condensing, cooling, neutralizing after stirring, extracting, and rectifying after rotary
evaporation condensing; (3) adding (S)-4-Cl-3-benzyloxy-1-
butanol, water and concentrated
hydrochloric acid into a tri-opening
bottle, starting stirring, heating, then performing temperature preserving reaction, neutralizing, extracting, and distilling after rotary
evaporation condensing; (4) dissolving (S)-3-benzyloxy
tetrahydrofuran in tetrahydrofuran, adding
palladium carbon, introducing
hydrogen, stirring to react, filtering, concentrating under reduced pressure, adding the recrystallized product, filtering after icy bath cooling, and
drying to obtain the (S)-3-hydroxy tetrahydrofuran. The
intermediate product is easy to separate and the yield is higher.