Methanol → 1-[5-(5-Chloro-thiophen-2-yl)-isoxazol-3-ylmethyl]-5-hydroxymethyl-1H-pyrazole-3-carboxylic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

To a solution of 4 g 1-[5-(5-Chloro-thiophen-2-yl)-isoxazol-3-ylmethyl]-1H-pyrazole-3,5-dicarboxylic acid 3-ethyl ester in 50 ml THF 26 ml BH3*THF (1M in THF) were added slowly at RT. Then the mixture was warmed to 40° C. for 6h. After cooling to 0° C. 20 ml MeOH were added cautiously and the mixture was concentrated to dryness. The residue was again codistilled with 20 ml of MeOH and then purified by chromatography on silica gel eluting with n-heptane/ethyl acetate. The fractions containing the product were combined and the solvent evaporated under reduced pressure. Yield: 1.9 g.

Provenance & Evidence