Sodium borohydride → HCID 68807529, compound

Participants

Reaction Steps

To a solution of 15 (1 eq) dissolved in absolute ethanol (7 mL/g of 15) was added solid sodium borohydride slowly over 10 minutes. This mixture was allowed to stir at room temperature for 24 hours after which time the ethanol was removed under aspirator vacuum and the residue carefully dissolved in 0.5N HCl (6 mL/g of 15). This solution was washed twice with ether (3 mL/g of 15 for each wash) and then the aqueous solution is made basic with 50% NaOH solution (pH=14) and the ether layers discarded. This solution was then saturated with sodium chloride and extracted five times with 3:1, methylene chloride:THF, (3 mL/g of 15 for each extraction) and the combined organic layers were dried over magnesium sulfate and the solvent removed under aspirator vacuum to provide 16 as a yellow oil in 95% yield from 15 as a mixture of 7-hydroxy diastereomers. This material is used in the next step without purification. 1H NMR (CDCl3): δ0.46-0.48(d, J=6.90 Hz, 3H), 1.32-1.34 (d, J=6.02 Hz, 6H), 1.47-1.58(m, 2H), 1.87-1.93(dd, J=14.16, 5.09 Hz, 2H), 2.27-2.47 (m, 8H), 2.69-2.75 (dd, J=11.64, 5.26 Hz, 1H), 3.09 (br s, 1H), 4.02-4.05 (t, J=4.83 Hz, 1H), 4.47-4.59 (septet, J=6.07 Hz, 1H)5.30 (br s, 1H), 6.68-6.81 (m, 3H), 7.7.16-7.62 (in, 1H).

Provenance & Evidence