Reaction #2200585

Reaction equation

water

(2R,3S)-2-methyl-3-benzyloxybutanol

Et3N

ether

→

(2S,3S)-2-methyl-3-benzyloxybutyraldehyde

Solvents

DMSO

Conditions

Workup

1. 1
   workup.WAITat room temperature for 2 hours
2. 2
   ExtractionThe aqueous layer was extracted with ether
3. 3
   WashThe combined ether extracts were washed with 1M HCl, waters saturated NaHCO3, brine, and they
4. 4
   Dryingwere dried over Na2SO4
5. 5
   Otherevaporated in order

Procedure

The Py.SO3 complex (4.09 g, 25.67 mmol, 6.0 eq.) was added in portions at 0° C. to a solution of (2R,3S)-2-methyl-3-benzyloxybutanol (13) (830 mg, 4.28 mmol) and Et3N (2.86 g, 3.93 ml, 28.25 mmol, 6.6 eq.) in DMSO (14 ml). The reaction mixture is stirred at 0° C. for 3.5 hours, and then at room temperature for 2 hours, and then it was divided between water and ether. The aqueous layer was extracted with ether. The combined ether extracts were washed with 1M HCl, waters saturated NaHCO3, brine, and they were dried over Na2SO4 and evaporated in order to obtain crude (2S,3S)-2-methyl-3-benzyloxybutyraldehyde which was used directly for the next reaction without purification. 1H NMR (250 MHz, CDCl3) δ 9.73 (d, J=2.4 Hz, 1H); 4.63 (d, J=11.7 Hz, 1H); 4.44 (d, J=11.7 Hz, 1H); 3.81 (quintuplet, J=6.4 Hz, 1H); 2.57 (quintuplet-d, J=7.0; 2.4 Hz, 1H); 1.25 (d, J=6.2 Hz, 3H); 1.09 (d, J=7.1 Hz, 3H).

Source