摘要 |
<p>A process for preparing 8-substituted oxy-5-((R)-2-halo-1-hydroxy-ethyl)-(1H)-quinolin-2-ones or acceptable solvates thereof. The process involves reacting a 5-(alpha-haloacetyl)-8-substituted oxy-(1H)-quinolin-2-one with a reducing agent in the presence of a chiral agent and a base to form a 8-(substituted oxy)-5-((R)-2-halo-1-hydroxy-ethyl)-(1H)-quinolin-2-one, said chiral agent having a formula I or II wherein M, L, X, R1, R2 and R3 have the meanings as indicated in the specification.</p> |