反応 #474388

反応方程式

(2S,4R)-1-(tert-butoxycarbonyl)-4-hydroxypyrrolidine-2-carboxylic acid

TEMPO

KHSO4

→

title compound

(S)-1-(tert-butoxycarbonyl)-4-oxopyrrolidine-2-carboxylic acid

溶媒

isopropyl acetate

反応条件

後処理

1. 1
   workup.ADDITIONA solution of bleach (12.5 wt %, 1.2 eq., 2.6 vol) was then slowly added over 1 hour
2. 2
   workup.STIRRINGstirred for 10 minutes
3. 3
   その他the phases were separated
4. 4
   洗浄The organic phase was washed with aqueous 5% Na2SO3 (2 vol)
5. 5
   乾燥brine (1 vol) then dried azeotropically
6. 6
   濃縮concentrated

実験手順

A solution of (2S,4R)-1-(tert-butoxycarbonyl)-4-hydroxypyrrolidine-2-carboxylic acid (1.0 eq.) in isopropyl acetate (5 vol) was cooled to 0° C. and TEMPO (0.05 eq.) was added. A solution of bleach (12.5 wt %, 1.2 eq., 2.6 vol) was then slowly added over 1 hour while maintaining the temperature at 0-5° C. The mixture was stirred and monitored by HPLC for completion, then aqueous 10% KHSO4 (2.5 vol) was added, stirred for 10 minutes, and then the phases were separated. The organic phase was washed with aqueous 5% Na2SO3 (2 vol) then brine (1 vol) then dried azeotropically and concentrated to afford the title compound as a solid. The solid was triturated with acetonitrile (1.0 vol) to remove residual color and impurities. 1H-NMR (400 MHz, DMSO): δ 4.54 (m, 1H), 3.82 (m, 1H), 3.67 (m, 1H); 3.15 (m, 1H); ≈2.50 (m, 1H, coincides with DMSO); 1.42 and 1.39 (2 s rotamers, 9H).

出典