反应 #1702176

ord-f320e0728bc8497ab9a6ddbc698743d9

反应方程式

C1CCOC1
tetrahydrofuran
BrC1=NOCC1
racemic 3-bromo 4,5-dihydroisoxazole
COC(=O)c1cncc(O)c1
5-hydroxynicotinic acid methyl ester
[Li+].[OH-]
lithium hydroxide
c1cncc(OC2=NOCC2)c1
3-(pyridin-3-yloxy)-4,5-dihydroisoxazole

反应条件

详细条件
See reaction.notes.procedure_details.

后处理

  1. 1
    workup.ADDITIONwas added
  2. 2
    其他was removed under a stream of nitrogen

实验过程

The enantiomers of 3-(pyridin-3-yloxy)-4,5-dihydroisoxazole III-74a and III-74b were prepared in 2 steps according to the following procedures: racemic 3-bromo 4,5-dihydroisoxazole III-66 was reacted with 5-hydroxynicotinic acid methyl ester using Method 5. The resulting ester (1.0 equiv) was dissolved in 1:1 tetrahydrofuran/water (0.06 M) and lithium hydroxide (8.0 equiv) was added. The reaction was allowed to stir at room temperature for 1 h after which point the tetrahydrofuran was removed under a stream of nitrogen and the remaining solution was acidified to pH<2 with 1N HCl to provide the racemic desired acid III-74 as a white solid which was isolated via vacuum filtration. These compounds can be separated using chiral HPLC methods known in the art. For example, see chiral HPLC Method disclosed herein. [M+H]+=395.5 m/z. Activity: A

来源

DOI: 10.6084/m9.figshare.5104873.v1专利: US08765735B2uspto-grants-2014_07