Sodium borohydride → tert-butyl ((1S,4S)-4-(2-hydroxyethyl)-4-(hydroxymethyl)cyclopent-2-en-1-yl)carbamate

Participants

Reaction Steps

To a solution of the product of Step E (255.9 g, 1.01 mol) and MeOH (2 L) chilled to 2° C. was added NaBH4 (75 g) over ˜2.5 h. The reaction was quenched by addition of aqueous NH4Cl, concentrated under reduced pressure and the mixture was diluted with water and EtOAc. The layers were separated and the aqueous layer was extracted with additional EtOAc. The combined organics were washed with brine, dried (MgSO4) and evaporated to give the product of Step F as a thick oil. 1H NMR (400 MHz, CHLOROFORM-d) d=5.74 (d, J=2.0 Hz, 2H), 4.81-4.92 (m, 1H), 4.67-4.79 (m, 1H), 3.71 (t, J=6.1 Hz, 2H), 3.50 (d, J=11.7 Hz, 2H), 2.14-2.28 (m, 2H), 1.70 (td, J=1.6, 6.2 Hz, 4H), 1.52-1.60 (m, 1H), 1.44 (s, 9H)

Provenance & Evidence